1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.view;
18 
19 import dalvik.system.CloseGuard;
20 
21 import android.os.Looper;
22 import android.os.MessageQueue;
23 import android.util.Pools.Pool;
24 import android.util.Pools.SimplePool;
25 import android.util.LongSparseArray;
26 
27 import java.lang.ref.WeakReference;
28 
29 /**
30  * An input queue provides a mechanism for an application to receive incoming
31  * input events.  Currently only usable from native code.
32  */
33 public final class InputQueue {
34     private final LongSparseArray<ActiveInputEvent> mActiveEventArray =
35             new LongSparseArray<ActiveInputEvent>(20);
36     private final Pool<ActiveInputEvent> mActiveInputEventPool =
37             new SimplePool<ActiveInputEvent>(20);
38 
39     private final CloseGuard mCloseGuard = CloseGuard.get();
40 
41     private long mPtr;
42 
nativeInit(WeakReference<InputQueue> weakQueue, MessageQueue messageQueue)43     private static native long nativeInit(WeakReference<InputQueue> weakQueue,
44             MessageQueue messageQueue);
nativeSendKeyEvent(long ptr, KeyEvent e, boolean preDispatch)45     private static native long nativeSendKeyEvent(long ptr, KeyEvent e, boolean preDispatch);
nativeSendMotionEvent(long ptr, MotionEvent e)46     private static native long nativeSendMotionEvent(long ptr, MotionEvent e);
nativeDispose(long ptr)47     private static native void nativeDispose(long ptr);
48 
49     /** @hide */
InputQueue()50     public InputQueue() {
51         mPtr = nativeInit(new WeakReference<InputQueue>(this), Looper.myQueue());
52 
53         mCloseGuard.open("dispose");
54     }
55 
56     @Override
finalize()57     protected void finalize() throws Throwable {
58         try {
59             dispose(true);
60         } finally {
61             super.finalize();
62         }
63     }
64 
65     /** @hide */
dispose()66     public void dispose() {
67         dispose(false);
68     }
69 
70     /** @hide */
dispose(boolean finalized)71     public void dispose(boolean finalized) {
72         if (mCloseGuard != null) {
73             if (finalized) {
74                 mCloseGuard.warnIfOpen();
75             }
76             mCloseGuard.close();
77         }
78 
79         if (mPtr != 0) {
80             nativeDispose(mPtr);
81             mPtr = 0;
82         }
83     }
84 
85     /** @hide */
getNativePtr()86     public long getNativePtr() {
87         return mPtr;
88     }
89 
90     /** @hide */
sendInputEvent(InputEvent e, Object token, boolean predispatch, FinishedInputEventCallback callback)91     public void sendInputEvent(InputEvent e, Object token, boolean predispatch,
92             FinishedInputEventCallback callback) {
93         ActiveInputEvent event = obtainActiveInputEvent(token, callback);
94         long id;
95         if (e instanceof KeyEvent) {
96             id = nativeSendKeyEvent(mPtr, (KeyEvent) e, predispatch);
97         } else {
98             id = nativeSendMotionEvent(mPtr, (MotionEvent) e);
99         }
100         mActiveEventArray.put(id, event);
101     }
102 
finishInputEvent(long id, boolean handled)103     private void finishInputEvent(long id, boolean handled) {
104         int index = mActiveEventArray.indexOfKey(id);
105         if (index >= 0) {
106             ActiveInputEvent e = mActiveEventArray.valueAt(index);
107             mActiveEventArray.removeAt(index);
108             e.mCallback.onFinishedInputEvent(e.mToken, handled);
109             recycleActiveInputEvent(e);
110         }
111     }
112 
obtainActiveInputEvent(Object token, FinishedInputEventCallback callback)113     private ActiveInputEvent obtainActiveInputEvent(Object token,
114             FinishedInputEventCallback callback) {
115         ActiveInputEvent e = mActiveInputEventPool.acquire();
116         if (e == null) {
117             e = new ActiveInputEvent();
118         }
119         e.mToken = token;
120         e.mCallback = callback;
121         return e;
122     }
123 
recycleActiveInputEvent(ActiveInputEvent e)124     private void recycleActiveInputEvent(ActiveInputEvent e) {
125         e.recycle();
126         mActiveInputEventPool.release(e);
127     }
128 
129     private final class ActiveInputEvent {
130         public Object mToken;
131         public FinishedInputEventCallback mCallback;
132 
recycle()133         public void recycle() {
134             mToken = null;
135             mCallback = null;
136         }
137     }
138 
139     /**
140      * Interface to receive notification of when an InputQueue is associated
141      * and dissociated with a thread.
142      */
143     public static interface Callback {
144         /**
145          * Called when the given InputQueue is now associated with the
146          * thread making this call, so it can start receiving events from it.
147          */
onInputQueueCreated(InputQueue queue)148         void onInputQueueCreated(InputQueue queue);
149 
150         /**
151          * Called when the given InputQueue is no longer associated with
152          * the thread and thus not dispatching events.
153          */
onInputQueueDestroyed(InputQueue queue)154         void onInputQueueDestroyed(InputQueue queue);
155     }
156 
157     /** @hide */
158     public static interface FinishedInputEventCallback {
onFinishedInputEvent(Object token, boolean handled)159         void onFinishedInputEvent(Object token, boolean handled);
160     }
161 
162 }
163