Redo controls view

Redo the controls view to support a slide enter/exit animation, along with fixes to elevation problems on certain devices.

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

@@ -1,5 +1,6 @@
 package org.oxycblt.auxio
 
+import android.animation.LayoutTransition
 import android.content.res.ColorStateList
 import android.os.Bundle
 import android.view.LayoutInflater
@@ -9,6 +10,7 @@ import android.view.ViewGroup
 import androidx.core.graphics.ColorUtils
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
+import androidx.interpolator.view.animation.FastOutSlowInInterpolator
 import androidx.navigation.NavController
 import androidx.navigation.NavOptions
 import androidx.navigation.fragment.NavHostFragment
@@ -69,6 +71,13 @@ class MainFragment : Fragment() {
 
         binding.lifecycleOwner = this
 
+        // Apply custom interpolation effects
+        // The container layout types differ in the land/port layouts so it has to be cast to their parent instead.
+        (binding.controlsContainer as ViewGroup).layoutTransition = LayoutTransition().apply {
+            setInterpolator(LayoutTransition.APPEARING, FastOutSlowInInterpolator())
+            setInterpolator(LayoutTransition.DISAPPEARING, FastOutSlowInInterpolator())
+        }
+
         binding.navBar.apply {
             itemIconTintList = navTints
             itemTextColor = navTints
@@ -150,7 +159,9 @@ class MainFragment : Fragment() {
         if (song == null) {
             logD("Hiding CompactPlaybackFragment since no song is being played.")
 
-            if (!isLandscape(resources)) {
+            if (isLandscape(resources)) {
+                binding.compactPlayback.visibility = View.INVISIBLE
+            } else {
                 binding.compactPlayback.visibility = View.GONE
             }
 

app/src/main/java/org/oxycblt/auxio/playback/CompactPlaybackFragment.kt

@@ -57,10 +57,6 @@ class CompactPlaybackFragment : Fragment() {
             }
         }
 
-        if (playbackModel.song.value == null) {
-            setInvisible(true)
-        }
-
         // --- VIEWMODEL SETUP ---
 
         playbackModel.song.observe(viewLifecycleOwner) {
@@ -69,9 +65,6 @@ class CompactPlaybackFragment : Fragment() {
 
                 binding.song = it
                 binding.playbackProgress.max = it.seconds.toInt()
-                setInvisible(false)
-            } else {
-                setInvisible(true)
             }
         }
 
@@ -117,20 +110,4 @@ class CompactPlaybackFragment : Fragment() {
             }
         }
     }
-
-    /**
-     * Set this fragment to be invisible, if needed. Only runs in landscape mode.
-     */
-    private fun setInvisible(invisible: Boolean) {
-        // Does not run in landscape
-        if (!isLandscape(resources)) return
-
-        val visibility = if (invisible) View.INVISIBLE else View.VISIBLE
-
-        binding.playbackLayout.children.forEach {
-            it.visibility = visibility
-        }
-
-        binding.root.isEnabled = !invisible
-    }
 }

app/src/main/java/org/oxycblt/auxio/ui/SlideLinearLayout.kt

@@ -0,0 +1,98 @@
+package org.oxycblt.auxio.ui
+
+import android.content.Context
+import android.graphics.Canvas
+import android.util.AttributeSet
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import org.oxycblt.auxio.logD
+import org.oxycblt.auxio.logE
+import java.lang.reflect.Field
+
+/**
+ * Hack layout that fixes an issue where disappearing views would draw over non-disappearing
+ * views when animated with a stock LayoutTransition. Adapted from this StackOverflow answer:
+ * https://stackoverflow.com/a/35087229
+ */
+class SlideLinearLayout @JvmOverloads constructor(
+    context: Context,
+    attrs: AttributeSet? = null,
+    defStyleAttr: Int = -1
+) : LinearLayout(context, attrs, defStyleAttr) {
+    private val disappearingChildrenField: Field? = try {
+        ViewGroup::class.java.getDeclaredField("mDisappearingChildren").also {
+            it.isAccessible = true
+        }
+    } catch (e: NoSuchFieldException) {
+        logE("Could not get mDisappearingChildren.")
+        null
+    }
+
+    private var disappearingChildren: List<View>? = null
+
+    private var dumpView: View? = null
+    private var doDrawingTrick: Boolean = false
+
+    init {
+        if (disappearingChildrenField != null) {
+            // Create a junk view and add it, which makes all the magic happen [I think??].
+            dumpView = View(context)
+            addView(dumpView, 0, 0)
+        }
+    }
+
+    override fun dispatchDraw(canvas: Canvas?) {
+        doDrawingTrick = beforeDispatchDraw()
+        super.dispatchDraw(canvas)
+
+        if (doDrawingTrick) {
+            doDrawingTrick = false
+        }
+    }
+
+    override fun drawChild(canvas: Canvas?, child: View?, drawingTime: Long): Boolean {
+        val children = getDisappearingChildren()
+
+        // I have no idea what this code does.
+        if (doDrawingTrick && children != null) {
+            if (child == dumpView) {
+                var more = false
+                children.forEach {
+                    more = more or super.drawChild(canvas, it, drawingTime)
+                }
+                return more
+            } else if (children.contains(child)) {
+                return false
+            }
+        }
+
+        return super.drawChild(canvas, child, drawingTime)
+    }
+
+    private fun beforeDispatchDraw(): Boolean {
+        val children = getDisappearingChildren()
+
+        if (children == null || children.isEmpty() || childCount <= 1) { // Junk view included
+            return false
+        }
+
+        return true
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    private fun getDisappearingChildren(): List<View>? {
+        if (disappearingChildrenField == null || disappearingChildren != null) {
+            return disappearingChildren
+        }
+
+        // If there is no list of disappearing children yet, attempt to get it.
+        try {
+            disappearingChildren = disappearingChildrenField.get(this) as List<View>?
+        } catch (e: IllegalAccessException) {
+            logD("Could not get list of disappearing children.")
+        }
+
+        return disappearingChildren
+    }
+}

