Merge branch 'develop'

CHANGELOG.md

@@ -3,6 +3,16 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+## [v1.3.1] - 2021-01-04
+### Added
+- Collection: long press and move to select/deselect multiple entries
+- Info: show Spherical Video V1 metadata
+- Info: metadata search
+
+### Fixed
+- Viewer: fixed panning inertia following double-tap scaling
+- Collection: fixed crash when loading TIFF files on Android 11
+
 ## [v1.3.0] - 2020-12-26
 ### Added
 - Viewer: quick scale (aka one finger zoom)

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/DebugHandler.kt

@@ -240,26 +240,29 @@ class DebugHandler(private val context: Context) : MethodCallHandler {
 
         try {
             val metadataMap = HashMap<String, FieldMap>()
-            var dirCount: Int? = null
+            var fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd()
-            context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+            if (fd == null) {
-                val options = TiffBitmapFactory.Options().apply {
+                result.error("getTiffStructure-fd", "failed to get file descriptor", null)
-                    inJustDecodeBounds = true
+                return
-                }
-                TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
-                metadataMap["0"] = tiffOptionsToMap(options)
-                dirCount = options.outDirectoryCount
             }
-            if (dirCount != null) {
+            var options = TiffBitmapFactory.Options().apply {
-                for (i in 1 until dirCount!!) {
+                inJustDecodeBounds = true
-                    context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+            }
-                        val options = TiffBitmapFactory.Options().apply {
+            TiffBitmapFactory.decodeFileDescriptor(fd, options)
-                            inJustDecodeBounds = true
+            metadataMap["0"] = tiffOptionsToMap(options)
-                            inDirectoryNumber = i
+            val dirCount = options.outDirectoryCount
-                        }
+            for (i in 1 until dirCount) {
-                        TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+                fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd()
-                        metadataMap["$i"] = tiffOptionsToMap(options)
+                if (fd == null) {
-                    }
+                    result.error("getTiffStructure-fd", "failed to get file descriptor", null)
+                    return
                 }
+                options = TiffBitmapFactory.Options().apply {
+                    inJustDecodeBounds = true
+                    inDirectoryNumber = i
+                }
+                TiffBitmapFactory.decodeFileDescriptor(fd, options)
+                metadataMap["$i"] = tiffOptionsToMap(options)
             }
             result.success(metadataMap)
         } catch (e: Exception) {

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataHandler.kt

@@ -21,17 +21,15 @@ import com.drew.metadata.iptc.IptcDirectory
 import com.drew.metadata.mp4.media.Mp4UuidBoxDirectory
 import com.drew.metadata.webp.WebpDirectory
 import com.drew.metadata.xmp.XmpDirectory
+import deckers.thibault.aves.metadata.*
 import deckers.thibault.aves.metadata.ExifInterfaceHelper.describeAll
 import deckers.thibault.aves.metadata.ExifInterfaceHelper.getSafeDateMillis
 import deckers.thibault.aves.metadata.ExifInterfaceHelper.getSafeDouble
 import deckers.thibault.aves.metadata.ExifInterfaceHelper.getSafeInt
 import deckers.thibault.aves.metadata.ExifInterfaceHelper.getSafeRational
-import deckers.thibault.aves.metadata.Geotiff
-import deckers.thibault.aves.metadata.MediaMetadataRetrieverHelper
 import deckers.thibault.aves.metadata.MediaMetadataRetrieverHelper.getSafeDateMillis
 import deckers.thibault.aves.metadata.MediaMetadataRetrieverHelper.getSafeDescription
 import deckers.thibault.aves.metadata.MediaMetadataRetrieverHelper.getSafeInt
-import deckers.thibault.aves.metadata.Metadata
 import deckers.thibault.aves.metadata.Metadata.getRotationDegreesForExifCode
 import deckers.thibault.aves.metadata.Metadata.isFlippedForExifCode
 import deckers.thibault.aves.metadata.MetadataExtractorHelper.getSafeBoolean
@@ -40,7 +38,6 @@ import deckers.thibault.aves.metadata.MetadataExtractorHelper.getSafeInt
 import deckers.thibault.aves.metadata.MetadataExtractorHelper.getSafeRational
 import deckers.thibault.aves.metadata.MetadataExtractorHelper.getSafeString
 import deckers.thibault.aves.metadata.MetadataExtractorHelper.isGeoTiff
-import deckers.thibault.aves.metadata.XMP
 import deckers.thibault.aves.metadata.XMP.getSafeDateMillis
 import deckers.thibault.aves.metadata.XMP.getSafeLocalizedText
 import deckers.thibault.aves.metadata.XMP.isPanorama
@@ -142,6 +139,14 @@ class MetadataHandler(private val context: Context) : MethodCallHandler {
                             // remove this stat as it is not actual XMP data
                             dirMap.remove(dir.getTagName(XmpDirectory.TAG_XMP_VALUE_COUNT))
                         }
+
+                        if (dir is Mp4UuidBoxDirectory) {
+                            if (dir.getString(Mp4UuidBoxDirectory.TAG_UUID) == GSpherical.SPHERICAL_VIDEO_V1_UUID) {
+                                val bytes = dir.getByteArray(Mp4UuidBoxDirectory.TAG_USER_DATA)
+                                metadataMap["Spherical Video"] = HashMap(GSpherical(bytes).describe())
+                                metadataMap.remove(dirName)
+                            }
+                        }
                     }
                 }
             } catch (e: Exception) {
@@ -348,7 +353,7 @@ class MetadataHandler(private val context: Context) : MethodCallHandler {
 
                     // identification of spherical video (aka 360° video)
                     if (metadata.getDirectoriesOfType(Mp4UuidBoxDirectory::class.java).any {
-                            it.getString(Mp4UuidBoxDirectory.TAG_UUID) == Metadata.SPHERICAL_VIDEO_V1_UUID
+                            it.getString(Mp4UuidBoxDirectory.TAG_UUID) == GSpherical.SPHERICAL_VIDEO_V1_UUID
                         }) {
                         flags = flags or MASK_IS_360
                     }

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/TiffRegionFetcher.kt

@@ -18,20 +18,22 @@ class TiffRegionFetcher internal constructor(
         page: Int = 0,
         result: MethodChannel.Result,
     ) {
-        val resolver = context.contentResolver
         try {
-            resolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+            val fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd()
-                val options = TiffBitmapFactory.Options().apply {
+            if (fd == null) {
-                    inDirectoryNumber = page
+                result.error("getRegion-tiff-fd", "failed to get file descriptor for uri=$uri", null)
-                    inSampleSize = sampleSize
+                return
-                    inDecodeArea = DecodeArea(regionRect.left, regionRect.top, regionRect.width(), regionRect.height())
+            }
-                }
+            val options = TiffBitmapFactory.Options().apply {
-                val bitmap = TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+                inDirectoryNumber = page
-                if (bitmap != null) {
+                inSampleSize = sampleSize
-                    result.success(bitmap.getBytes(canHaveAlpha = true, recycle = true))
+                inDecodeArea = DecodeArea(regionRect.left, regionRect.top, regionRect.width(), regionRect.height())
-                } else {
+            }
-                    result.error("getRegion-tiff-null", "failed to decode region for uri=$uri page=$page regionRect=$regionRect", null)
+            val bitmap = TiffBitmapFactory.decodeFileDescriptor(fd, options)
-                }
+            if (bitmap != null) {
+                result.success(bitmap.getBytes(canHaveAlpha = true, recycle = true))
+            } else {
+                result.error("getRegion-tiff-null", "failed to decode region for uri=$uri page=$page regionRect=$regionRect", null)
             }
         } catch (e: Exception) {
             result.error("getRegion-tiff-read-exception", "failed to read from uri=$uri page=$page regionRect=$regionRect", e.message)

android/app/src/main/kotlin/deckers/thibault/aves/channel/streams/ImageByteStreamHandler.kt

@@ -139,28 +139,33 @@ class ImageByteStreamHandler(private val activity: Activity, private val argumen
     private fun streamTiffImage(uri: Uri, page: Int = 0) {
         val resolver = activity.contentResolver
         try {
-            var dirCount = 0
+            var fd = resolver.openFileDescriptor(uri, "r")?.detachFd()
-            resolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+            if (fd == null) {
-                val options = TiffBitmapFactory.Options().apply {
+                error("streamImage-tiff-fd", "failed to get file descriptor for uri=$uri", null)
-                    inJustDecodeBounds = true
+                return
-                }
-                TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
-                dirCount = options.outDirectoryCount
             }
+            var options = TiffBitmapFactory.Options().apply {
+                inJustDecodeBounds = true
+            }
+            TiffBitmapFactory.decodeFileDescriptor(fd, options)
+            val dirCount = options.outDirectoryCount
 
