[Predictive Back] Add a new Predictive Back Samples folder.

gradle/libs.versions.toml

@@ -49,7 +49,8 @@ androidx-activity = "androidx.activity:activity:1.7.2"
 androidx-core = "androidx.core:core-ktx:1.10.1"
 androidx-appcompat = "androidx.appcompat:appcompat:1.6.1"
 androidx-exifinterface = "androidx.exifinterface:exifinterface:1.3.6"
-androidx-fragment = "androidx.fragment:fragment-ktx:1.6.0"
+# Fragment 1.7.0 alpha is for predictive back to work with Fragment transitions
+androidx-fragment = "androidx.fragment:fragment-ktx:1.7.0-alpha04"
 androidx-activity-compose = "androidx.activity:activity-compose:1.7.2"
 androidx-navigation-fragment = { module = "androidx.navigation:navigation-fragment", version.ref = "androidx-navigation" }
 androidx-navigation-compose = { module = "androidx.navigation:navigation-compose", version.ref = "androidx-navigation" }

samples/README.md

@@ -80,6 +80,7 @@ Select images/videos in a privacy-friendly way using the photo picker
 Basic usage of Picture-in-Picture mode showcasing a stopwatch
 - [Picture in Picture (PiP) - Video playback](user-interface/picture-in-picture/src/main/java/com/example/android/pip/PiPMovieActivity.kt):
 Basic usage of Picture-in-Picture mode showcasing video playback
+- [Predictive Back](user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBHostingActivity.kt):
 - [Quick Settings](user-interface/quicksettings/src/main/java/com/example/platform/ui/quicksettings/QuickSettings.kt):
 Add your custom tile to the Quick Settings.
 - [Scan with BLE Intent](connectivity/bluetooth/ble/src/main/java/com/example/platform/connectivity/bluetooth/ble/BLEScanIntentSample.kt):

samples/user-interface/predictiveback/README.md

@@ -0,0 +1,9 @@
+# PredictiveBackSample samples
+
+Shows different types of predictive back animations, including:
+
++ back-to-home
++ cross-activity
++ (coming soon) cross-fragment
++ (coming soon) androidx-transitions
++ (coming soon) custom cross-activity

samples/user-interface/predictiveback/build.gradle.kts

@@ -0,0 +1,36 @@
+
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+plugins {
+    id("com.example.platform.sample")
+    alias(libs.plugins.kotlin.android)
+}
+
+android {
+    namespace = "com.example.platform.ui.predictiveback"
+    buildFeatures {
+        viewBinding = true
+    }
+}
+
+dependencies {
+    implementation(libs.androidx.appcompat)
+    implementation(libs.androidx.constraintlayout)
+    implementation(libs.mdc)
+    // Add samples specific dependencies
+}

samples/user-interface/predictiveback/src/main/AndroidManifest.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <application>
+        <activity
+            android:name=".PBHostingActivity"
+            android:exported="false"
+            android:label="@string/title_activity_predictive_back_sample"
+            android:theme="@style/Theme.PlatformSamples" />
+    </application>
+
+</manifest>

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBAnimation.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+class PBAnimation(val title: String, val description: String)
+
+val pbAnimations = mutableListOf<PBAnimation>().apply {
+    add(
+        PBAnimation(
+            "Enable System Animations",
+            "The system animations are back-to-home and default cross-activity. To see them: (1) Enable gesture navigation. (2) In Android 14, enable the Predictive Back Developer Option."
+        )
+    )
+    add(
+        PBAnimation(
+            "Back-to-Home",
+            "To see the back-to-home animation, go to the root activity and swipe back from either the left or right edge to exit the app."
+        )
+    )
+    add(
+        PBAnimation(
+            "Default Cross-Activity",
+            "To see the default cross-activity animation in this app, on this screen swipe back from either the left or right edge."
+        )
+    )
+    add(
+        PBAnimation(
+            "Cross-Fragment",
+            "Animation example coming soon."
+        )
+    )
+}

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBHolder.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+import androidx.recyclerview.widget.RecyclerView
+import com.example.platform.ui.predictiveback.databinding.ListItemAnimationBinding
+
+class PBHolder(
+    private val binding: ListItemAnimationBinding
+) : RecyclerView.ViewHolder(binding.root) {
+    fun bind(animation: PBAnimation) {
+        binding.animationTitle.text = animation.title
+        binding.animationDescription.text = animation.description
+    }
+}

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBHostingActivity.kt

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import com.example.platform.ui.predictiveback.databinding.HostingActivityBinding
+import com.google.android.catalog.framework.annotations.Sample
+
+@Sample(
+    name="Predictive Back Sample",
+    description="Shows Predictive Back animations."
+)
+class PBHostingActivity : AppCompatActivity() {
+
+    private lateinit var binding: HostingActivityBinding
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        binding = HostingActivityBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+    }
+}

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBListAdapter.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import androidx.recyclerview.widget.RecyclerView
+import com.example.platform.ui.predictiveback.databinding.ListItemAnimationBinding
+
+class PBListAdapter(private val animations: List<PBAnimation>) : RecyclerView.Adapter<PBHolder>() {
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PBHolder {
+        val inflater = LayoutInflater.from(parent.context)
+        val binding = ListItemAnimationBinding.inflate(inflater, parent, false)
+        return PBHolder(binding)
+    }
+
+    override fun getItemCount() = animations.size
+
+    override fun onBindViewHolder(holder: PBHolder, position: Int) {
+        val animation = animations[position]
+        holder.bind(animation)
+    }
+}

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBListFragment.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+import android.os.Bundle
+import androidx.fragment.app.Fragment
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.viewModels
+import androidx.recyclerview.widget.LinearLayoutManager
+import com.example.platform.ui.predictiveback.databinding.FragmentAnimationListBinding
+
+class PBListFragment : Fragment() {
+
+    private var _binding: FragmentAnimationListBinding? = null
+    private val binding
+        get() = checkNotNull(_binding){
+            "Cannot access binding in PBListFragment because it is null."
+        }
+
+    private val pbViewModel: PBViewModel by viewModels()
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?,
+    ): View {
+        _binding = FragmentAnimationListBinding.inflate(inflater, container, false)
+        binding.pbRecyclerView.layoutManager = LinearLayoutManager(context)
+
+        val animations = pbViewModel.animations
+        val adapter = PBListAdapter(animations)
+        binding.pbRecyclerView.adapter = adapter
+
+        return binding.root
+    }
+
+    override fun onDestroyView() {
+        super.onDestroyView()
+        _binding = null
+    }
+}

samples/user-interface/predictiveback/src/main/java/com/example/platform/ui/predictiveback/PBViewModel.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.platform.ui.predictiveback
+
+import androidx.lifecycle.ViewModel
+
+class PBViewModel: ViewModel() {
+
+    val animations = pbAnimations
+
+}

samples/user-interface/predictiveback/src/main/res/layout/fragment_animation_list.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  ~ Copyright 2023 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~     https://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <TextView
+        android:id="@+id/textView"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="80dp"
+        android:layout_margin="16dp"
+        android:gravity="center"
+        android:text="@string/predictive_back_sample_first_activity_header"
+        android:textSize="24sp"
+        android:textAppearance="?attr/textAppearanceTitleMedium" />
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:id="@+id/pb_recycler_view" />
+
+</LinearLayout>

samples/user-interface/predictiveback/src/main/res/layout/hosting_activity.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright 2023 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~     https://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<androidx.fragment.app.FragmentContainerView
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/fragment_container"
+    android:name="com.example.platform.ui.predictiveback.PBListFragment"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".PBHostingActivity" />