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

@@ -17,34 +17,41 @@
             android:name="androidx.navigation.fragment.NavHostFragment"
             android:layout_width="match_parent"
             android:layout_height="0dp"
-            app:layout_constraintBottom_toTopOf="@+id/compact_playback"
+            app:layout_constraintBottom_toTopOf="@+id/controls_container"
             app:layout_constraintTop_toTopOf="parent"
             app:navGraph="@navigation/nav_explore"
             tools:layout="@layout/fragment_library" />
 
-        <androidx.fragment.app.FragmentContainerView
-            android:id="@+id/compact_playback"
-            android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
-            android:layout_width="0dp"
+        <LinearLayout
+            android:id="@+id/controls_container"
+            android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:orientation="horizontal"
             android:background="?android:attr/windowBackground"
-            android:elevation="@dimen/elevation_high"
-            android:outlineProvider="bounds"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toEndOf="@+id/nav_bar"
-            tools:layout="@layout/fragment_compact_playback" />
+            android:baselineAligned="false"
+            android:animateLayoutChanges="true"
+            android:elevation="@dimen/elevation_normal"
+            app:layout_constraintBottom_toBottomOf="parent">
 
-        <com.google.android.material.bottomnavigation.BottomNavigationView
-            android:id="@+id/nav_bar"
-            android:layout_width="wrap_content"
-            android:layout_height="0dp"
-            android:background="@color/background"
-            app:labelVisibilityMode="selected"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintTop_toTopOf="@+id/compact_playback"
-            app:menu="@menu/menu_nav" />
+            <com.google.android.material.bottomnavigation.BottomNavigationView
+                android:id="@+id/nav_bar"
+                android:layout_width="0dp"
+                android:layout_height="match_parent"
+                android:background="@color/background"
+                android:elevation="0dp"
+                app:elevation="0dp"
+                android:layout_weight="1.5"
+                app:menu="@menu/menu_nav" />
+
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/compact_playback"
+                android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="2"
+                tools:layout="@layout/fragment_compact_playback" />
+
+        </LinearLayout>
 
     </androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

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

@@ -17,33 +17,40 @@
             android:name="androidx.navigation.fragment.NavHostFragment"
             android:layout_width="match_parent"
             android:layout_height="0dp"
-            app:layout_constraintBottom_toTopOf="@+id/compact_playback"
+            app:layout_constraintBottom_toTopOf="@+id/controls_container"
             app:layout_constraintTop_toTopOf="parent"
             app:navGraph="@navigation/nav_explore"
             tools:layout="@layout/fragment_library" />
 
-        <androidx.fragment.app.FragmentContainerView
-            android:id="@+id/compact_playback"
-            android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
+        <org.oxycblt.auxio.ui.SlideLinearLayout
+            android:id="@+id/controls_container"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:orientation="vertical"
             android:background="?android:attr/windowBackground"
-            android:elevation="@dimen/elevation_high"
-            android:outlineProvider="bounds"
-            app:layout_constraintBottom_toTopOf="@+id/nav_bar"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toStartOf="parent"
-            tools:layout="@layout/fragment_compact_playback" />
+            android:animateLayoutChanges="true"
+            android:elevation="@dimen/elevation_normal"
+            app:layout_constraintBottom_toBottomOf="parent">
 
-        <com.google.android.material.bottomnavigation.BottomNavigationView
-            android:id="@+id/nav_bar"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:background="@color/background"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toStartOf="parent"
-            app:menu="@menu/menu_nav" />
+            <androidx.fragment.app.FragmentContainerView
+                android:id="@+id/compact_playback"
+                android:name="org.oxycblt.auxio.playback.CompactPlaybackFragment"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                app:layout_constraintBottom_toTopOf="@+id/nav_bar"
+                tools:layout="@layout/fragment_compact_playback" />
 
+            <com.google.android.material.bottomnavigation.BottomNavigationView
+                android:id="@+id/nav_bar"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_gravity="bottom"
+                android:background="@color/background"
+                android:elevation="0dp"
+                app:elevation="0dp"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:menu="@menu/menu_nav" />
+
+        </org.oxycblt.auxio.ui.SlideLinearLayout>
     </androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

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

@@ -49,7 +49,6 @@
             </com.google.android.material.textfield.TextInputLayout>
         </com.google.android.material.appbar.AppBarLayout>
 
-
         <androidx.recyclerview.widget.RecyclerView
             android:id="@+id/search_recycler"
             android:layout_width="match_parent"