| /* |
| * Copyright (C) 2011 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 dalvik.system.CloseGuard; |
| |
| import android.os.Looper; |
| import android.os.MessageQueue; |
| import android.util.Log; |
| |
| /** |
| * Provides a low-level mechanism for an application to receive display events |
| * such as vertical sync. |
| * |
| * The display event receive is NOT thread safe. Moreover, its methods must only |
| * be called on the Looper thread to which it is attached. |
| * |
| * @hide |
| */ |
| public abstract class DisplayEventReceiver { |
| private static final String TAG = "DisplayEventReceiver"; |
| |
| private final CloseGuard mCloseGuard = CloseGuard.get(); |
| |
| private long mReceiverPtr; |
| |
| // We keep a reference message queue object here so that it is not |
| // GC'd while the native peer of the receiver is using them. |
| private MessageQueue mMessageQueue; |
| |
| private static native long nativeInit(DisplayEventReceiver receiver, |
| MessageQueue messageQueue); |
| private static native void nativeDispose(long receiverPtr); |
| private static native void nativeScheduleVsync(long receiverPtr); |
| |
| /** |
| * Creates a display event receiver. |
| * |
| * @param looper The looper to use when invoking callbacks. |
| */ |
| public DisplayEventReceiver(Looper looper) { |
| if (looper == null) { |
| throw new IllegalArgumentException("looper must not be null"); |
| } |
| |
| mMessageQueue = looper.getQueue(); |
| mReceiverPtr = nativeInit(this, mMessageQueue); |
| |
| mCloseGuard.open("dispose"); |
| } |
| |
| @Override |
| protected void finalize() throws Throwable { |
| try { |
| dispose(true); |
| } finally { |
| super.finalize(); |
| } |
| } |
| |
| /** |
| * Disposes the receiver. |
| */ |
| public void dispose() { |
| dispose(false); |
| } |
| |
| private void dispose(boolean finalized) { |
| if (mCloseGuard != null) { |
| if (finalized) { |
| mCloseGuard.warnIfOpen(); |
| } |
| mCloseGuard.close(); |
| } |
| |
| if (mReceiverPtr != 0) { |
| nativeDispose(mReceiverPtr); |
| mReceiverPtr = 0; |
| } |
| mMessageQueue = null; |
| } |
| |
| /** |
| * Called when a vertical sync pulse is received. |
| * The recipient should render a frame and then call {@link #scheduleVsync} |
| * to schedule the next vertical sync pulse. |
| * |
| * @param timestampNanos The timestamp of the pulse, in the {@link System#nanoTime()} |
| * timebase. |
| * @param builtInDisplayId The surface flinger built-in display id such as |
| * {@link SurfaceControl#BUILT_IN_DISPLAY_ID_MAIN}. |
| * @param frame The frame number. Increases by one for each vertical sync interval. |
| */ |
| public void onVsync(long timestampNanos, int builtInDisplayId, int frame) { |
| } |
| |
| /** |
| * Called when a display hotplug event is received. |
| * |
| * @param timestampNanos The timestamp of the event, in the {@link System#nanoTime()} |
| * timebase. |
| * @param builtInDisplayId The surface flinger built-in display id such as |
| * {@link SurfaceControl#BUILT_IN_DISPLAY_ID_HDMI}. |
| * @param connected True if the display is connected, false if it disconnected. |
| */ |
| public void onHotplug(long timestampNanos, int builtInDisplayId, boolean connected) { |
| } |
| |
| /** |
| * Schedules a single vertical sync pulse to be delivered when the next |
| * display frame begins. |
| */ |
| public void scheduleVsync() { |
| if (mReceiverPtr == 0) { |
| Log.w(TAG, "Attempted to schedule a vertical sync pulse but the display event " |
| + "receiver has already been disposed."); |
| } else { |
| nativeScheduleVsync(mReceiverPtr); |
| } |
| } |
| |
| // Called from native code. |
| @SuppressWarnings("unused") |
| private void dispatchVsync(long timestampNanos, int builtInDisplayId, int frame) { |
| onVsync(timestampNanos, builtInDisplayId, frame); |
| } |
| |
| // Called from native code. |
| @SuppressWarnings("unused") |
| private void dispatchHotplug(long timestampNanos, int builtInDisplayId, boolean connected) { |
| onHotplug(timestampNanos, builtInDisplayId, connected); |
| } |
| } |