             // TODO TLAD handle multipage TIFF
             if (dirCount > page) {
-                resolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+                fd = resolver.openFileDescriptor(uri, "r")?.detachFd()
-                    val options = TiffBitmapFactory.Options().apply {
+                if (fd == null) {
-                        inJustDecodeBounds = false
+                    error("streamImage-tiff-fd", "failed to get file descriptor for uri=$uri", null)
-                        inDirectoryNumber = page
+                    return
-                    }
+                }
-                    val bitmap = TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+                options = TiffBitmapFactory.Options().apply {
-                    if (bitmap != null) {
+                    inJustDecodeBounds = false
-                        success(bitmap.getBytes(canHaveAlpha = true, recycle = true))
+                    inDirectoryNumber = page
-                    } else {
+                }
-                        error("streamImage-tiff-null", "failed to get tiff image (dir=$page) from uri=$uri", null)
+                val bitmap = TiffBitmapFactory.decodeFileDescriptor(fd, options)
-                    }
+                if (bitmap != null) {
+                    success(bitmap.getBytes(canHaveAlpha = true, recycle = true))
+                } else {
+                    error("streamImage-tiff-null", "failed to get tiff image (dir=$page) from uri=$uri", null)
                 }
             }
         } catch (e: Exception) {

android/app/src/main/kotlin/deckers/thibault/aves/decoder/TiffThumbnailGlideModule.kt

@@ -48,30 +48,35 @@ internal class TiffThumbnailFetcher(val model: TiffThumbnail, val width: Int, va
         val uri = model.uri
 
         // determine sample size
+        var fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd()
+        if (fd == null) {
+            callback.onLoadFailed(Exception("null file descriptor"))
+            return
+        }
         var sampleSize = 1
-        context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+        var options = TiffBitmapFactory.Options().apply {
-            val options = TiffBitmapFactory.Options().apply {
+            inJustDecodeBounds = true
-                inJustDecodeBounds = true
+        }
-            }
+        TiffBitmapFactory.decodeFileDescriptor(fd, options)
-            TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+        val imageWidth = options.outWidth
-            val imageWidth = options.outWidth
+        val imageHeight = options.outHeight
-            val imageHeight = options.outHeight
+        if (imageHeight > height || imageWidth > width) {
-            if (imageHeight > height || imageWidth > width) {
+            while (imageHeight / (sampleSize * 2) > height && imageWidth / (sampleSize * 2) > width) {
-                while (imageHeight / (sampleSize * 2) > height && imageWidth / (sampleSize * 2) > width) {
+                sampleSize *= 2
-                    sampleSize *= 2
-                }
             }
         }
 
         // decode
-        val bitmap = context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+        fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd()
-            val options = TiffBitmapFactory.Options().apply {
+        if (fd == null) {
-                inJustDecodeBounds = false
+            callback.onLoadFailed(Exception("null file descriptor"))
-                inSampleSize = sampleSize
+            return
-            }
-            TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
         }
-
+        options = TiffBitmapFactory.Options().apply {
+            inJustDecodeBounds = false
+            inSampleSize = sampleSize
+        }
+        val bitmap = TiffBitmapFactory.decodeFileDescriptor(fd, options)
         if (bitmap == null) {
             callback.onLoadFailed(Exception("null bitmap"))
         } else {

android/app/src/main/kotlin/deckers/thibault/aves/metadata/Metadata.kt

@@ -19,9 +19,6 @@ object Metadata {
     // "+51.3328-000.7053+113.474/" (Apple)
     val VIDEO_LOCATION_PATTERN: Pattern = Pattern.compile("([+-][.0-9]+)([+-][.0-9]+).*")
 
-    // cf https://github.com/google/spatial-media
-    const val SPHERICAL_VIDEO_V1_UUID = "ffcc8263-f855-4a93-8814-587a02521fdd"
-
     // directory names, as shown when listing all metadata
     const val DIR_GPS = "GPS" // from metadata-extractor
     const val DIR_XMP = "XMP" // from metadata-extractor

android/app/src/main/kotlin/deckers/thibault/aves/metadata/SphericalVideo.kt

@@ -0,0 +1,109 @@
+package deckers.thibault.aves.metadata
+
+import android.util.Log
+import android.util.Xml
+import deckers.thibault.aves.utils.LogUtils
+import org.xmlpull.v1.XmlPullParser
+import java.io.ByteArrayInputStream
+
+// `xmlBytes`: bytes representing the XML embedded in a MP4 `uuid` box, according to Spherical Video V1 spec
+class GSpherical(xmlBytes: ByteArray) {
+    var spherical: Boolean = false
+    var stitched: Boolean = false
+    var stitchingSoftware: String = ""
+    var projectionType: String = ""
+    var stereoMode: String? = null
+    var sourceCount: Int? = null
+    var initialViewHeadingDegrees: Int? = null
+    var initialViewPitchDegrees: Int? = null
+    var initialViewRollDegrees: Int? = null
+    var timestamp: Int? = null
+    var fullPanoWidthPixels: Int? = null
+    var fullPanoHeightPixels: Int? = null
+    var croppedAreaImageWidthPixels: Int? = null
+    var croppedAreaImageHeightPixels: Int? = null
+    var croppedAreaLeftPixels: Int? = null
+    var croppedAreaTopPixels: Int? = null
+
+    init {
+        try {
+            ByteArrayInputStream(xmlBytes).use {
+                val parser = Xml.newPullParser().apply {
+                    setInput(it, null)
+                    nextTag()
+                    require(XmlPullParser.START_TAG, RDF_NS, "SphericalVideo")
+                }
+                while (parser.next() != XmlPullParser.END_TAG) {
+                    if (parser.eventType != XmlPullParser.START_TAG) continue
+                    if (parser.namespace == GSPHERICAL_NS) {
+                        when (val tag = parser.name) {
+                            "Spherical" -> spherical = readTag(parser, tag) == "true"
+                            "Stitched" -> stitched = readTag(parser, tag) == "true"
+                            "StitchingSoftware" -> stitchingSoftware = readTag(parser, tag)
+                            "ProjectionType" -> projectionType = readTag(parser, tag)
+                            "StereoMode" -> stereoMode = readTag(parser, tag)
+                            "SourceCount" -> sourceCount = Integer.parseInt(readTag(parser, tag))
+                            "InitialViewHeadingDegrees" -> initialViewHeadingDegrees = Integer.parseInt(readTag(parser, tag))
+                            "InitialViewPitchDegrees" -> initialViewPitchDegrees = Integer.parseInt(readTag(parser, tag))
+                            "InitialViewRollDegrees" -> initialViewRollDegrees = Integer.parseInt(readTag(parser, tag))
+                            "Timestamp" -> timestamp = Integer.parseInt(readTag(parser, tag))
+                            "FullPanoWidthPixels" -> fullPanoWidthPixels = Integer.parseInt(readTag(parser, tag))
+                            "FullPanoHeightPixels" -> fullPanoHeightPixels = Integer.parseInt(readTag(parser, tag))
+                            "CroppedAreaImageWidthPixels" -> croppedAreaImageWidthPixels = Integer.parseInt(readTag(parser, tag))
+                            "CroppedAreaImageHeightPixels" -> croppedAreaImageHeightPixels = Integer.parseInt(readTag(parser, tag))
+                            "CroppedAreaLeftPixels" -> croppedAreaLeftPixels = Integer.parseInt(readTag(parser, tag))
+                            "CroppedAreaTopPixels" -> croppedAreaTopPixels = Integer.parseInt(readTag(parser, tag))
+                        }
+                    }
+                }
+            }
+        } catch (e: Exception) {
+            Log.w(LOG_TAG, "failed to parse XML", e)
+        }
+    }
+
+    fun describe(): Map<String, String?> = hashMapOf(
+        "Spherical" to spherical.toString(),
+        "Stitched" to stitched.toString(),
+        "Stitching Software" to stitchingSoftware,
+        "Projection Type" to projectionType,
+        "Stereo Mode" to stereoMode,
+        "Source Count" to sourceCount?.toString(),
+        "Initial View Heading Degrees" to initialViewHeadingDegrees?.toString(),
+        "Initial View Pitch Degrees" to initialViewPitchDegrees?.toString(),
+        "Initial View Roll Degrees" to initialViewRollDegrees?.toString(),
+        "Timestamp" to timestamp?.toString(),
+        "Full Panorama Width Pixels" to fullPanoWidthPixels?.toString(),
+        "Full Panorama Height Pixels" to fullPanoHeightPixels?.toString(),
+        "Cropped Area Image Width Pixels" to croppedAreaImageWidthPixels?.toString(),
+        "Cropped Area Image Height Pixels" to croppedAreaImageHeightPixels?.toString(),
+        "Cropped Area Left Pixels" to croppedAreaLeftPixels?.toString(),
+        "Cropped Area Top Pixels" to croppedAreaTopPixels?.toString(),
+    ).filterValues { it != null }
+
+    companion object SphericalVideo {
+        private val LOG_TAG = LogUtils.createTag(SphericalVideo::class.java)
+
+        // cf https://github.com/google/spatial-media
+        const val SPHERICAL_VIDEO_V1_UUID = "ffcc8263-f855-4a93-8814-587a02521fdd"
+
+        const val RDF_NS = "http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+        const val GSPHERICAL_NS = "http://ns.google.com/videos/1.0/spherical/"
+
+        private fun readText(parser: XmlPullParser): String {
+            var text = ""
+            if (parser.next() == XmlPullParser.TEXT) {
+                text = parser.text
+                parser.nextTag()
+            }
+            return text
+        }
+
+        private fun readTag(parser: XmlPullParser, tag: String): String {
+            parser.require(XmlPullParser.START_TAG, GSPHERICAL_NS, tag)
+            val text = readText(parser)
+            parser.require(XmlPullParser.END_TAG, GSPHERICAL_NS, tag)
+            return text
+        }
+    }
+}

