Motion: Support predictive back in Container transform

Motion/app/build.gradle

@@ -19,12 +19,12 @@ apply plugin: 'kotlin-android'
 apply plugin: "androidx.navigation.safeargs.kotlin"
 
 android {
-    compileSdk 31
+    compileSdk 34
 
     defaultConfig {
-        applicationId 'com.example.android.motion'
-        minSdk 14
-        targetSdk 31
+        namespace 'com.example.android.motion'
+        minSdk 19
+        targetSdk 34
         versionCode 1
         versionName '1.0'
         testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
@@ -51,33 +51,33 @@ android {
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
 
-    implementation 'androidx.core:core-ktx:1.7.0'
-    implementation 'androidx.fragment:fragment-ktx:1.4.1'
-    implementation 'androidx.appcompat:appcompat:1.4.1'
+    implementation 'androidx.core:core-ktx:1.12.0'
+    implementation 'androidx.fragment:fragment-ktx:1.6.2'
+    implementation 'androidx.appcompat:appcompat:1.6.1'
     implementation 'androidx.transition:transition:1.4.1'
     implementation 'androidx.dynamicanimation:dynamicanimation:1.1.0-alpha03'
-    implementation 'androidx.recyclerview:recyclerview:1.2.1'
+    implementation 'androidx.recyclerview:recyclerview:1.3.2'
 
-    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
+    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
 
-    def lifecycle_version = '2.4.1'
+    def lifecycle_version = '2.7.0'
     implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version"
     implementation "androidx.lifecycle:lifecycle-livedata-ktx:$lifecycle_version"
 
-    implementation 'androidx.paging:paging-runtime-ktx:3.1.1'
+    implementation 'androidx.paging:paging-runtime-ktx:3.2.1'
 
-    implementation 'com.google.android.material:material:1.6.0'
+    implementation 'com.google.android.material:material:1.11.0'
 
     implementation "androidx.navigation:navigation-fragment-ktx:$navigation_version"
     implementation "androidx.navigation:navigation-ui-ktx:$navigation_version"
 
-    implementation 'com.github.bumptech.glide:glide:4.10.0'
+    implementation 'com.github.bumptech.glide:glide:4.15.1'
 
     testImplementation 'junit:junit:4.13.2'
     testImplementation 'com.google.truth:truth:1.1.3'
 
-    testImplementation 'androidx.test:core:1.4.0'
-    androidTestImplementation 'androidx.test.ext:truth:1.4.0'
-    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
+    testImplementation 'androidx.test:core:1.5.0'
+    androidTestImplementation 'androidx.test.ext:truth:1.5.0'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
 }

Motion/app/src/main/AndroidManifest.xml

@@ -27,12 +27,14 @@
 
     <application
         android:allowBackup="false"
+        android:enableOnBackInvokedCallback="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.Motion"
-        tools:ignore="GoogleAppIndexingWarning">
+        tools:ignore="GoogleAppIndexingWarning"
+        tools:targetApi="34">
 
         <activity
             android:name=".MainActivity"

Motion/app/src/main/java/com/example/android/motion/demo/containertransform/CheeseArticleFragment.kt

@@ -24,17 +24,21 @@ import android.widget.FrameLayout
 import android.widget.ImageView
 import android.widget.LinearLayout
 import android.widget.TextView
+import androidx.activity.BackEventCompat
+import androidx.activity.OnBackPressedCallback
 import androidx.appcompat.widget.Toolbar
 import androidx.coordinatorlayout.widget.CoordinatorLayout
 import androidx.core.view.ViewCompat
 import androidx.core.view.ViewGroupCompat
 import androidx.core.view.WindowInsetsCompat
+import androidx.core.view.animation.PathInterpolatorCompat
 import androidx.core.view.updateLayoutParams
 import androidx.core.view.updatePadding
 import androidx.core.widget.NestedScrollView
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
 import androidx.navigation.findNavController
+import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
 import com.example.android.motion.R
 import com.google.android.material.appbar.CollapsingToolbarLayout
@@ -44,6 +48,8 @@ class CheeseArticleFragment : Fragment() {
 
     companion object {
         const val TRANSITION_NAME_BACKGROUND = "background"
+
+        private val GestureInterpolator = PathInterpolatorCompat.create(0f, 0f, 0f, 1f)
     }
 
     private val args: CheeseArticleFragmentArgs by navArgs()
@@ -111,5 +117,55 @@ class CheeseArticleFragment : Fragment() {
         toolbar.setNavigationOnClickListener { v ->
             v.findNavController().popBackStack()
         }
+
+        val predictiveBackMargin = resources.getDimensionPixelSize(R.dimen.predictive_back_margin)
+        var initialTouchY = -1f
+        requireActivity().onBackPressedDispatcher.addCallback(
+            viewLifecycleOwner,
+            object : OnBackPressedCallback(true) {
+                override fun handleOnBackPressed() {
+                    // This invokes the sharedElementReturnTransition, which is
+                    // MaterialContainerTransform.
+                    findNavController().popBackStack()
+                }
+
+                override fun handleOnBackProgressed(backEvent: BackEventCompat) {
+                    val progress = GestureInterpolator.getInterpolation(backEvent.progress)
+                    if (initialTouchY < 0f) {
+                        initialTouchY = backEvent.touchY
+                    }
+                    val progressY = GestureInterpolator.getInterpolation(
+                        (backEvent.touchY - initialTouchY) / background.height
+                    )
+
+                    // See the motion spec about the calculations below.
+                    // https://developer.android.com/design/ui/mobile/guides/patterns/predictive-back#motion-specs
+
+                    // Shift horizontally.
+                    val maxTranslationX = (background.width / 20) - predictiveBackMargin
+                    background.translationX = progress * maxTranslationX *
+                        (if (backEvent.swipeEdge == BackEventCompat.EDGE_LEFT) 1 else -1)
+
+                    // Shift vertically.
+                    val maxTranslationY = (background.height / 20) - predictiveBackMargin
+                    background.translationY = progressY * maxTranslationY
+
+                    // Scale down from 100% to 90%.
+                    val scale = 1f - (0.1f * progress)
+                    background.scaleX = scale
+                    background.scaleY = scale
+                }
+
+                override fun handleOnBackCancelled() {
+                    initialTouchY = -1f
+                    background.run {
+                        translationX = 0f
+                        translationY = 0f
+                        scaleX = 1f
+                        scaleY = 1f
+                    }
+                }
+            }
+        )
     }
 }

Motion/app/src/main/java/com/example/android/motion/demo/sharedelement/MirrorView.kt

@@ -47,7 +47,7 @@ class MirrorView @JvmOverloads constructor(
             setWillNotDraw(value == null)
         }
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         _substance?.draw(canvas)
     }
 }

Motion/app/src/main/res/values/dimens.xml

@@ -21,4 +21,5 @@
     <dimen name="pick_up_elevation">8dp</dimen>
     <dimen name="fab_elevation">6dp</dimen>
     <dimen name="icon_size">24dp</dimen>
+    <dimen name="predictive_back_margin">8dp</dimen>
 </resources>

Motion/build.gradle

@@ -15,14 +15,14 @@
  */
 
 buildscript {
-    ext.kotlin_version = '1.6.21'
-    ext.navigation_version = '2.4.2'
+    ext.kotlin_version = '1.9.22'
+    ext.navigation_version = '2.7.7'
     repositories {
         google()
         mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:7.3.0'
+        classpath 'com.android.tools.build:gradle:8.2.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$navigation_version"
     }

Motion/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Wed Oct 28 16:25:10 JST 2020
+#Fri Feb 16 14:02:28 JST 2024
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.2-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.4-all.zip