| /* |
| * Copyright (C) 2010 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.view; |
| |
| import android.os.MessageQueue; |
| import android.util.Slog; |
| |
| /** |
| * An input queue provides a mechanism for an application to receive incoming |
| * input events. Currently only usable from native code. |
| */ |
| public final class InputQueue { |
| private static final String TAG = "InputQueue"; |
| |
| private static final boolean DEBUG = false; |
| |
| /** |
| * Interface to receive notification of when an InputQueue is associated |
| * and dissociated with a thread. |
| */ |
| public static interface Callback { |
| /** |
| * Called when the given InputQueue is now associated with the |
| * thread making this call, so it can start receiving events from it. |
| */ |
| void onInputQueueCreated(InputQueue queue); |
| |
| /** |
| * Called when the given InputQueue is no longer associated with |
| * the thread and thus not dispatching events. |
| */ |
| void onInputQueueDestroyed(InputQueue queue); |
| } |
| |
| final InputChannel mChannel; |
| |
| private static final Object sLock = new Object(); |
| |
| private static native void nativeRegisterInputChannel(InputChannel inputChannel, |
| InputHandler inputHandler, MessageQueue messageQueue); |
| private static native void nativeUnregisterInputChannel(InputChannel inputChannel); |
| private static native void nativeFinished(long finishedToken, boolean handled); |
| |
| /** @hide */ |
| public InputQueue(InputChannel channel) { |
| mChannel = channel; |
| } |
| |
| /** @hide */ |
| public InputChannel getInputChannel() { |
| return mChannel; |
| } |
| |
| /** |
| * Registers an input channel and handler. |
| * @param inputChannel The input channel to register. |
| * @param inputHandler The input handler to input events send to the target. |
| * @param messageQueue The message queue on whose thread the handler should be invoked. |
| * @hide |
| */ |
| public static void registerInputChannel(InputChannel inputChannel, InputHandler inputHandler, |
| MessageQueue messageQueue) { |
| if (inputChannel == null) { |
| throw new IllegalArgumentException("inputChannel must not be null"); |
| } |
| if (inputHandler == null) { |
| throw new IllegalArgumentException("inputHandler must not be null"); |
| } |
| if (messageQueue == null) { |
| throw new IllegalArgumentException("messageQueue must not be null"); |
| } |
| |
| synchronized (sLock) { |
| if (DEBUG) { |
| Slog.d(TAG, "Registering input channel '" + inputChannel + "'"); |
| } |
| |
| nativeRegisterInputChannel(inputChannel, inputHandler, messageQueue); |
| } |
| } |
| |
| /** |
| * Unregisters an input channel. |
| * Does nothing if the channel is not currently registered. |
| * @param inputChannel The input channel to unregister. |
| * @hide |
| */ |
| public static void unregisterInputChannel(InputChannel inputChannel) { |
| if (inputChannel == null) { |
| throw new IllegalArgumentException("inputChannel must not be null"); |
| } |
| |
| synchronized (sLock) { |
| if (DEBUG) { |
| Slog.d(TAG, "Unregistering input channel '" + inputChannel + "'"); |
| } |
| |
| nativeUnregisterInputChannel(inputChannel); |
| } |
| } |
| |
| @SuppressWarnings("unused") |
| private static void dispatchKeyEvent(InputHandler inputHandler, |
| KeyEvent event, long finishedToken) { |
| FinishedCallback finishedCallback = FinishedCallback.obtain(finishedToken); |
| inputHandler.handleKey(event, finishedCallback); |
| } |
| |
| @SuppressWarnings("unused") |
| private static void dispatchMotionEvent(InputHandler inputHandler, |
| MotionEvent event, long finishedToken) { |
| FinishedCallback finishedCallback = FinishedCallback.obtain(finishedToken); |
| inputHandler.handleMotion(event, finishedCallback); |
| } |
| |
| /** |
| * A callback that must be invoked to when finished processing an event. |
| * @hide |
| */ |
| public static final class FinishedCallback { |
| private static final boolean DEBUG_RECYCLING = false; |
| |
| private static final int RECYCLE_MAX_COUNT = 4; |
| |
| private static FinishedCallback sRecycleHead; |
| private static int sRecycleCount; |
| |
| private FinishedCallback mRecycleNext; |
| private long mFinishedToken; |
| |
| private FinishedCallback() { |
| } |
| |
| public static FinishedCallback obtain(long finishedToken) { |
| synchronized (sLock) { |
| FinishedCallback callback = sRecycleHead; |
| if (callback != null) { |
| sRecycleHead = callback.mRecycleNext; |
| sRecycleCount -= 1; |
| callback.mRecycleNext = null; |
| } else { |
| callback = new FinishedCallback(); |
| } |
| callback.mFinishedToken = finishedToken; |
| return callback; |
| } |
| } |
| |
| public void finished(boolean handled) { |
| synchronized (sLock) { |
| if (mFinishedToken == -1) { |
| throw new IllegalStateException("Event finished callback already invoked."); |
| } |
| |
| nativeFinished(mFinishedToken, handled); |
| mFinishedToken = -1; |
| |
| if (sRecycleCount < RECYCLE_MAX_COUNT) { |
| mRecycleNext = sRecycleHead; |
| sRecycleHead = this; |
| sRecycleCount += 1; |
| |
| if (DEBUG_RECYCLING) { |
| Slog.d(TAG, "Recycled finished callbacks: " + sRecycleCount); |
| } |
| } |
| } |
| } |
| } |
| } |