android/app/src/main/kotlin/deckers/thibault/aves/model/SourceImageEntry.kt

@@ -249,14 +249,13 @@ class SourceImageEntry {
 
     private fun fillByTiffDecode(context: Context) {
         try {
-            context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+            val fd = context.contentResolver.openFileDescriptor(uri, "r")?.detachFd() ?: return
-                val options = TiffBitmapFactory.Options().apply {
+            val options = TiffBitmapFactory.Options().apply {
-                    inJustDecodeBounds = true
+                inJustDecodeBounds = true
-                }
-                TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
-                width = options.outWidth
-                height = options.outHeight
             }
+            TiffBitmapFactory.decodeFileDescriptor(fd, options)
+            width = options.outWidth
+            height = options.outHeight
         } catch (e: Exception) {
             // ignore
         }

lib/widgets/collection/app_bar.dart

@@ -172,7 +172,7 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
   List<Widget> _buildActions() {
     return [
       if (collection.isBrowsing)
-        SearchButton(
+        CollectionSearchButton(
           source,
           parentCollection: collection,
         ),
@@ -361,7 +361,7 @@ class _CollectionAppBarState extends State<CollectionAppBar> with SingleTickerPr
     Navigator.push(
         context,
         SearchPageRoute(
-          delegate: ImageSearchDelegate(
+          delegate: CollectionSearchDelegate(
             source: collection.source,
             parentCollection: collection,
           ),

lib/widgets/collection/grid/list_section_layout.dart

@@ -3,6 +3,7 @@ import 'dart:math';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/widgets/collection/grid/header_generic.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
@@ -143,6 +144,25 @@ class SectionedListLayout {
     final top = sectionLayout.indexToLayoutOffset(listIndex);
     return Rect.fromLTWH(left, top, tileExtent, tileExtent);
   }
+
+  ImageEntry getEntryAt(Offset position) {
+    var dy = position.dy;
+    final sectionLayout = sectionLayouts.firstWhere((sl) => dy < sl.maxOffset, orElse: () => null);
+    if (sectionLayout == null) return null;
+
+    final section = collection.sections[sectionLayout.sectionKey];
+    if (section == null) return null;
+
+    dy -= sectionLayout.minOffset + sectionLayout.headerExtent;
+    if (dy < 0) return null;
+
+    final row = dy ~/ tileExtent;
+    final column = position.dx ~/ tileExtent;
+    final index = row * columnCount + column;
+    if (index >= section.length) return null;
+
+    return section[index];
+  }
 }
 
 class SectionLayout {
@@ -184,4 +204,7 @@ class SectionLayout {
     scrollOffset -= minOffset + headerExtent;
     return firstIndex + (scrollOffset < 0 ? 0 : (scrollOffset / tileExtent).ceil() - 1);
   }
+
+  @override
+  String toString() => '$runtimeType#${shortHash(this)}{sectionKey=$sectionKey, firstIndex=$firstIndex, lastIndex=$lastIndex, minOffset=$minOffset, maxOffset=$maxOffset, headerExtent=$headerExtent}';
 }

lib/widgets/collection/grid/list_sliver.dart

@@ -65,11 +65,6 @@ class GridThumbnail extends StatelessWidget {
           ViewerService.pick(entry.uri);
         }
       },
-      onLongPress: () {
-        if (AvesApp.mode == AppMode.main) {
-          collection.toggleSelection(entry);
-        }
-      },
       child: MetaData(
         metaData: ScalerMetadata(entry),
         child: DecoratedThumbnail(

lib/widgets/collection/grid/selector.dart

@@ -0,0 +1,169 @@
+import 'dart:async';
+import 'dart:math';
+
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/model/source/collection_lens.dart';
+import 'package:aves/utils/math_utils.dart';
+import 'package:aves/widgets/collection/grid/list_section_layout.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
+import 'package:provider/provider.dart';
+
+class GridSelectionGestureDetector extends StatefulWidget {
+  final bool selectable;
+  final CollectionLens collection;
+  final ScrollController scrollController;
+  final ValueNotifier<double> appBarHeightNotifier;
+  final Widget child;
+
+  const GridSelectionGestureDetector({
+    this.selectable = true,
+    @required this.collection,
+    @required this.scrollController,
+    @required this.appBarHeightNotifier,
+    @required this.child,
+  });
+
+  @override
+  _GridSelectionGestureDetectorState createState() => _GridSelectionGestureDetectorState();
+}
+
+class _GridSelectionGestureDetectorState extends State<GridSelectionGestureDetector> {
+  bool _pressing, _selecting;
+  int _fromIndex, _lastToIndex;
+  Offset _localPosition;
+  EdgeInsets _scrollableInsets;
+  double _scrollSpeedFactor;
+  Timer _updateTimer;
+
+  CollectionLens get collection => widget.collection;
+
+  List<ImageEntry> get entries => collection.sortedEntries;
+
+  ScrollController get scrollController => widget.scrollController;
+
+  double get appBarHeight => widget.appBarHeightNotifier.value;
+
+  static const double scrollEdgeRatio = .15;
+  static const double scrollMaxPixelPerSecond = 600.0;
+  static const Duration scrollUpdateInterval = Duration(milliseconds: 100);
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onLongPressStart: widget.selectable
+          ? (details) {
+              final fromEntry = _getEntryAt(details.localPosition);
+              if (fromEntry == null) return;
+
+              collection.toggleSelection(fromEntry);
+              _selecting = collection.isSelected([fromEntry]);
+              _fromIndex = entries.indexOf(fromEntry);
+              _lastToIndex = _fromIndex;
+              _scrollableInsets = EdgeInsets.only(
+                top: appBarHeight,
+                bottom: context.read<MediaQueryData>().viewInsets.bottom,
+              );
+              _scrollSpeedFactor = 0;
+              _pressing = true;
+            }
+          : null,
+      onLongPressMoveUpdate: widget.selectable
+          ? (details) {
+              if (!_pressing) return;
+              _localPosition = details.localPosition;
+              _onLongPressUpdate();
+            }
+          : null,
+      onLongPressEnd: widget.selectable
+          ? (details) {
+              if (!_pressing) return;
+              _setScrollSpeed(0);
+              _pressing = false;
+            }
+          : null,
+      child: widget.child,
+    );
+  }
+
+  void _onLongPressUpdate() {
+    final dy = _localPosition.dy;
+
+    final height = scrollController.position.viewportDimension;
+    final top = dy < height / 2;
+
+    final distanceToEdge = max(0, top ? dy - _scrollableInsets.top : height - dy - _scrollableInsets.bottom);
+    final threshold = height * scrollEdgeRatio;
+    if (distanceToEdge < threshold) {
+      _setScrollSpeed((top ? -1 : 1) * roundToPrecision((threshold - distanceToEdge) / threshold, decimals: 1));
+    } else {
+      _setScrollSpeed(0);
+    }
+
+    final toEntry = _getEntryAt(_localPosition);
+    _toggleSelectionToIndex(entries.indexOf(toEntry));
+  }
+
+  void _setScrollSpeed(double speedFactor) {
+    if (speedFactor == _scrollSpeedFactor) return;
+    _scrollSpeedFactor = speedFactor;
+    _updateTimer?.cancel();
+
+    final current = scrollController.offset;
+    if (speedFactor == 0) {
+      scrollController.jumpTo(current);
+      return;
+    }
+
+    final target = speedFactor > 0 ? scrollController.position.maxScrollExtent : .0;
+    if (target != current) {
+      final distance = target - current;
+      final millis = distance * 1000 / scrollMaxPixelPerSecond / speedFactor;
+      scrollController.animateTo(
+        target,
+        duration: Duration(milliseconds: millis.round()),
+        curve: Curves.linear,
+      );
+      // use a timer to update the entry selection, because `onLongPressMoveUpdate`
+      // is not called when the pointer stays still while the view is scrolling
+      _updateTimer = Timer.periodic(scrollUpdateInterval, (_) => _onLongPressUpdate());
+    }
+  }
+
+  ImageEntry _getEntryAt(Offset localPosition) {
+    // as of Flutter v1.22.5, `hitTest` on the `ScrollView` render object works fine when it is static,
+    // but when it is scrolling (through controller animation), result is incomplete and children are missing,
+    // so we use custom layout computation instead to find the entry.
+    final offset = Offset(0, scrollController.offset - appBarHeight) + localPosition;
+    return context.read<SectionedListLayout>().getEntryAt(offset);
+  }
+
+  void _toggleSelectionToIndex(int toIndex) {
+    if (toIndex == -1) return;
+
+    if (_selecting) {
+      if (toIndex <= _fromIndex) {
+        if (toIndex < _lastToIndex) {
+          collection.addToSelection(entries.getRange(toIndex, min(_fromIndex, _lastToIndex)));
+          if (_fromIndex < _lastToIndex) {
+            collection.removeFromSelection(entries.getRange(_fromIndex + 1, _lastToIndex + 1));
+          }
+        } else if (_lastToIndex < toIndex) {
+          collection.removeFromSelection(entries.getRange(_lastToIndex, toIndex));
+        }
+      } else if (_fromIndex < toIndex) {
+        if (_lastToIndex < toIndex) {
+          collection.addToSelection(entries.getRange(max(_fromIndex, _lastToIndex), toIndex + 1));
+          if (_lastToIndex < _fromIndex) {
+            collection.removeFromSelection(entries.getRange(_lastToIndex, _fromIndex));
+          }
+        } else if (toIndex < _lastToIndex) {
+          collection.removeFromSelection(entries.getRange(toIndex + 1, _lastToIndex + 1));
+        }
+      }
+      _lastToIndex = toIndex;
+    } else {
+      collection.removeFromSelection(entries.getRange(min(_fromIndex, toIndex), max(_fromIndex, toIndex) + 1));
+    }
+  }
+}

