| /* |
| * Copyright (C) 2022 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 android.window; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.os.Bundle; |
| import android.os.Handler; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| import android.os.RemoteException; |
| import android.os.ResultReceiver; |
| import android.util.Log; |
| |
| import java.util.HashMap; |
| |
| /** |
| * A {@link OnBackInvokedDispatcher} for IME that forwards {@link OnBackInvokedCallback} |
| * registrations from the IME process to the app process to be registered on the app window. |
| * <p> |
| * The app process creates and propagates an instance of {@link ImeOnBackInvokedDispatcher} |
| * to the IME to be set on the IME window's {@link WindowOnBackInvokedDispatcher}. |
| * <p> |
| * @see WindowOnBackInvokedDispatcher#setImeOnBackInvokedDispatcher |
| * |
| * @hide |
| */ |
| public class ImeOnBackInvokedDispatcher implements OnBackInvokedDispatcher, Parcelable { |
| |
| private static final String TAG = "ImeBackDispatcher"; |
| static final String RESULT_KEY_ID = "id"; |
| static final String RESULT_KEY_CALLBACK = "callback"; |
| static final String RESULT_KEY_PRIORITY = "priority"; |
| static final int RESULT_CODE_REGISTER = 0; |
| static final int RESULT_CODE_UNREGISTER = 1; |
| @NonNull |
| private final ResultReceiver mResultReceiver; |
| |
| public ImeOnBackInvokedDispatcher(Handler handler) { |
| mResultReceiver = new ResultReceiver(handler) { |
| @Override |
| public void onReceiveResult(int resultCode, Bundle resultData) { |
| WindowOnBackInvokedDispatcher dispatcher = getReceivingDispatcher(); |
| if (dispatcher != null) { |
| receive(resultCode, resultData, dispatcher); |
| } |
| } |
| }; |
| } |
| |
| /** |
| * Override this method to return the {@link WindowOnBackInvokedDispatcher} of the window |
| * that should receive the forwarded callback. |
| */ |
| @Nullable |
| protected WindowOnBackInvokedDispatcher getReceivingDispatcher() { |
| return null; |
| } |
| |
| ImeOnBackInvokedDispatcher(Parcel in) { |
| mResultReceiver = in.readTypedObject(ResultReceiver.CREATOR); |
| } |
| |
| @Override |
| public void registerOnBackInvokedCallback( |
| @OnBackInvokedDispatcher.Priority int priority, |
| @NonNull OnBackInvokedCallback callback) { |
| final Bundle bundle = new Bundle(); |
| final IOnBackInvokedCallback iCallback = |
| new WindowOnBackInvokedDispatcher.OnBackInvokedCallbackWrapper(callback); |
| bundle.putBinder(RESULT_KEY_CALLBACK, iCallback.asBinder()); |
| bundle.putInt(RESULT_KEY_PRIORITY, priority); |
| bundle.putInt(RESULT_KEY_ID, callback.hashCode()); |
| mResultReceiver.send(RESULT_CODE_REGISTER, bundle); |
| } |
| |
| @Override |
| public void unregisterOnBackInvokedCallback( |
| @NonNull OnBackInvokedCallback callback) { |
| Bundle bundle = new Bundle(); |
| bundle.putInt(RESULT_KEY_ID, callback.hashCode()); |
| mResultReceiver.send(RESULT_CODE_UNREGISTER, bundle); |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public void writeToParcel(@NonNull Parcel dest, int flags) { |
| dest.writeTypedObject(mResultReceiver, flags); |
| } |
| |
| @NonNull |
| public static final Parcelable.Creator<ImeOnBackInvokedDispatcher> CREATOR = |
| new Parcelable.Creator<ImeOnBackInvokedDispatcher>() { |
| public ImeOnBackInvokedDispatcher createFromParcel(Parcel in) { |
| return new ImeOnBackInvokedDispatcher(in); |
| } |
| public ImeOnBackInvokedDispatcher[] newArray(int size) { |
| return new ImeOnBackInvokedDispatcher[size]; |
| } |
| }; |
| |
| private final HashMap<Integer, OnBackInvokedCallback> mImeCallbackMap = new HashMap<>(); |
| |
| private void receive( |
| int resultCode, Bundle resultData, |
| @NonNull OnBackInvokedDispatcher receivingDispatcher) { |
| final int callbackId = resultData.getInt(RESULT_KEY_ID); |
| if (resultCode == RESULT_CODE_REGISTER) { |
| int priority = resultData.getInt(RESULT_KEY_PRIORITY); |
| final IOnBackInvokedCallback callback = IOnBackInvokedCallback.Stub.asInterface( |
| resultData.getBinder(RESULT_KEY_CALLBACK)); |
| registerReceivedCallback( |
| callback, priority, callbackId, receivingDispatcher); |
| } else if (resultCode == RESULT_CODE_UNREGISTER) { |
| unregisterReceivedCallback(callbackId, receivingDispatcher); |
| } |
| } |
| |
| private void registerReceivedCallback( |
| @NonNull IOnBackInvokedCallback iCallback, |
| @OnBackInvokedDispatcher.Priority int priority, |
| int callbackId, |
| @NonNull OnBackInvokedDispatcher receivingDispatcher) { |
| final ImeOnBackInvokedCallback imeCallback = |
| new ImeOnBackInvokedCallback(iCallback); |
| mImeCallbackMap.put(callbackId, imeCallback); |
| receivingDispatcher.registerOnBackInvokedCallback(priority, imeCallback); |
| } |
| |
| private void unregisterReceivedCallback( |
| int callbackId, OnBackInvokedDispatcher receivingDispatcher) { |
| final OnBackInvokedCallback callback = mImeCallbackMap.get(callbackId); |
| if (callback == null) { |
| Log.e(TAG, "Ime callback not found. Ignoring unregisterReceivedCallback. " |
| + "callbackId: " + callbackId); |
| return; |
| } |
| receivingDispatcher.unregisterOnBackInvokedCallback(callback); |
| } |
| |
| /** Clears all registered callbacks on the instance. */ |
| public void clear() { |
| // Unregister previously registered callbacks if there's any. |
| if (getReceivingDispatcher() != null) { |
| for (OnBackInvokedCallback callback : mImeCallbackMap.values()) { |
| getReceivingDispatcher().unregisterOnBackInvokedCallback(callback); |
| } |
| } |
| mImeCallbackMap.clear(); |
| } |
| |
| static class ImeOnBackInvokedCallback implements OnBackInvokedCallback { |
| @NonNull |
| private final IOnBackInvokedCallback mIOnBackInvokedCallback; |
| |
| ImeOnBackInvokedCallback(@NonNull IOnBackInvokedCallback iCallback) { |
| mIOnBackInvokedCallback = iCallback; |
| } |
| |
| @Override |
| public void onBackInvoked() { |
| try { |
| if (mIOnBackInvokedCallback != null) { |
| mIOnBackInvokedCallback.onBackInvoked(); |
| } |
| } catch (RemoteException e) { |
| Log.e(TAG, "Exception when invoking forwarded callback. e: ", e); |
| } |
| } |
| |
| IOnBackInvokedCallback getIOnBackInvokedCallback() { |
| return mIOnBackInvokedCallback; |
| } |
| } |
| } |