1 files changed, 199 insertions, 0 deletions
diff --git a/android/view/InputEventReceiver.java b/android/view/InputEventReceiver.java
new file mode 100644
index 00000000..c566a653
--- /dev/null
+++ b/android/view/InputEventReceiver.java
@@ -0,0 +1,199 @@
+/*
+ * 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 android.os.Looper;
+import android.os.MessageQueue;
+import android.util.Log;
+import android.util.SparseIntArray;
+
+import dalvik.system.CloseGuard;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Provides a low-level mechanism for an application to receive input events.
+ * @hide
+ */
+public abstract class InputEventReceiver {
+    private static final String TAG = "InputEventReceiver";
+
+    private final CloseGuard mCloseGuard = CloseGuard.get();
+
+    private long mReceiverPtr;
+
+    // We keep references to the input channel and message queue objects here so that
+    // they are not GC'd while the native peer of the receiver is using them.
+    private InputChannel mInputChannel;
+    private MessageQueue mMessageQueue;
+
+    // Map from InputEvent sequence numbers to dispatcher sequence numbers.
+    private final SparseIntArray mSeqMap = new SparseIntArray();
+
+    private static native long nativeInit(WeakReference<InputEventReceiver> receiver,
+            InputChannel inputChannel, MessageQueue messageQueue);
+    private static native void nativeDispose(long receiverPtr);
+    private static native void nativeFinishInputEvent(long receiverPtr, int seq, boolean handled);
+    private static native boolean nativeConsumeBatchedInputEvents(long receiverPtr,
+            long frameTimeNanos);
+
+    /**
+     * Creates an input event receiver bound to the specified input channel.
+     *
+     * @param inputChannel The input channel.
+     * @param looper The looper to use when invoking callbacks.
+     */
+    public InputEventReceiver(InputChannel inputChannel, Looper looper) {
+        if (inputChannel == null) {
+            throw new IllegalArgumentException("inputChannel must not be null");
+        }
+        if (looper == null) {
+            throw new IllegalArgumentException("looper must not be null");
+        }
+
+        mInputChannel = inputChannel;
+        mMessageQueue = looper.getQueue();
+        mReceiverPtr = nativeInit(new WeakReference<InputEventReceiver>(this),
+                inputChannel, 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;
+        }
+        mInputChannel = null;
+        mMessageQueue = null;
+    }
+
+    /**
+     * Called when an input event is received.
+     * The recipient should process the input event and then call {@link #finishInputEvent}
+     * to indicate whether the event was handled.  No new input events will be received
+     * until {@link #finishInputEvent} is called.
+     *
+     * @param displayId The display id on which input event triggered.
+     * @param event The input event that was received.
+     */
+    public void onInputEvent(InputEvent event, int displayId) {
+        finishInputEvent(event, false);
+    }
+
+    /**
+     * Called when a batched input event is pending.
+     *
+     * The batched input event will continue to accumulate additional movement
+     * samples until the recipient calls {@link #consumeBatchedInputEvents} or
+     * an event is received that ends the batch and causes it to be consumed
+     * immediately (such as a pointer up event).
+     */
+    public void onBatchedInputEventPending() {
+        consumeBatchedInputEvents(-1);
+    }
+
+    /**
+     * Finishes an input event and indicates whether it was handled.
+     * Must be called on the same Looper thread to which the receiver is attached.
+     *
+     * @param event The input event that was finished.
+     * @param handled True if the event was handled.
+     */
+    public final void finishInputEvent(InputEvent event, boolean handled) {
+        if (event == null) {
+            throw new IllegalArgumentException("event must not be null");
+        }
+        if (mReceiverPtr == 0) {
+            Log.w(TAG, "Attempted to finish an input event but the input event "
+                    + "receiver has already been disposed.");
+        } else {
+            int index = mSeqMap.indexOfKey(event.getSequenceNumber());
+            if (index < 0) {
+                Log.w(TAG, "Attempted to finish an input event that is not in progress.");
+            } else {
+                int seq = mSeqMap.valueAt(index);
+                mSeqMap.removeAt(index);
+                nativeFinishInputEvent(mReceiverPtr, seq, handled);
+            }
+        }
+        event.recycleIfNeededAfterDispatch();
+    }
+
+    /**
+     * Consumes all pending batched input events.
+     * Must be called on the same Looper thread to which the receiver is attached.
+     *
+     * This method forces all batched input events to be delivered immediately.
+     * Should be called just before animating or drawing a new frame in the UI.
+     *
+     * @param frameTimeNanos The time in the {@link System#nanoTime()} time base
+     * when the current display frame started rendering, or -1 if unknown.
+     *
+     * @return Whether a batch was consumed
+     */
+    public final boolean consumeBatchedInputEvents(long frameTimeNanos) {
+        if (mReceiverPtr == 0) {
+            Log.w(TAG, "Attempted to consume batched input events but the input event "
+                    + "receiver has already been disposed.");
+        } else {
+            return nativeConsumeBatchedInputEvents(mReceiverPtr, frameTimeNanos);
+        }
+        return false;
+    }
+
+    // Called from native code.
+    @SuppressWarnings("unused")
+    private void dispatchInputEvent(int seq, InputEvent event, int displayId) {
+        mSeqMap.put(event.getSequenceNumber(), seq);
+        onInputEvent(event, displayId);
+    }
+
+    // Called from native code.
+    @SuppressWarnings("unused")
+    private void dispatchBatchedInputEventPending() {
+        onBatchedInputEventPending();
+    }
+
+    public static interface Factory {
+        public InputEventReceiver createInputEventReceiver(
+                InputChannel inputChannel, Looper looper);
+    }
+}