lib/widgets/collection/thumbnail_collection.dart

@@ -1,5 +1,6 @@
 import 'dart:async';
 
+import 'package:aves/main.dart';
 import 'package:aves/model/filters/favourite.dart';
 import 'package:aves/model/filters/mime.dart';
 import 'package:aves/model/highlight.dart';
@@ -13,6 +14,7 @@ import 'package:aves/widgets/collection/app_bar.dart';
 import 'package:aves/widgets/collection/empty.dart';
 import 'package:aves/widgets/collection/grid/list_section_layout.dart';
 import 'package:aves/widgets/collection/grid/list_sliver.dart';
+import 'package:aves/widgets/collection/grid/selector.dart';
 import 'package:aves/widgets/collection/thumbnail/decorated.dart';
 import 'package:aves/widgets/common/behaviour/routes.dart';
 import 'package:aves/widgets/common/behaviour/sloppy_scroll_physics.dart';
@@ -53,6 +55,7 @@ class ThumbnailCollection extends StatelessWidget {
               spacing: spacing,
             )..applyTileExtent(viewportSize: viewportSize);
             final cacheExtent = tileExtentManager.getEffectiveExtentMax(viewportSize) * 2;
+            final scrollController = PrimaryScrollController.of(context);
 
             // do not replace by Provider.of<CollectionLens>
             // so that view updates on collection filter changes
@@ -67,7 +70,7 @@ class ThumbnailCollection extends StatelessWidget {
                   ),
                   appBarHeightNotifier: _appBarHeightNotifier,
                   isScrollingNotifier: _isScrollingNotifier,
-                  scrollController: PrimaryScrollController.of(context),
+                  scrollController: scrollController,
                   cacheExtent: cacheExtent,
                 );
 
@@ -102,6 +105,14 @@ class ThumbnailCollection extends StatelessWidget {
                   child: scrollView,
                 );
 
+                final selector = GridSelectionGestureDetector(
+                  selectable: AvesApp.mode == AppMode.main,
+                  collection: collection,
+                  scrollController: scrollController,
+                  appBarHeightNotifier: _appBarHeightNotifier,
+                  child: scaler,
+                );
+
                 final sectionedListLayoutProvider = ValueListenableBuilder<double>(
                   valueListenable: _tileExtentNotifier,
                   builder: (context, tileExtent, child) => SectionedListLayoutProvider(
@@ -116,7 +127,7 @@ class ThumbnailCollection extends StatelessWidget {
                       tileExtent: tileExtent,
                       isScrollingNotifier: _isScrollingNotifier,
                     ),
-                    child: scaler,
+                    child: selector,
                   ),
                 );
                 return sectionedListLayoutProvider;

lib/widgets/common/basic/query_bar.dart

@@ -0,0 +1,79 @@
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/utils/debouncer.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+class QueryBar extends StatefulWidget {
+  final ValueNotifier<String> filterNotifier;
+
+  const QueryBar({@required this.filterNotifier});
+
+  @override
+  _QueryBarState createState() => _QueryBarState();
+}
+
+class _QueryBarState extends State<QueryBar> {
+  final Debouncer _debouncer = Debouncer(delay: Durations.searchDebounceDelay);
+  TextEditingController _controller;
+
+  ValueNotifier<String> get filterNotifier => widget.filterNotifier;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller = TextEditingController(text: filterNotifier.value);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final clearButton = IconButton(
+      icon: Icon(AIcons.clear),
+      onPressed: () {
+        _controller.clear();
+        filterNotifier.value = '';
+      },
+      tooltip: 'Clear',
+    );
+
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Expanded(
+          child: TextField(
+            controller: _controller,
+            decoration: InputDecoration(
+              icon: Padding(
+                padding: EdgeInsetsDirectional.only(start: 16),
+                child: Icon(AIcons.search),
+              ),
+              hintText: MaterialLocalizations.of(context).searchFieldLabel,
+              hintStyle: Theme.of(context).inputDecorationTheme.hintStyle,
+            ),
+            textInputAction: TextInputAction.search,
+            onChanged: (s) => _debouncer(() => filterNotifier.value = s),
+          ),
+        ),
+        ConstrainedBox(
+          constraints: BoxConstraints(minWidth: 16),
+          child: ValueListenableBuilder<TextEditingValue>(
+            valueListenable: _controller,
+            builder: (context, value, child) => AnimatedSwitcher(
+              duration: Durations.appBarActionChangeAnimation,
+              transitionBuilder: (child, animation) => FadeTransition(
+                opacity: animation,
+                child: SizeTransition(
+                  axis: Axis.horizontal,
+                  sizeFactor: animation,
+                  child: child,
+                ),
+              ),
+              child: value.text.isNotEmpty ? clearButton : SizedBox.shrink(),
+            ),
+          ),
+        )
+      ],
+    );
+  }
+}

lib/widgets/common/identity/aves_expansion_tile.dart

@@ -5,13 +5,15 @@ import 'package:flutter/material.dart';
 class AvesExpansionTile extends StatelessWidget {
   final String title;
   final Color color;
-  final List<Widget> children;
   final ValueNotifier<String> expandedNotifier;
+  final bool initiallyExpanded;
+  final List<Widget> children;
 
   const AvesExpansionTile({
     @required this.title,
     this.color,
     this.expandedNotifier,
+    this.initiallyExpanded = false,
     @required this.children,
   });
 
@@ -33,6 +35,9 @@ class AvesExpansionTile extends StatelessWidget {
           enabled: enabled,
         ),
         expandable: enabled,
+        initiallyExpanded: initiallyExpanded,
+        baseColor: Colors.grey[900],
+        expandedColor: Colors.grey[850],
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
@@ -41,8 +46,6 @@ class AvesExpansionTile extends StatelessWidget {
             if (enabled) ...children,
           ],
         ),
-        baseColor: Colors.grey[900],
-        expandedColor: Colors.grey[850],
       ),
     );
   }

lib/widgets/common/identity/aves_filter_chip.dart

@@ -168,6 +168,8 @@ class _AvesFilterChipState extends State<AvesFilterChip> {
                 borderRadius: borderRadius,
               ),
               child: InkWell(
+                // as of Flutter v1.22.5, `InkWell` does not have `onLongPressStart` like `GestureDetector`,
+                // so we get the long press details from the tap instead
                 onTapDown: (details) => _tapPosition = details.globalPosition,
                 onTap: widget.onTap != null
                     ? () {

lib/widgets/common/magnifier/core/core.dart

@@ -43,7 +43,7 @@ class MagnifierCoreState extends State<MagnifierCore> with TickerProviderStateMi
   Offset _startFocalPoint, _lastViewportFocalPosition;
   double _startScale, _quickScaleLastY, _quickScaleLastDistance;
   bool _doubleTap, _quickScaleMoved;
-  DateTime _lastScaleGestureDate;
+  DateTime _lastScaleGestureDate = DateTime.now();
 
