ui: further apply elevation overlays

Apply elevation overlays to CompactPlaybackFragment and dragged queue
items. This makes elevation more noticable on dark mode.

app/src/main/java/org/oxycblt/auxio/MainFragment.kt

@@ -27,9 +27,9 @@ import androidx.core.view.updatePadding
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import org.oxycblt.auxio.databinding.FragmentMainBinding
-import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.util.applyEdge
+import org.oxycblt.auxio.util.applyMaterialDrawable
 import org.oxycblt.auxio.util.logD
 
 /**
@@ -51,29 +51,24 @@ class MainFragment : Fragment() {
         binding.lifecycleOwner = viewLifecycleOwner
 
         binding.applyEdge { bars ->
-            binding.root.updatePadding(bottom = bars.bottom)
+            binding.mainPlayback.updatePadding(bottom = bars.bottom)
         }
 
+        binding.mainPlayback.applyMaterialDrawable()
+
         // --- VIEWMODEL SETUP ---
 
         playbackModel.setupPlayback(requireContext())
 
         // Change CompactPlaybackFragment's visibility here so that an animation occurs.
-        handleCompactPlaybackVisibility(binding, playbackModel.song.value)
+        binding.mainPlayback.isVisible = playbackModel.song.value != null
 
         playbackModel.song.observe(viewLifecycleOwner) { song ->
-            handleCompactPlaybackVisibility(binding, song)
+            binding.mainPlayback.isVisible = song != null
         }
 
         logD("Fragment Created.")
 
         return binding.root
     }
-
-    /**
-     * Handle the visibility of CompactPlaybackFragment. Done here so that there's a nice animation.
-     */
-    private fun handleCompactPlaybackVisibility(binding: FragmentMainBinding, song: Song?) {
-        binding.mainPlayback.isVisible = song != null
-    }
 }

app/src/main/java/org/oxycblt/auxio/playback/queue/QueueAdapter.kt

@@ -35,6 +35,7 @@ import org.oxycblt.auxio.playback.PlaybackViewModel
 import org.oxycblt.auxio.ui.BaseViewHolder
 import org.oxycblt.auxio.ui.DiffCallback
 import org.oxycblt.auxio.ui.HeaderViewHolder
+import org.oxycblt.auxio.util.applyMaterialDrawable
 import org.oxycblt.auxio.util.inflater
 import org.oxycblt.auxio.util.logE
 
@@ -158,6 +159,10 @@ class QueueAdapter(
         private val binding: ItemQueueSongBinding,
     ) : BaseViewHolder<Song>(binding) {
 
+        init {
+            binding.root.applyMaterialDrawable()
+        }
+
         @SuppressLint("ClickableViewAccessibility")
         override fun onBind(data: Song) {
             binding.song = data

app/src/main/java/org/oxycblt/auxio/playback/queue/QueueDragCallback.kt

@@ -20,10 +20,9 @@ package org.oxycblt.auxio.playback.queue
 
 import android.graphics.Canvas
 import android.view.animation.AccelerateDecelerateInterpolator
-import androidx.coordinatorlayout.widget.CoordinatorLayout
 import androidx.recyclerview.widget.ItemTouchHelper
 import androidx.recyclerview.widget.RecyclerView
-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
 import kotlin.math.abs
@@ -36,13 +35,8 @@ import kotlin.math.sign
  * of the UI magic that makes up the queue UI.
  * @author OxygenCobalt
  */
-class QueueDragCallback(
-    private val playbackModel: PlaybackViewModel,
-    private val coordinator: CoordinatorLayout,
-    private val appBar: AppBarLayout
-) : ItemTouchHelper.Callback() {
+class QueueDragCallback(private val playbackModel: PlaybackViewModel) : ItemTouchHelper.Callback() {
     private lateinit var queueAdapter: QueueAdapter
-    private val tConsumed = IntArray(2)
     private var shouldLift = true
 
     override fun getMovementFlags(
@@ -100,9 +94,12 @@ class QueueDragCallback(
         val view = viewHolder.itemView
 
         if (shouldLift && isCurrentlyActive && actionState == ItemTouchHelper.ACTION_STATE_DRAG) {
+            val bg = view.background as MaterialShapeDrawable
+
             view.animate()
                 .translationZ(view.resources.getDimension(R.dimen.elevation_small))
                 .setDuration(100)
+                .setUpdateListener { bg.elevation = view.translationZ }
                 .setInterpolator(AccelerateDecelerateInterpolator())
                 .start()
 
@@ -118,9 +115,12 @@ class QueueDragCallback(
         val view = viewHolder.itemView
 
         if (view.translationZ != 0.0f) {
+            val bg = view.background as MaterialShapeDrawable
+
             view.animate()
                 .translationZ(0.0f)
                 .setDuration(100)
+                .setUpdateListener { bg.elevation = view.translationZ }
                 .setInterpolator(AccelerateDecelerateInterpolator())
                 .start()
         }

app/src/main/java/org/oxycblt/auxio/playback/queue/QueueFragment.kt

@@ -50,11 +50,7 @@ class QueueFragment : Fragment() {
     ): View {
         val binding = FragmentQueueBinding.inflate(inflater)
 
-        val callback = QueueDragCallback(
-            playbackModel,
-            binding.queueCoordinator,
-            binding.queueAppbar
-        )
+        val callback = QueueDragCallback(playbackModel)
 
         val helper = ItemTouchHelper(callback)
         val queueAdapter = QueueAdapter(helper, playbackModel)

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

@@ -22,6 +22,7 @@ import android.content.Context
 import android.content.res.ColorStateList
 import android.content.res.Resources
 import android.graphics.Rect
+import android.graphics.drawable.ColorDrawable
 import android.os.Build
 import android.util.TypedValue
 import android.view.View
@@ -35,8 +36,23 @@ 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
 
+/**
+ * Apply a [MaterialShapeDrawable] to this view, automatically initializing the elevation overlay
+ * and setting the fill color. This assumes that the background is a [ColorDrawable] and will
+ * crash if not.
+ */
+fun View.applyMaterialDrawable() {
+    check(background is ColorDrawable) { "Background was not defined as a solid color" }
+
+    background = MaterialShapeDrawable.createWithElevationOverlay(context).apply {
+        elevation = this@applyMaterialDrawable.elevation
+        fillColor = ColorStateList.valueOf((background as ColorDrawable).color)
+    }
+}
+
 /**
  * Apply the recommended spans for a [RecyclerView].
  *
@@ -65,6 +81,11 @@ fun RecyclerView.applySpans(shouldBeFullWidth: ((Int) -> Boolean)? = null) {
     }
 }
 
+/**
+ * Returns whether a recyclerview can scroll.
+ */
+fun RecyclerView.canScroll(): Boolean = computeVerticalScrollRange() > height
+
 /**
  * Disable an image button.
  * TODO: Replace this fragile function with something else.
@@ -75,10 +96,6 @@ fun ImageButton.disable() {
         isEnabled = false
     }
 }
-/**
- * Returns whether a recyclerview can scroll.
- */
-fun RecyclerView.canScroll(): Boolean = computeVerticalScrollRange() > height
 
 /**
  * Resolve a color.

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

@@ -25,9 +25,10 @@
             android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:elevation="@dimen/elevation_normal"
-            android:clipToPadding="true"
             android:background="?attr/colorSurface"
+            android:clipToPadding="true"
+            android:elevation="@dimen/elevation_normal"
             tools:layout="@layout/fragment_compact_playback" />
+
     </LinearLayout>
 </layout>