Merge "Implement fallback recents activity for Go" into ub-launcher3-master
diff --git a/go/quickstep/res/layout/fallback_recents_activity.xml b/go/quickstep/res/layout/fallback_recents_activity.xml
new file mode 100644
index 0000000..653f463
--- /dev/null
+++ b/go/quickstep/res/layout/fallback_recents_activity.xml
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+     Copyright (C) 2019 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
+
+          http://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.
+-->
+<com.android.quickstep.fallback.GoRecentsActivityRootView
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/drag_layer"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:fitsSystemWindows="true">
+
+    <include
+        android:id="@+id/overview_panel"
+        layout="@layout/overview_panel"
+        android:clipChildren="false"
+        android:clipToPadding="false"
+        android:outlineProvider="none"
+        android:theme="@style/HomeScreenElementTheme" />
+</com.android.quickstep.fallback.GoRecentsActivityRootView>
diff --git a/go/quickstep/src/com/android/quickstep/RecentsActivity.java b/go/quickstep/src/com/android/quickstep/RecentsActivity.java
new file mode 100644
index 0000000..a186aaa
--- /dev/null
+++ b/go/quickstep/src/com/android/quickstep/RecentsActivity.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2019 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
+ *
+ *      http://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.android.quickstep;
+
+import android.app.ActivityOptions;
+import android.view.View;
+
+import com.android.launcher3.R;
+import com.android.launcher3.views.BaseDragLayer;
+import com.android.quickstep.fallback.GoRecentsActivityRootView;
+import com.android.quickstep.views.IconRecentsView;
+
+/**
+ * A recents activity that displays recent tasks with an icon and small snapshot.
+ */
+public final class RecentsActivity extends BaseRecentsActivity {
+
+    private GoRecentsActivityRootView mRecentsRootView;
+    private IconRecentsView mIconRecentsView;
+
+    @Override
+    protected void initViews() {
+        setContentView(R.layout.fallback_recents_activity);
+        mRecentsRootView = findViewById(R.id.drag_layer);
+        mIconRecentsView = findViewById(R.id.overview_panel);
+    }
+
+    @Override
+    protected void reapplyUi() {
+        //TODO: Implement this depending on how insets will affect the view.
+    }
+
+    @Override
+    public BaseDragLayer getDragLayer() {
+        return mRecentsRootView;
+    }
+
+    @Override
+    public View getRootView() {
+        return mRecentsRootView;
+    }
+
+    @Override
+    public <T extends View> T getOverviewPanel() {
+        return (T) mIconRecentsView;
+    }
+
+    @Override
+    public ActivityOptions getActivityLaunchOptions(View v) {
+        //TODO: Hook into recents launch animation
+        return null;
+    }
+
+    @Override
+    protected void onStart() {
+        // Set the alpha to 1 before calling super, as it may get set back to 0 due to
+        // onActivityStart callback.
+        mIconRecentsView.setAlpha(0);
+        super.onStart();
+    }
+}
diff --git a/go/quickstep/src/com/android/quickstep/fallback/GoRecentsActivityRootView.java b/go/quickstep/src/com/android/quickstep/fallback/GoRecentsActivityRootView.java
new file mode 100644
index 0000000..d748e89
--- /dev/null
+++ b/go/quickstep/src/com/android/quickstep/fallback/GoRecentsActivityRootView.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2019 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
+ *
+ *      http://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.android.quickstep.fallback;
+
+import android.content.Context;
+import android.util.AttributeSet;
+
+import com.android.launcher3.views.BaseDragLayer;
+import com.android.quickstep.RecentsActivity;
+
+/**
+ * Minimal implementation of {@link BaseDragLayer} for Go's fallback recents activity.
+ */
+public final class GoRecentsActivityRootView extends BaseDragLayer<RecentsActivity> {
+    public GoRecentsActivityRootView(Context context, AttributeSet attrs) {
+        super(context, attrs, 1 /* alphaChannelCount */);
+    }
+}
diff --git a/quickstep/res/layout/fallback_recents_activity.xml b/quickstep/recents_ui_overrides/res/layout/fallback_recents_activity.xml
similarity index 100%
rename from quickstep/res/layout/fallback_recents_activity.xml
rename to quickstep/recents_ui_overrides/res/layout/fallback_recents_activity.xml
diff --git a/quickstep/src/com/android/quickstep/RecentsActivity.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/RecentsActivity.java
similarity index 63%
rename from quickstep/src/com/android/quickstep/RecentsActivity.java
rename to quickstep/recents_ui_overrides/src/com/android/quickstep/RecentsActivity.java
index b76a1ab..8d7039e 100644
--- a/quickstep/src/com/android/quickstep/RecentsActivity.java
+++ b/quickstep/recents_ui_overrides/src/com/android/quickstep/RecentsActivity.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017 The Android Open Source Project
+ * Copyright (C) 2019 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.
@@ -15,12 +15,11 @@
  */
 package com.android.quickstep;
 
