Using a proxy activity for startActivityForResult

This ensures that the home task is never blocked by a different task

Bug: 74500048
Change-Id: I01fd26f1d6242e39b2d8fabac5e064b748aebe62

quickstep/src/com/android/launcher3/proxy/ProxyActivityStarter.java

@@ -0,0 +1,82 @@
+/*
+ * 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.launcher3.proxy;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentSender.SendIntentException;
+import android.os.Bundle;
+import android.util.Log;
+
+public class ProxyActivityStarter extends Activity {
+
+    private static final String TAG = "ProxyActivityStarter";
+
+    public static final String EXTRA_PARAMS = "start-activity-params";
+
+    private StartActivityParams mParams;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setVisible(false);
+
+        mParams = getIntent().getParcelableExtra(EXTRA_PARAMS);
+        if (mParams == null) {
+            Log.d(TAG, "Proxy activity started without params");
+            finishAndRemoveTask();
+            return;
+        }
+
+        if (savedInstanceState != null) {
+            // Already started the activity. Just wait for the result.
+            return;
+        }
+
+        if (mParams.intent != null) {
+            startActivityForResult(mParams.intent, mParams.requestCode, mParams.options);
+            return;
+        } else if (mParams.intentSender != null) {
+            try {
+                startIntentSenderForResult(mParams.intentSender, mParams.requestCode,
+                        mParams.fillInIntent, mParams.flagsMask, mParams.flagsValues,
+                        mParams.extraFlags,
+                        mParams.options);
+                return;
+            } catch (SendIntentException e) {
+                mParams.deliverResult(this, RESULT_CANCELED, null);
+            }
+        }
+        finishAndRemoveTask();
+    }
+
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+        if (requestCode == mParams.requestCode) {
+            mParams.deliverResult(this, resultCode, data);
+        }
+        finishAndRemoveTask();
+    }
+
+    public static Intent getLaunchIntent(Context context, StartActivityParams params) {
+        return new Intent(context, ProxyActivityStarter.class)
+                .putExtra(EXTRA_PARAMS, params)
+                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED
+                        | Intent.FLAG_ACTIVITY_CLEAR_TASK);
+    }
+}

quickstep/src/com/android/launcher3/proxy/StartActivityParams.java

@@ -0,0 +1,103 @@
+/*
+ * 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.launcher3.proxy;
+
+import android.app.Activity;
+import android.app.PendingIntent;
+import android.app.PendingIntent.CanceledException;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentSender;
+import android.os.Bundle;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.util.Log;
+
+public class StartActivityParams implements Parcelable {
+
+    private static final String TAG = "StartActivityParams";
+
+    private final PendingIntent mCallback;
+    public final int requestCode;
+
+    public Intent intent;
+
+    public IntentSender intentSender;
+    public Intent fillInIntent;
+    public int flagsMask;
+    public int flagsValues;
+    public int extraFlags;
+    public Bundle options;
+
+    public StartActivityParams(Activity activity, int requestCode) {
+        mCallback = activity.createPendingResult(requestCode, new Intent(),
+                PendingIntent.FLAG_ONE_SHOT | PendingIntent.FLAG_UPDATE_CURRENT);
+        this.requestCode = requestCode;
+    }
+
+    private StartActivityParams(Parcel parcel) {
+        mCallback = parcel.readTypedObject(PendingIntent.CREATOR);
+        requestCode = parcel.readInt();
+        intent = parcel.readTypedObject(Intent.CREATOR);
+
+        intentSender = parcel.readTypedObject(IntentSender.CREATOR);
+        fillInIntent = parcel.readTypedObject(Intent.CREATOR);
+        flagsMask = parcel.readInt();
+        flagsValues = parcel.readInt();
+        extraFlags = parcel.readInt();
+        options = parcel.readBundle();
+    }
+
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel parcel, int flags) {
+        parcel.writeTypedObject(mCallback, flags);
+        parcel.writeInt(requestCode);
+        parcel.writeTypedObject(intent, flags);
+
+        parcel.writeTypedObject(intentSender, flags);
+        parcel.writeTypedObject(fillInIntent, flags);
+        parcel.writeInt(flagsMask);
+        parcel.writeInt(flagsValues);
+        parcel.writeInt(extraFlags);
+        parcel.writeBundle(options);
+    }
+
+    public void deliverResult(Context context, int resultCode, Intent data) {
+        try {
+            mCallback.send(context, resultCode, data);
+        } catch (CanceledException e) {
+            Log.e(TAG, "Unable to send back result", e);
+        }
+    }
+
+    public static final Parcelable.Creator<StartActivityParams> CREATOR =
+            new Parcelable.Creator<StartActivityParams>() {
+                public StartActivityParams createFromParcel(Parcel source) {
+                    return new StartActivityParams(source);
+                }
+
+                public StartActivityParams[] newArray(int size) {
+                    return new StartActivityParams[size];
+                }
+            };
+}