   AnimationController _scaleAnimationController;
   Animation<double> _scaleAnimation;

lib/widgets/filter_grids/album_pick.dart

@@ -3,10 +3,9 @@ import 'package:aves/model/filters/album.dart';
 import 'package:aves/model/settings/settings.dart';
 import 'package:aves/model/source/collection_source.dart';
 import 'package:aves/model/source/enums.dart';
-import 'package:aves/theme/durations.dart';
 import 'package:aves/theme/icons.dart';
-import 'package:aves/utils/debouncer.dart';
 import 'package:aves/widgets/collection/empty.dart';
+import 'package:aves/widgets/common/basic/query_bar.dart';
 import 'package:aves/widgets/dialogs/create_album_dialog.dart';
 import 'package:aves/widgets/filter_grids/albums_page.dart';
 import 'package:aves/widgets/filter_grids/common/chip_set_action_delegate.dart';
@@ -116,84 +115,25 @@ class AlbumPickAppBar extends StatelessWidget {
   }
 }
 
-class AlbumFilterBar extends StatefulWidget implements PreferredSizeWidget {
+class AlbumFilterBar extends StatelessWidget implements PreferredSizeWidget {
   final ValueNotifier<String> filterNotifier;
 
   static const preferredHeight = kToolbarHeight;
 
-  const AlbumFilterBar({@required this.filterNotifier});
+  const AlbumFilterBar({
+    @required this.filterNotifier,
+  });
 
   @override
   Size get preferredSize => Size.fromHeight(preferredHeight);
 
-  @override
-  _AlbumFilterBarState createState() => _AlbumFilterBarState();
-}
-
-class _AlbumFilterBarState extends State<AlbumFilterBar> {
-  final Debouncer _debouncer = Debouncer(delay: Durations.searchDebounceDelay);
-  TextEditingController _controller;
-
-  ValueNotifier<String> get filterNotifier => widget.filterNotifier;
-
-  @override
-  void initState() {
-    super.initState();
-    _controller = TextEditingController(text: filterNotifier.value);
-  }
-
   @override
   Widget build(BuildContext context) {
-    final clearButton = IconButton(
-      icon: Icon(AIcons.clear),
-      onPressed: () {
-        _controller.clear();
-        filterNotifier.value = '';
-      },
-      tooltip: 'Clear',
-    );
     return Container(
       height: AlbumFilterBar.preferredHeight,
       alignment: Alignment.topCenter,
-      child: Row(
+      child: QueryBar(
-        crossAxisAlignment: CrossAxisAlignment.start,
+        filterNotifier: filterNotifier,
-        children: [
-          // Icon(AIcons.search),
-          Expanded(
-            child: TextField(
-              controller: _controller,
-              decoration: InputDecoration(
-                icon: Padding(
-                  padding: EdgeInsetsDirectional.only(start: 16),
-                  child: Icon(AIcons.search),
-                ),
-                // border: OutlineInputBorder(),
-                hintText: MaterialLocalizations.of(context).searchFieldLabel,
-                hintStyle: Theme.of(context).inputDecorationTheme.hintStyle,
-              ),
-              textInputAction: TextInputAction.search,
-              onChanged: (s) => _debouncer(() => filterNotifier.value = s),
-            ),
-          ),
-          ConstrainedBox(
-            constraints: BoxConstraints(minWidth: 16),
-            child: ValueListenableBuilder<TextEditingValue>(
-              valueListenable: _controller,
-              builder: (context, value, child) => AnimatedSwitcher(
-                duration: Durations.appBarActionChangeAnimation,
-                transitionBuilder: (child, animation) => FadeTransition(
-                  opacity: animation,
-                  child: SizeTransition(
-                    axis: Axis.horizontal,
-                    sizeFactor: animation,
-                    child: child,
-                  ),
-                ),
-                child: value.text.isNotEmpty ? clearButton : SizedBox.shrink(),
-              ),
-            ),
-          )
-        ],
       ),
     );
   }

lib/widgets/filter_grids/common/filter_nav_page.dart

@@ -85,6 +85,7 @@ class FilterNavigationPage<T extends CollectionFilter> extends StatelessWidget {
   Future<void> _showMenu(BuildContext context, T filter, Offset tapPosition) async {
     final RenderBox overlay = Overlay.of(context).context.findRenderObject();
     final touchArea = Size(40, 40);
+    // TODO TLAD show menu within safe area
     final selectedAction = await showMenu<ChipAction>(
       context: context,
       position: RelativeRect.fromRect(tapPosition & touchArea, Offset.zero & overlay.size),
@@ -103,7 +104,7 @@ class FilterNavigationPage<T extends CollectionFilter> extends StatelessWidget {
 
   List<Widget> _buildActions(BuildContext context) {
     return [
-      SearchButton(source),
+      CollectionSearchButton(source),
       PopupMenuButton<ChipSetAction>(
         key: Key('appbar-menu-button'),
         itemBuilder: (context) {
@@ -136,7 +137,7 @@ class FilterNavigationPage<T extends CollectionFilter> extends StatelessWidget {
     Navigator.push(
         context,
         SearchPageRoute(
-          delegate: ImageSearchDelegate(
+          delegate: CollectionSearchDelegate(
             source: source,
           ),
         ));

lib/widgets/fullscreen/info/info_app_bar.dart

@@ -0,0 +1,53 @@
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/widgets/common/app_bar_title.dart';
+import 'package:aves/widgets/fullscreen/info/info_search.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_section.dart';
+import 'package:flutter/material.dart';
+
+class InfoAppBar extends StatelessWidget {
+  final ImageEntry entry;
+  final ValueNotifier<Map<String, MetadataDirectory>> metadataNotifier;
+  final VoidCallback onBackPressed;
+
+  const InfoAppBar({
+    @required this.entry,
+    @required this.metadataNotifier,
+    @required this.onBackPressed,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return SliverAppBar(
+      leading: IconButton(
+        key: Key('back-button'),
+        icon: Icon(AIcons.goUp),
+        onPressed: onBackPressed,
+        tooltip: 'Back to viewer',
+      ),
+      title: TappableAppBarTitle(
+        onTap: () => _goToSearch(context),
+        child: Text('Info'),
+      ),
+      actions: [
+        IconButton(
+          icon: Icon(AIcons.search),
+          onPressed: () => _goToSearch(context),
+          tooltip: 'Search',
+        ),
+      ],
+      titleSpacing: 0,
+      floating: true,
+    );
+  }
+
+  void _goToSearch(BuildContext context) {
+    showSearch(
+      context: context,
+      delegate: InfoSearchDelegate(
+        entry: entry,
+        metadataNotifier: metadataNotifier,
+      ),
+    );
+  }
+}

lib/widgets/fullscreen/info/info_page.dart

@@ -2,9 +2,9 @@ import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/model/source/collection_lens.dart';
 import 'package:aves/theme/durations.dart';
-import 'package:aves/theme/icons.dart';
 import 'package:aves/widgets/common/providers/media_query_data_provider.dart';
 import 'package:aves/widgets/fullscreen/info/basic_section.dart';
+import 'package:aves/widgets/fullscreen/info/info_app_bar.dart';
 import 'package:aves/widgets/fullscreen/info/location_section.dart';
 import 'package:aves/widgets/fullscreen/info/metadata/metadata_section.dart';
 import 'package:aves/widgets/fullscreen/info/notifications.dart';
@@ -38,17 +38,6 @@ class InfoPageState extends State<InfoPage> {
 