-import static android.content.pm.ActivityInfo.CONFIG_ORIENTATION;
-import static android.content.pm.ActivityInfo.CONFIG_SCREEN_SIZE;
-
 import static com.android.launcher3.QuickstepAppTransitionManagerImpl.RECENTS_LAUNCH_DURATION;
-import static com.android.launcher3.QuickstepAppTransitionManagerImpl.STATUS_BAR_TRANSITION_DURATION;
-import static com.android.launcher3.QuickstepAppTransitionManagerImpl.STATUS_BAR_TRANSITION_PRE_DELAY;
+import static com.android.launcher3.QuickstepAppTransitionManagerImpl
+        .STATUS_BAR_TRANSITION_DURATION;
+import static com.android.launcher3.QuickstepAppTransitionManagerImpl
+        .STATUS_BAR_TRANSITION_PRE_DELAY;
 import static com.android.quickstep.TaskUtils.getRecentsWindowAnimator;
 import static com.android.quickstep.TaskUtils.taskIsATargetWithMode;
 import static com.android.systemui.shared.system.RemoteAnimationTargetCompat.MODE_CLOSING;
@@ -29,23 +28,16 @@
 import android.animation.AnimatorListenerAdapter;
 import android.animation.AnimatorSet;
 import android.app.ActivityOptions;
-import android.content.Intent;
 import android.content.res.Configuration;
-import android.os.Bundle;
 import android.os.Handler;
 import android.os.Looper;
 import android.view.View;
 
-import com.android.launcher3.AbstractFloatingView;
-import com.android.launcher3.BaseDraggingActivity;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.InvariantDeviceProfile;
 import com.android.launcher3.LauncherAnimationRunner;
 import com.android.launcher3.R;
 import com.android.launcher3.anim.Interpolators;
-import com.android.launcher3.uioverrides.UiFactory;
-import com.android.launcher3.util.SystemUiController;
-import com.android.launcher3.util.Themes;
 import com.android.launcher3.views.BaseDragLayer;
 import com.android.quickstep.fallback.FallbackRecentsView;
 import com.android.quickstep.fallback.RecentsRootView;
@@ -56,46 +48,22 @@
 import com.android.systemui.shared.system.RemoteAnimationRunnerCompat;
 import com.android.systemui.shared.system.RemoteAnimationTargetCompat;
 
-import java.io.FileDescriptor;
-import java.io.PrintWriter;
-
 /**
- * A simple activity to show the recently launched tasks
+ * A recents activity that shows the recently launched tasks as swipable task cards.
+ * See {@link com.android.quickstep.views.RecentsView}.
  */
-public class RecentsActivity extends BaseDraggingActivity {
+public final class RecentsActivity extends BaseRecentsActivity {
 
     private Handler mUiHandler = new Handler(Looper.getMainLooper());
     private RecentsRootView mRecentsRootView;
     private FallbackRecentsView mFallbackRecentsView;
 
-    private Configuration mOldConfig;
-
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-
-        mOldConfig = new Configuration(getResources().getConfiguration());
-        initDeviceProfile();
-
+    protected void initViews() {
         setContentView(R.layout.fallback_recents_activity);
         mRecentsRootView = findViewById(R.id.drag_layer);
         mFallbackRecentsView = findViewById(R.id.overview_panel);
-
         mRecentsRootView.setup();
-
-        getSystemUiController().updateUiState(SystemUiController.UI_STATE_BASE_WINDOW,
-                Themes.getAttrBoolean(this, R.attr.isWorkspaceDarkText));
-        RecentsActivityTracker.onRecentsActivityCreate(this);
-    }
-
-    @Override
-    public void onConfigurationChanged(Configuration newConfig) {
-        int diff = newConfig.diff(mOldConfig);
-        if ((diff & (CONFIG_ORIENTATION | CONFIG_SCREEN_SIZE)) != 0) {
-            onHandleConfigChanged();
-        }
-        mOldConfig.setTo(newConfig);
-        super.onConfigurationChanged(newConfig);
     }
 
