ui: add edge-to-edge on bar-dependent fragments

Add edge-to-edge on the Home, Detail, and Search fragments. This
solution is not ideal at all, relying on viewModel state to make
sure that the padding is only applied when the playback bar is not
present. However, it works. I'll likely replace it with a better
layout once I can figure out how similar layouts like Material
Files' PersistentBarLyout work.

app/src/main/java/org/oxycblt/auxio/detail/DetailFragment.kt

@@ -36,6 +36,7 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.SortMode
 import org.oxycblt.auxio.ui.memberBinding
 import org.oxycblt.auxio.util.applyEdge
+import org.oxycblt.auxio.util.applyEdgeRespectingBar
 import org.oxycblt.auxio.util.isLandscape
 
 /**
@@ -52,6 +53,8 @@ abstract class DetailFragment : Fragment() {
             binding.detailAppbar.updatePadding(top = bars.top)
         }
 
+        binding.detailRecycler.applyEdgeRespectingBar(playbackModel, viewLifecycleOwner)
+
         requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, callback)
     }
 

app/src/main/java/org/oxycblt/auxio/home/list/HomeListFragment.kt

@@ -34,6 +34,7 @@ import org.oxycblt.auxio.home.HomeViewModel
 import org.oxycblt.auxio.music.BaseModel
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.memberBinding
+import org.oxycblt.auxio.util.applyEdgeRespectingBar
 import org.oxycblt.auxio.util.applySpans
 import org.oxycblt.auxio.util.resolveDrawable
 
@@ -73,6 +74,7 @@ abstract class HomeListFragment : Fragment() {
             adapter = homeAdapter
             setHasFixedSize(true)
             applySpans()
+            applyEdgeRespectingBar(playbackModel, viewLifecycleOwner)
         }
 
         // Make sure that this RecyclerView has data before startup

app/src/main/java/org/oxycblt/auxio/search/SearchFragment.kt

@@ -43,6 +43,7 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.DisplayMode
 import org.oxycblt.auxio.ui.newMenu
 import org.oxycblt.auxio.util.applyEdge
+import org.oxycblt.auxio.util.applyEdgeRespectingBar
 import org.oxycblt.auxio.util.applySpans
 import org.oxycblt.auxio.util.getSystemServiceSafe
 import org.oxycblt.auxio.util.logD
@@ -126,6 +127,8 @@ class SearchFragment : Fragment() {
             applySpans { pos ->
                 searchAdapter.currentList[pos] is Header
             }
+
+            applyEdgeRespectingBar(playbackModel, viewLifecycleOwner)
         }
 
         // --- VIEWMODEL SETUP ---

app/src/main/java/org/oxycblt/auxio/util/ViewUtil.kt

@@ -32,12 +32,14 @@ import androidx.annotation.ColorInt
 import androidx.annotation.ColorRes
 import androidx.annotation.DrawableRes
 import androidx.core.content.ContextCompat
+import androidx.core.view.updatePadding
+import androidx.lifecycle.LifecycleOwner
 import androidx.recyclerview.widget.GridLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import androidx.viewbinding.ViewBinding
-import com.google.android.material.appbar.AppBarLayout
 import com.google.android.material.shape.MaterialShapeDrawable
 import org.oxycblt.auxio.R
+import org.oxycblt.auxio.playback.PlaybackViewModel
 
 /**
  * Apply a [MaterialShapeDrawable] to this view, automatically initializing the elevation overlay
@@ -140,19 +142,6 @@ fun @receiver:AttrRes Int.resolveAttr(context: Context): Int {
     return color.resolveColor(context)
 }
 
-/**
- * Make this [AppBarLayout] fade a scrolling [view] out when it collapses.
- * This is mostly because I am unable to figure out how to get a collapsing view not
- * to draw under the status bar in edge-to-edge mode.
- */
-fun AppBarLayout.makeScrollingViewFade(view: View) {
-    addOnOffsetChangedListener(
-        AppBarLayout.OnOffsetChangedListener { _, verticalOffset ->
-            view.alpha = (view.height + verticalOffset) / view.height.toFloat()
-        }
-    )
-}
-
 /**
  * Apply edge-to-edge tweaks to the root of a [ViewBinding].
  * @param onApply What to do when the system bar insets are provided
@@ -197,3 +186,36 @@ fun View.applyEdge(onApply: (Rect) -> Unit) {
         // Not on a version that supports edge-to-edge [yet], don't do anything
     }
 }
+
+/**
+ * Stopgap measure to make edge-to-edge work on views that also have a playback bar.
+ * The issue is that while we can apply padding initially, the padding will still be applied
+ * when the bar is shown, which is very ungood. We mitigate this by just checking the song state
+ * and removing the padding if it isnt available, which works okayish. I think Material Files has
+ * a better implementation of the same fix however, so once I'm able to hack that layout into
+ * Auxio things should be better.
+ */
+fun RecyclerView.applyEdgeRespectingBar(
+    playbackModel: PlaybackViewModel,
+    viewLifecycleOwner: LifecycleOwner
+) {
+    var bottomPadding = 0
+
+    applyEdge {
+        bottomPadding = it.bottom
+
+        if (playbackModel.song.value == null) {
+            updatePadding(bottom = bottomPadding)
+        } else {
+            updatePadding(bottom = 0)
+        }
+    }
+
+    playbackModel.song.observe(viewLifecycleOwner) { song ->
+        if (song == null) {
+            updatePadding(bottom = bottomPadding)
+        } else {
+            updatePadding(bottom = 0)
+        }
+    }
+}

app/src/main/res/layout/fragment_search.xml

@@ -51,6 +51,7 @@
             android:id="@+id/search_recycler"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
+            android:clipToPadding="false"
             app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
             app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior"
             tools:listitem="@layout/item_song" />