   @override
   Widget build(BuildContext context) {
-    final appBar = SliverAppBar(
-      leading: IconButton(
-        key: Key('back-button'),
-        icon: Icon(AIcons.goUp),
-        onPressed: _goToImage,
-        tooltip: 'Back to viewer',
-      ),
-      title: Text('Info'),
-      floating: true,
-    );
-
     return MediaQueryDataProvider(
       child: Scaffold(
         body: SafeArea(
@@ -68,9 +57,9 @@ class InfoPageState extends State<InfoPage> {
                             entry: entry,
                             visibleNotifier: widget.visibleNotifier,
                             scrollController: _scrollController,
-                            appBar: appBar,
                             split: mqWidth > 400,
                             mqViewInsetsBottom: mqViewInsetsBottom,
+                            goToViewer: _goToViewer,
                           )
                         : SizedBox.shrink();
                   },
@@ -97,7 +86,7 @@ class InfoPageState extends State<InfoPage> {
           _scrollStartFromTop = false;
         } else if (notification is OverscrollNotification) {
           if (notification.overscroll < 0) {
-            _goToImage();
+            _goToViewer();
             _scrollStartFromTop = false;
           }
         }
@@ -106,7 +95,7 @@ class InfoPageState extends State<InfoPage> {
     return false;
   }
 
-  void _goToImage() {
+  void _goToViewer() {
     BackUpNotification().dispatch(context);
     _scrollController.animateTo(
       0,
@@ -121,9 +110,9 @@ class _InfoPageContent extends StatefulWidget {
   final ImageEntry entry;
   final ValueNotifier<bool> visibleNotifier;
   final ScrollController scrollController;
-  final SliverAppBar appBar;
   final bool split;
   final double mqViewInsetsBottom;
+  final VoidCallback goToViewer;
 
   const _InfoPageContent({
     Key key,
@@ -131,9 +120,9 @@ class _InfoPageContent extends StatefulWidget {
     @required this.entry,
     @required this.visibleNotifier,
     @required this.scrollController,
-    @required this.appBar,
     @required this.split,
     @required this.mqViewInsetsBottom,
+    @required this.goToViewer,
   }) : super(key: key);
 
   @override
@@ -143,6 +132,8 @@ class _InfoPageContent extends StatefulWidget {
 class _InfoPageContentState extends State<_InfoPageContent> {
   static const horizontalPadding = EdgeInsets.symmetric(horizontal: 8);
 
+  final ValueNotifier<Map<String, MetadataDirectory>> _metadataNotifier = ValueNotifier({});
+
   CollectionLens get collection => widget.collection;
 
   ImageEntry get entry => widget.entry;
@@ -178,13 +169,18 @@ class _InfoPageContentState extends State<_InfoPageContent> {
           );
     final metadataSliver = MetadataSectionSliver(
       entry: entry,
+      metadataNotifier: _metadataNotifier,
       visibleNotifier: widget.visibleNotifier,
     );
 
     return CustomScrollView(
       controller: widget.scrollController,
       slivers: [
-        widget.appBar,
+        InfoAppBar(
+          entry: entry,
+          metadataNotifier: _metadataNotifier,
+          onBackPressed: widget.goToViewer,
+        ),
         SliverPadding(
           padding: horizontalPadding + EdgeInsets.only(top: 8),
           sliver: basicAndLocationSliver,

lib/widgets/fullscreen/info/info_search.dart

@@ -0,0 +1,118 @@
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/widgets/collection/empty.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_dir_tile.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_section.dart';
+import 'package:collection/collection.dart';
+import 'package:flutter/material.dart';
+
+class InfoSearchDelegate extends SearchDelegate {
+  final ImageEntry entry;
+  final ValueNotifier<Map<String, MetadataDirectory>> metadataNotifier;
+
+  Map<String, MetadataDirectory> get metadata => metadataNotifier.value;
+
+  static const suggestions = {
+    'Date & time': 'date or time or when -timer -uptime -exposure -timeline',
+    'Description': 'abstract or description or comment',
+    'Dimensions': 'width or height or dimension or framesize or imagelength',
+    'Resolution': 'resolution',
+    'Rights': 'rights or copyright or artist or creator or by-line or credit -tool',
+  };
+
+  InfoSearchDelegate({
+    @required this.entry,
+    @required this.metadataNotifier,
+  }) : super(
+          searchFieldLabel: 'Search metadata',
+        );
+
+  @override
+  ThemeData appBarTheme(BuildContext context) {
+    return Theme.of(context);
+  }
+
+  @override
+  Widget buildLeading(BuildContext context) {
+    return IconButton(
+      icon: AnimatedIcon(
+        icon: AnimatedIcons.menu_arrow,
+        progress: transitionAnimation,
+      ),
+      onPressed: () => Navigator.pop(context),
+      tooltip: MaterialLocalizations.of(context).backButtonTooltip,
+    );
+  }
+
+  @override
+  List<Widget> buildActions(BuildContext context) {
+    return [
+      if (query.isNotEmpty)
+        IconButton(
+          icon: Icon(AIcons.clear),
+          onPressed: () {
+            query = '';
+            showSuggestions(context);
+          },
+          tooltip: 'Clear',
+        ),
+    ];
+  }
+
+  @override
+  Widget buildSuggestions(BuildContext context) => ListView(
+        children: suggestions.entries
+            .map((kv) => ListTile(
+                  title: Text(kv.key),
+                  onTap: () {
+                    query = kv.value;
+                    showResults(context);
+                  },
+                ))
+            .toList(),
+      );
+
+  @override
+  Widget buildResults(BuildContext context) {
+    if (query.isEmpty) {
+      showSuggestions(context);
+      return SizedBox();
+    }
+
+    final queryParts = query.toUpperCase().split(' ')..removeWhere((s) => s.isEmpty);
+    final queryExcludeIncludeGroups = groupBy<String, bool>(queryParts, (s) => s.startsWith('-'));
+    final queryExcludeAll = (queryExcludeIncludeGroups[true] ?? []).map((s) => s.substring(1));
+    final queryIncludeAny = (queryExcludeIncludeGroups[false] ?? []).join(' ').split(' OR ');
+
+    bool testKey(String key) {
+      key = key.toUpperCase();
+      return queryIncludeAny.any(key.contains) && queryExcludeAll.every((q) => !key.contains(q));
+    }
+
+    final filteredMetadata = Map.fromEntries(metadata.entries.map((kv) {
+      final filteredDir = kv.value.filterKeys(testKey);
+      return MapEntry(kv.key, filteredDir);
+    }));
+
+    final tiles = filteredMetadata.entries
+        .where((kv) => kv.value.tags.isNotEmpty)
+        .map((kv) => MetadataDirTile(
+              entry: entry,
+              title: kv.key,
+              dir: kv.value,
+              initiallyExpanded: true,
+              showPrefixChildren: false,
+            ))
+        .toList();
+    return tiles.isEmpty
+        ? EmptyContent(
+            icon: AIcons.info,
+            text: 'No matching keys',
+          )
+        : ListView.builder(
+            padding: EdgeInsets.all(8),
+            itemBuilder: (context, index) => tiles[index],
+            itemCount: tiles.length,
+          );
+  }
+}

lib/widgets/fullscreen/info/metadata/metadata_dir_tile.dart

@@ -0,0 +1,113 @@
+import 'dart:collection';
+
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/ref/brand_colors.dart';
+import 'package:aves/services/svg_metadata_service.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/utils/color_utils.dart';
+import 'package:aves/utils/constants.dart';
+import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
+import 'package:aves/widgets/fullscreen/info/common.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_section.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_thumbnail.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/xmp_tile.dart';
+import 'package:aves/widgets/fullscreen/source_viewer_page.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+
+class MetadataDirTile extends StatelessWidget {
+  final ImageEntry entry;
+  final String title;
+  final MetadataDirectory dir;
+  final ValueNotifier<String> expandedDirectoryNotifier;
+  final bool initiallyExpanded, showPrefixChildren;
+
+  const MetadataDirTile({
+    @required this.entry,
+    @required this.title,
+    @required this.dir,
+    this.expandedDirectoryNotifier,
+    this.initiallyExpanded = false,
+    this.showPrefixChildren = true,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final tags = dir.tags;
+    if (tags.isEmpty) return SizedBox.shrink();
+
+    final dirName = dir.name;
+    if (dirName == MetadataDirectory.xmpDirectory) {
+      return XmpDirTile(
+        entry: entry,
+        tags: tags,
+        expandedNotifier: expandedDirectoryNotifier,
+        initiallyExpanded: initiallyExpanded,
+      );
+    }
+
+    Widget thumbnail;
+    final prefixChildren = <Widget>[];
+    if (showPrefixChildren) {
+      switch (dirName) {
+        case MetadataDirectory.exifThumbnailDirectory:
+          thumbnail = MetadataThumbnails(source: MetadataThumbnailSource.exif, entry: entry);
+          break;
+        case MetadataDirectory.mediaDirectory:
+          thumbnail = MetadataThumbnails(source: MetadataThumbnailSource.embedded, entry: entry);
+          Widget builder(IconData data) => Padding(
+                padding: EdgeInsets.symmetric(vertical: 4, horizontal: 8),
+                child: Icon(data),
+              );
+          if (tags['Has Video'] == 'yes') prefixChildren.add(builder(AIcons.video));
+          if (tags['Has Audio'] == 'yes') prefixChildren.add(builder(AIcons.audio));
+          if (tags['Has Image'] == 'yes') {
+            int count;
+            if (tags.containsKey('Image Count')) {
+              count = int.tryParse(tags['Image Count']);
+            }
+            prefixChildren.addAll(List.generate(count ?? 1, (i) => builder(AIcons.image)));
+          }
+          break;
+      }
+    }
+
+    return AvesExpansionTile(
+      title: title,
+      color: BrandColors.get(dirName) ?? stringToColor(dirName),
+      expandedNotifier: expandedDirectoryNotifier,
+      initiallyExpanded: initiallyExpanded,
+      children: [
+        if (prefixChildren.isNotEmpty) Wrap(children: prefixChildren),
+        if (thumbnail != null) thumbnail,
+        Padding(
+          padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
+          child: InfoRowGroup(
+            tags,
+            maxValueLength: Constants.infoGroupMaxValueLength,
+            linkHandlers: dirName == SvgMetadataService.metadataDirectory ? getSvgLinkHandlers(tags) : null,
+          ),
+        ),
+      ],
+    );
+  }
+
+  static Map<String, InfoLinkHandler> getSvgLinkHandlers(SplayTreeMap<String, String> tags) {
+    return {
+      'Metadata': InfoLinkHandler(
+        linkText: 'View XML',
+        onTap: (context) {
+          Navigator.push(
+            context,
+            MaterialPageRoute(
+              settings: RouteSettings(name: SourceViewerPage.routeName),
+              builder: (context) => SourceViewerPage(
+                loader: () => SynchronousFuture(tags['Metadata']),
+              ),
+            ),
+          );
+        },
+      ),
+    };
+  }
+}