     @Override
@@ -110,16 +78,10 @@
         }
     }
 
-    private void onHandleConfigChanged() {
-        mUserEventDispatcher = null;
-        initDeviceProfile();
-
-        AbstractFloatingView.closeOpenViews(this, true,
-                AbstractFloatingView.TYPE_ALL & ~AbstractFloatingView.TYPE_REBIND_SAFE);
-        dispatchDeviceProfileChanged();
-
+    @Override
+    protected void onHandleConfigChanged() {
+        super.onHandleConfigChanged();
         mRecentsRootView.setup();
-        reapplyUi();
     }
 
     @Override
@@ -127,15 +89,12 @@
         mRecentsRootView.dispatchInsets();
     }
 
-    private void initDeviceProfile() {
+    @Override
+    protected DeviceProfile createDeviceProfile() {
         DeviceProfile dp = InvariantDeviceProfile.INSTANCE.get(this).getDeviceProfile(this);
-
-        // In case we are reusing IDP, create a copy so that we don't conflict with Launcher
-        // activity.
-        mDeviceProfile = (mRecentsRootView != null) && isInMultiWindowMode()
+        return (mRecentsRootView != null) && isInMultiWindowMode()
                 ? dp.getMultiWindowProfile(this, mRecentsRootView.getLastKnownSize())
-                : dp.copy(this);
-        onDeviceProfileInitiated();
+                : super.createDeviceProfile();
     }
 