quickstep/src/com/android/launcher3/uioverrides/UiFactory.java

@@ -16,6 +16,8 @@
 
 package com.android.launcher3.uioverrides;
 
+import static android.app.Activity.RESULT_CANCELED;
+
 import static com.android.launcher3.AbstractFloatingView.TYPE_ALL;
 import static com.android.launcher3.AbstractFloatingView.TYPE_HIDE_BACK_BUTTON;
 import static com.android.launcher3.LauncherState.ALL_APPS;
@@ -31,6 +33,9 @@ import android.animation.AnimatorSet;
 import android.animation.ValueAnimator;
 import android.app.Activity;
 import android.content.Context;
+import android.content.Intent;
+import android.content.IntentSender;
+import android.os.Bundle;
 import android.os.CancellationSignal;
 import android.util.Base64;
 
@@ -43,6 +48,8 @@ import com.android.launcher3.LauncherStateManager.StateHandler;
 import com.android.launcher3.QuickstepAppTransitionManagerImpl;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.dragndrop.DragLayer;
+import com.android.launcher3.proxy.ProxyActivityStarter;
+import com.android.launcher3.proxy.StartActivityParams;
 import com.android.quickstep.OverviewInteractionState;
 import com.android.quickstep.RecentsModel;
 import com.android.quickstep.SysUINavigationMode;
@@ -192,6 +199,40 @@ public class UiFactory extends RecentsUiFactory {
         return true;
     }
 
+    public static boolean startIntentSenderForResult(Activity activity, IntentSender intent,
+            int requestCode, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags,
+            Bundle options) {
+        StartActivityParams params = new StartActivityParams(activity, requestCode);
+        params.intentSender = intent;
+        params.fillInIntent = fillInIntent;
+        params.flagsMask = flagsMask;
+        params.flagsValues = flagsValues;
+        params.extraFlags = extraFlags;
+        params.options = options;
+        ((Context) activity).startActivity(ProxyActivityStarter.getLaunchIntent(activity, params));
+        return true;
+    }
+
+    public static boolean startActivityForResult(Activity activity, Intent intent, int requestCode,
+            Bundle options) {
+        StartActivityParams params = new StartActivityParams(activity, requestCode);
+        params.intent = intent;
+        params.options = options;
+        activity.startActivity(ProxyActivityStarter.getLaunchIntent(activity, params));
+        return true;
+    }
+
+    /**
+     * Removes any active ProxyActivityStarter task and sends RESULT_CANCELED to Launcher.
+     *
+     * ProxyActivityStarter is started with clear task to reset the task after which it removes the
+     * task itself.
+     */
+    public static void resetPendingActivityResults(Launcher launcher, int requestCode) {
+        launcher.onActivityResult(requestCode, RESULT_CANCELED, null);
+        launcher.startActivity(ProxyActivityStarter.getLaunchIntent(launcher, null));
+    }
+
     public static ScaleAndTranslation getOverviewScaleAndTranslationForNormalState(Launcher l) {
         if (SysUINavigationMode.getMode(l) == Mode.NO_BUTTON) {
             float offscreenTranslationX = l.getDeviceProfile().widthPx