lib/widgets/fullscreen/info/metadata/metadata_section.dart

@@ -1,18 +1,12 @@
 import 'dart:collection';
 
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/ref/brand_colors.dart';
 import 'package:aves/services/metadata_service.dart';
 import 'package:aves/services/svg_metadata_service.dart';
 import 'package:aves/theme/durations.dart';
 import 'package:aves/theme/icons.dart';
-import 'package:aves/utils/color_utils.dart';
-import 'package:aves/utils/constants.dart';
-import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
 import 'package:aves/widgets/fullscreen/info/common.dart';
-import 'package:aves/widgets/fullscreen/info/metadata/metadata_thumbnail.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/metadata_dir_tile.dart';
-import 'package:aves/widgets/fullscreen/info/metadata/xmp_tile.dart';
-import 'package:aves/widgets/fullscreen/source_viewer_page.dart';
 import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
@@ -21,10 +15,12 @@ import 'package:flutter_staggered_animations/flutter_staggered_animations.dart';
 class MetadataSectionSliver extends StatefulWidget {
   final ImageEntry entry;
   final ValueNotifier<bool> visibleNotifier;
+  final ValueNotifier<Map<String, MetadataDirectory>> metadataNotifier;
 
   const MetadataSectionSliver({
     @required this.entry,
     @required this.visibleNotifier,
+    @required this.metadataNotifier,
   });
 
   @override
@@ -32,7 +28,6 @@ class MetadataSectionSliver extends StatefulWidget {
 }
 
 class _MetadataSectionSliverState extends State<MetadataSectionSliver> with AutomaticKeepAliveClientMixin {
-  Map<String, _MetadataDirectory> _metadata = {};
   final ValueNotifier<String> _loadedMetadataUri = ValueNotifier(null);
   final ValueNotifier<String> _expandedDirectoryNotifier = ValueNotifier(null);
 
@@ -40,10 +35,9 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
 
   bool get isVisible => widget.visibleNotifier.value;
 
-  // special directory names
+  ValueNotifier<Map<String, MetadataDirectory>> get metadataNotifier => widget.metadataNotifier;
-  static const exifThumbnailDirectory = 'Exif Thumbnail'; // from metadata-extractor
+
-  static const xmpDirectory = 'XMP'; // from metadata-extractor
+  Map<String, MetadataDirectory> get metadata => metadataNotifier.value;
-  static const mediaDirectory = 'Media'; // additional media (video/audio/images) directory
 
   // directory names may contain the name of their parent directory
   // if so, they are separated by this character
@@ -53,6 +47,7 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
   void initState() {
     super.initState();
     _registerWidget(widget);
+    metadataNotifier.value = {};
     _getMetadata();
   }
 
@@ -96,7 +91,7 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
           valueListenable: _loadedMetadataUri,
           builder: (context, uri, child) {
             Widget content;
-            if (_metadata.isEmpty) {
+            if (metadata.isEmpty) {
               content = SizedBox.shrink();
             } else {
               content = Column(
@@ -111,7 +106,12 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
                   ),
                   children: [
                     SectionRow(AIcons.info),
-                    ..._metadata.entries.map((kv) => _buildDirTile(kv.key, kv.value)),
+                    ...metadata.entries.map((kv) => MetadataDirTile(
+                          entry: entry,
+                          title: kv.key,
+                          dir: kv.value,
+                          expandedDirectoryNotifier: _expandedDirectoryNotifier,
+                        )),
                   ],
                 ),
               );
@@ -128,64 +128,9 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
     );
   }
 
-  Widget _buildDirTile(String title, _MetadataDirectory dir) {
-    if (dir.tags.isEmpty) return SizedBox.shrink();
-
-    final dirName = dir.name;
-    if (dirName == xmpDirectory) {
-      return XmpDirTile(
-        entry: entry,
-        tags: dir.tags,
-        expandedNotifier: _expandedDirectoryNotifier,
-      );
-    }
-
-    Widget thumbnail;
-    final prefixChildren = <Widget>[];
-    switch (dirName) {
-      case exifThumbnailDirectory:
-        thumbnail = MetadataThumbnails(source: MetadataThumbnailSource.exif, entry: entry);
-        break;
-      case mediaDirectory:
-        thumbnail = MetadataThumbnails(source: MetadataThumbnailSource.embedded, entry: entry);
-        Widget builder(IconData data) => Padding(
-              padding: EdgeInsets.symmetric(vertical: 4, horizontal: 8),
-              child: Icon(data),
-            );
-        if (dir.tags['Has Video'] == 'yes') prefixChildren.add(builder(AIcons.video));
-        if (dir.tags['Has Audio'] == 'yes') prefixChildren.add(builder(AIcons.audio));
-        if (dir.tags['Has Image'] == 'yes') {
-          int count;
-          if (dir.tags.containsKey('Image Count')) {
-            count = int.tryParse(dir.tags['Image Count']);
-          }
-          prefixChildren.addAll(List.generate(count ?? 1, (i) => builder(AIcons.image)));
-        }
-        break;
-    }
-
-    return AvesExpansionTile(
-      title: title,
-      color: BrandColors.get(dirName) ?? stringToColor(dirName),
-      expandedNotifier: _expandedDirectoryNotifier,
-      children: [
-        if (prefixChildren.isNotEmpty) Wrap(children: prefixChildren),
-        if (thumbnail != null) thumbnail,
-        Padding(
-          padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
-          child: InfoRowGroup(
-            dir.tags,
-            maxValueLength: Constants.infoGroupMaxValueLength,
-            linkHandlers: dirName == SvgMetadataService.metadataDirectory ? getSvgLinkHandlers(dir.tags) : null,
-          ),
-        ),
-      ],
-    );
-  }
-
   void _onMetadataChanged() {
     _loadedMetadataUri.value = null;
-    _metadata = {};
+    metadataNotifier.value = {};
     _getMetadata();
   }
 
@@ -211,7 +156,7 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
           final tagName = tagKV.key as String ?? '';
           return MapEntry(tagName, value);
         }).where((kv) => kv != null)));
-        return _MetadataDirectory(directoryName, parent, tags);
+        return MetadataDirectory(directoryName, parent, tags);
       }).toList();
 
       final titledDirectories = directories.map((dir) {
@@ -222,42 +167,36 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
         return MapEntry(title, dir);
       }).toList()
         ..sort((a, b) => compareAsciiUpperCase(a.key, b.key));
-      _metadata = Map.fromEntries(titledDirectories);
+      metadataNotifier.value = Map.fromEntries(titledDirectories);
       _loadedMetadataUri.value = entry.uri;
     } else {
-      _metadata = {};
+      metadataNotifier.value = {};
       _loadedMetadataUri.value = null;
     }
     _expandedDirectoryNotifier.value = null;
   }
 