     @Override
@@ -211,55 +170,4 @@
         super.onStart();
         mFallbackRecentsView.resetTaskVisuals();
     }
-
-    @Override
-    protected void onStop() {
-        super.onStop();
-
-        // Workaround for b/78520668, explicitly trim memory once UI is hidden
-        onTrimMemory(TRIM_MEMORY_UI_HIDDEN);
-    }
-
-    @Override
-    public void onEnterAnimationComplete() {
-        super.onEnterAnimationComplete();
-        UiFactory.onEnterAnimationComplete(this);
-    }
-
-    @Override
-    public void onTrimMemory(int level) {
-        super.onTrimMemory(level);
-        UiFactory.onTrimMemory(this, level);
-    }
-
-    @Override
-    protected void onNewIntent(Intent intent) {
-        super.onNewIntent(intent);
-        RecentsActivityTracker.onRecentsActivityNewIntent(this);
-    }
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        RecentsActivityTracker.onRecentsActivityDestroy(this);
-    }
-
-    @Override
-    public void onBackPressed() {
-        // TODO: Launch the task we came from
-        startHome();
-    }
-
-    public void startHome() {
-        startActivity(new Intent(Intent.ACTION_MAIN)
-                .addCategory(Intent.CATEGORY_HOME)
-                .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
-    }
-
-    @Override
-    public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
-        super.dump(prefix, fd, writer, args);
-        writer.println(prefix + "Misc:");
-        dumpMisc(writer);
-    }
 }
diff --git a/quickstep/src/com/android/quickstep/fallback/FallbackRecentsView.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/FallbackRecentsView.java
similarity index 100%
rename from quickstep/src/com/android/quickstep/fallback/FallbackRecentsView.java
rename to quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/FallbackRecentsView.java
diff --git a/quickstep/src/com/android/quickstep/fallback/RecentsRootView.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/RecentsRootView.java
similarity index 100%
rename from quickstep/src/com/android/quickstep/fallback/RecentsRootView.java
rename to quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/RecentsRootView.java
diff --git a/quickstep/src/com/android/quickstep/fallback/RecentsTaskController.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/RecentsTaskController.java
similarity index 100%
rename from quickstep/src/com/android/quickstep/fallback/RecentsTaskController.java
rename to quickstep/recents_ui_overrides/src/com/android/quickstep/fallback/RecentsTaskController.java
diff --git a/quickstep/src/com/android/quickstep/BaseRecentsActivity.java b/quickstep/src/com/android/quickstep/BaseRecentsActivity.java
new file mode 100644
index 0000000..c840132
--- /dev/null
+++ b/quickstep/src/com/android/quickstep/BaseRecentsActivity.java
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2019 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
+ *
+ *      http://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.android.quickstep;
+
+import static android.content.pm.ActivityInfo.CONFIG_ORIENTATION;
+import static android.content.pm.ActivityInfo.CONFIG_SCREEN_SIZE;
+
+import android.content.Intent;
+import android.content.res.Configuration;
+import android.os.Bundle;
+
+import com.android.launcher3.AbstractFloatingView;
+import com.android.launcher3.BaseDraggingActivity;
+import com.android.launcher3.DeviceProfile;
+import com.android.launcher3.InvariantDeviceProfile;
+import com.android.launcher3.R;
+import com.android.launcher3.uioverrides.UiFactory;
+import com.android.launcher3.util.SystemUiController;
+import com.android.launcher3.util.Themes;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+
+/**
+ * A base fallback recents activity that provides support for device profile changes, activity
+ * lifecycle tracking, and basic input handling from recents.
+ *
+ * This class is only used as a fallback in case the default launcher does not have a recents
+ * implementation.
+ */
+public abstract class BaseRecentsActivity extends BaseDraggingActivity {
+
+    private Configuration mOldConfig;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        mOldConfig = new Configuration(getResources().getConfiguration());
+        initDeviceProfile();
+        initViews();
+
+        getSystemUiController().updateUiState(SystemUiController.UI_STATE_BASE_WINDOW,
+                Themes.getAttrBoolean(this, R.attr.isWorkspaceDarkText));
+        RecentsActivityTracker.onRecentsActivityCreate(this);
+    }
+
+    /**
+     * Init drag layer and overview panel views.
+     */
+    abstract protected void initViews();
+
+    @Override
+    public void onConfigurationChanged(Configuration newConfig) {
+        int diff = newConfig.diff(mOldConfig);
+        if ((diff & (CONFIG_ORIENTATION | CONFIG_SCREEN_SIZE)) != 0) {
+            onHandleConfigChanged();
+        }
+        mOldConfig.setTo(newConfig);
+        super.onConfigurationChanged(newConfig);
+    }
+
+    /**
+     * Logic for when device configuration changes (rotation, screen size change, multi-window,
+     * etc.)
+     */
+    protected void onHandleConfigChanged() {
+        mUserEventDispatcher = null;
+        initDeviceProfile();
+
+        AbstractFloatingView.closeOpenViews(this, true,
+                AbstractFloatingView.TYPE_ALL & ~AbstractFloatingView.TYPE_REBIND_SAFE);
+        dispatchDeviceProfileChanged();
+
+        reapplyUi();
+    }
+
+    /**
+     * Initialize/update the device profile.
+     */
+    private void initDeviceProfile() {
+        mDeviceProfile = createDeviceProfile();
+        onDeviceProfileInitiated();
+    }
+
+    /**
+     * Generate the device profile to use in this activity.
+     * @return device profile
+     */
+    protected DeviceProfile createDeviceProfile() {
+        DeviceProfile dp = InvariantDeviceProfile.INSTANCE.get(this).getDeviceProfile(this);
+
+        // In case we are reusing IDP, create a copy so that we don't conflict with Launcher
+        // activity.
+        return dp.copy(this);
+    }
+
+
+    @Override
+    protected void onStop() {
+        super.onStop();
+
+        // Workaround for b/78520668, explicitly trim memory once UI is hidden
+        onTrimMemory(TRIM_MEMORY_UI_HIDDEN);
+    }
+
+    @Override
+    public void onEnterAnimationComplete() {
+        super.onEnterAnimationComplete();
+        UiFactory.onEnterAnimationComplete(this);
+    }
+
+    @Override
+    public void onTrimMemory(int level) {
+        super.onTrimMemory(level);
+        UiFactory.onTrimMemory(this, level);
+    }
+
+    @Override
+    protected void onNewIntent(Intent intent) {
+        super.onNewIntent(intent);
+        RecentsActivityTracker.onRecentsActivityNewIntent(this);
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        RecentsActivityTracker.onRecentsActivityDestroy(this);
+    }
+
+    @Override
+    public void onBackPressed() {
+        // TODO: Launch the task we came from
+        startHome();
+    }
+
+    public void startHome() {
+        startActivity(new Intent(Intent.ACTION_MAIN)
+                .addCategory(Intent.CATEGORY_HOME)
+                .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
+    }
+
+    @Override
+    public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
+        super.dump(prefix, fd, writer, args);
+        writer.println(prefix + "Misc:");
+        dumpMisc(writer);
+    }
+}
diff --git a/quickstep/src/com/android/quickstep/RecentsActivityTracker.java b/quickstep/src/com/android/quickstep/RecentsActivityTracker.java
index fb6090e..0822e61 100644
--- a/quickstep/src/com/android/quickstep/RecentsActivityTracker.java
+++ b/quickstep/src/com/android/quickstep/RecentsActivityTracker.java
@@ -30,17 +30,18 @@
 import java.util.function.BiPredicate;
 
 /**
- * Utility class to track create/destroy for RecentsActivity
+ * Utility class to track create/destroy for some {@link BaseRecentsActivity}.
  */
 @TargetApi(Build.VERSION_CODES.P)
-public class RecentsActivityTracker implements ActivityInitListener {
+public class RecentsActivityTracker<T extends BaseRecentsActivity> implements ActivityInitListener {
 
-    private static WeakReference<RecentsActivity> sCurrentActivity = new WeakReference<>(null);
+    private static WeakReference<BaseRecentsActivity> sCurrentActivity =
+            new WeakReference<>(null);
     private static final Scheduler sScheduler = new Scheduler();
 
-    private final BiPredicate<RecentsActivity, Boolean> mOnInitListener;
+    private final BiPredicate<T, Boolean> mOnInitListener;
 
-    public RecentsActivityTracker(BiPredicate<RecentsActivity, Boolean> onInitListener) {
+    public RecentsActivityTracker(BiPredicate<T, Boolean> onInitListener) {
         mOnInitListener = onInitListener;
     }
 
@@ -54,12 +55,12 @@
         sScheduler.clearReference(this);
     }
 
-    private boolean init(RecentsActivity activity, boolean visible) {
+    private boolean init(T activity, boolean visible) {
         return mOnInitListener.test(activity, visible);
     }
 
-    public static RecentsActivity getCurrentActivity() {
-        return sCurrentActivity.get();
+    public static <T extends BaseRecentsActivity> T getCurrentActivity() {
+        return (T) sCurrentActivity.get();
     }
 
     @Override
@@ -71,17 +72,17 @@
         context.startActivity(intent, options);
     }
 
-    public static void onRecentsActivityCreate(RecentsActivity activity) {
+    public static void onRecentsActivityCreate(BaseRecentsActivity activity) {
         sCurrentActivity = new WeakReference<>(activity);
         sScheduler.initIfPending(activity, false);
     }
 
 
-    public static void onRecentsActivityNewIntent(RecentsActivity activity) {
+    public static void onRecentsActivityNewIntent(BaseRecentsActivity activity) {
         sScheduler.initIfPending(activity, activity.isStarted());
     }
 
-    public static void onRecentsActivityDestroy(RecentsActivity activity) {
+    public static void onRecentsActivityDestroy(BaseRecentsActivity activity) {
         if (sCurrentActivity.get() == activity) {
             sCurrentActivity.clear();
         }
@@ -103,13 +104,14 @@
 
         @Override
         public void run() {
-            RecentsActivity activity = sCurrentActivity.get();
+            BaseRecentsActivity activity = sCurrentActivity.get();
             if (activity != null) {
                 initIfPending(activity, activity.isStarted());
             }
         }
 
-        public synchronized boolean initIfPending(RecentsActivity activity, boolean alreadyOnHome) {
+        public synchronized boolean initIfPending(BaseRecentsActivity activity,
+                boolean alreadyOnHome) {
             RecentsActivityTracker tracker = mPendingTracker.get();
             if (tracker != null) {
                 if (!tracker.init(activity, alreadyOnHome)) {