-  static Map<String, InfoLinkHandler> getSvgLinkHandlers(SplayTreeMap<String, String> tags) {
-    return {
-      'Metadata': InfoLinkHandler(
-        linkText: 'View XML',
-        onTap: (context) {
-          Navigator.push(
-            context,
-            MaterialPageRoute(
-              settings: RouteSettings(name: SourceViewerPage.routeName),
-              builder: (context) => SourceViewerPage(
-                loader: () => SynchronousFuture(tags['Metadata']),
-              ),
-            ),
-          );
-        },
-      ),
-    };
-  }
-
   @override
   bool get wantKeepAlive => true;
 }
 
-class _MetadataDirectory {
+class MetadataDirectory {
   final String name;
   final String parent;
+  final SplayTreeMap<String, String> allTags;
   final SplayTreeMap<String, String> tags;
 
-  const _MetadataDirectory(this.name, this.parent, this.tags);
+  // special directory names
+  static const exifThumbnailDirectory = 'Exif Thumbnail'; // from metadata-extractor
+  static const xmpDirectory = 'XMP'; // from metadata-extractor
+  static const mediaDirectory = 'Media'; // additional media (video/audio/images) directory
+
+  const MetadataDirectory(this.name, this.parent, SplayTreeMap<String, String> allTags, {SplayTreeMap<String, String> tags})
+      : allTags = allTags,
+        tags = tags ?? allTags;
+
+  MetadataDirectory filterKeys(bool Function(String key) testKey) {
+    final filteredTags = SplayTreeMap.of(Map.fromEntries(allTags.entries.where((kv) => testKey(kv.key))));
+    return MetadataDirectory(name, parent, tags, tags: filteredTags);
+  }
 }

lib/widgets/fullscreen/info/metadata/xmp_ns/xmp.dart

@@ -51,9 +51,13 @@ class XmpMMNamespace extends XmpNamespace {
 
   static final derivedFromPattern = RegExp(r'xmpMM:DerivedFrom/(.*)');
   static final historyPattern = RegExp(r'xmpMM:History\[(\d+)\]/(.*)');
+  static final ingredientsPattern = RegExp(r'xmpMM:Ingredients\[(\d+)\]/(.*)');
+  static final pantryPattern = RegExp(r'xmpMM:Pantry\[(\d+)\]/(.*)');
 
   final derivedFrom = <String, String>{};
   final history = <int, Map<String, String>>{};
+  final ingredients = <int, Map<String, String>>{};
+  final pantry = <int, Map<String, String>>{};
 
   XmpMMNamespace() : super(ns);
 
@@ -63,7 +67,9 @@ class XmpMMNamespace extends XmpNamespace {
   @override
   bool extractData(XmpProp prop) {
     final hasStructs = extractStruct(prop, derivedFromPattern, derivedFrom);
-    final hasIndexedStructs = extractIndexedStruct(prop, historyPattern, history);
+    var hasIndexedStructs = extractIndexedStruct(prop, historyPattern, history);
+    hasIndexedStructs |= extractIndexedStruct(prop, ingredientsPattern, ingredients);
+    hasIndexedStructs |= extractIndexedStruct(prop, pantryPattern, pantry);
     return hasStructs || hasIndexedStructs;
   }
 
@@ -79,6 +85,16 @@ class XmpMMNamespace extends XmpNamespace {
             title: 'History',
             structByIndex: history,
           ),
+        if (ingredients.isNotEmpty)
+          XmpStructArrayCard(
+            title: 'Ingredients',
+            structByIndex: ingredients,
+          ),
+        if (pantry.isNotEmpty)
+          XmpStructArrayCard(
+            title: 'Pantry',
+            structByIndex: pantry,
+          ),
       ];
 
   @override

lib/widgets/fullscreen/info/metadata/xmp_structs.dart

@@ -89,7 +89,7 @@ class _XmpStructArrayCardState extends State<XmpStructArrayCard> {
               // without clipping the text
               padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
               child: InfoRowGroup(
-                structs[_index],
+                structs[_index] ?? {},
                 maxValueLength: Constants.infoGroupMaxValueLength,
                 linkHandlers: widget.linkifier?.call(_index + 1),
               ),

lib/widgets/fullscreen/info/metadata/xmp_tile.dart

@@ -25,11 +25,13 @@ class XmpDirTile extends StatefulWidget {
   final ImageEntry entry;
   final SplayTreeMap<String, String> tags;
   final ValueNotifier<String> expandedNotifier;
+  final bool initiallyExpanded;
 
   const XmpDirTile({
     @required this.entry,
     @required this.tags,
     @required this.expandedNotifier,
+    @required this.initiallyExpanded,
   });
 
   @override
@@ -76,6 +78,7 @@ class _XmpDirTileState extends State<XmpDirTile> with FeedbackMixin {
     return AvesExpansionTile(
       title: 'XMP',
       expandedNotifier: widget.expandedNotifier,
+      initiallyExpanded: widget.initiallyExpanded,
       children: [
         NotificationListener<OpenEmbeddedDataNotification>(
           onNotification: (notification) {

lib/widgets/home_page.dart

@@ -142,7 +142,7 @@ class _HomePageState extends State<HomePage> {
         );
       case SearchPage.routeName:
         return SearchPageRoute(
-          delegate: ImageSearchDelegate(source: _mediaStore),
+          delegate: CollectionSearchDelegate(source: _mediaStore),
         );
       case CollectionPage.routeName:
       default:

lib/widgets/search/search_button.dart

@@ -4,11 +4,11 @@ import 'package:aves/theme/icons.dart';
 import 'package:aves/widgets/search/search_delegate.dart';
 import 'package:flutter/material.dart';
 
-class SearchButton extends StatelessWidget {
+class CollectionSearchButton extends StatelessWidget {
   final CollectionSource source;
   final CollectionLens parentCollection;
 
-  const SearchButton(this.source, {this.parentCollection});
+  const CollectionSearchButton(this.source, {this.parentCollection});
 
   @override
   Widget build(BuildContext context) {
@@ -24,7 +24,7 @@ class SearchButton extends StatelessWidget {
     Navigator.push(
         context,
         SearchPageRoute(
-          delegate: ImageSearchDelegate(
+          delegate: CollectionSearchDelegate(
             source: source,
             parentCollection: parentCollection,
           ),

lib/widgets/search/search_delegate.dart

@@ -20,14 +20,14 @@ import 'package:aves/widgets/search/search_page.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
-class ImageSearchDelegate {
+class CollectionSearchDelegate {
   final CollectionSource source;
   final CollectionLens parentCollection;
   final ValueNotifier<String> expandedSectionNotifier = ValueNotifier(null);
 
   static const searchHistoryCount = 10;
 
-  ImageSearchDelegate({@required this.source, this.parentCollection});
+  CollectionSearchDelegate({@required this.source, this.parentCollection});
 
   ThemeData appBarTheme(BuildContext context) {
     return Theme.of(context);
@@ -289,7 +289,7 @@ class SearchPageRoute<T> extends PageRoute<T> {
     delegate.route = this;
   }
 
-  final ImageSearchDelegate delegate;
+  final CollectionSearchDelegate delegate;
 
   @override
   Color get barrierColor => null;

lib/widgets/search/search_page.dart

@@ -7,7 +7,7 @@ import 'package:flutter/material.dart';
 class SearchPage extends StatefulWidget {
   static const routeName = '/search';
 
-  final ImageSearchDelegate delegate;
+  final CollectionSearchDelegate delegate;
   final Animation<double> animation;
 
   const SearchPage({
@@ -115,7 +115,7 @@ class _SearchPageState extends State<SearchPage> {
           onSubmitted: (_) => widget.delegate.showResults(context),
           decoration: InputDecoration(
             border: InputBorder.none,
-            hintText: MaterialLocalizations.of(context).searchFieldLabel,
+            hintText: 'Search collection',
             hintStyle: theme.inputDecorationTheme.hintStyle,
           ),
         ),

pubspec.yaml

@@ -3,7 +3,7 @@ description: Aves is a gallery and metadata explorer app, built for Android.
 
 publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 
-version: 1.3.0+36
+version: 1.3.1+37
 
 # brendan-duncan/image (as of v2.1.19):
 # - does not support TIFF with JPEG compression (issue #184)

whatsnew/whatsnew-en-US

@@ -1,5 +1,6 @@
 Thanks for using Aves!
-v1.3.0:
+v1.3.1:
-- added quick scale (aka one finger zoom) gesture to the viewer
+- long press and move to select/deselect multiple entries
-- fixed zoom focus with double-tap or pinch-to-zoom gestures
+- metadata search in the Info page
+- fixed crash when opening a collection with TIFF files on Android 11
 Full changelog available on Github