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 android.compat.annotation.UnsupportedAppUsage;
20 import android.os.Looper;
21 import android.os.MessageQueue;
22 import android.util.LongSparseArray;
23 import android.util.Pools.Pool;
24 import android.util.Pools.SimplePool;
25 
26 import dalvik.system.CloseGuard;
27 
28 import java.lang.ref.WeakReference;
29 
30 /**
31  * An input queue provides a mechanism for an application to receive incoming
32  * input events.  Currently only usable from native code.
33  */
34 public final class InputQueue {
35     private final LongSparseArray<ActiveInputEvent> mActiveEventArray =
36             new LongSparseArray<ActiveInputEvent>(20);
37     private final Pool<ActiveInputEvent> mActiveInputEventPool =
38             new SimplePool<ActiveInputEvent>(20);
39 
40     private final CloseGuard mCloseGuard = CloseGuard.get();
41 
42     private long mPtr;
43 
nativeInit(WeakReference<InputQueue> weakQueue, MessageQueue messageQueue)44     private static native long nativeInit(WeakReference<InputQueue> weakQueue,
45             MessageQueue messageQueue);
nativeSendKeyEvent(long ptr, KeyEvent e, boolean preDispatch)46     private static native long nativeSendKeyEvent(long ptr, KeyEvent e, boolean preDispatch);
nativeSendMotionEvent(long ptr, MotionEvent e)47     private static native long nativeSendMotionEvent(long ptr, MotionEvent e);
nativeDispose(long ptr)48     private static native void nativeDispose(long ptr);
49 
50     /** @hide */
InputQueue()51     public InputQueue() {
52         mPtr = nativeInit(new WeakReference<InputQueue>(this), Looper.myQueue());
53 
54         mCloseGuard.open("dispose");
55     }
56 
57     @Override
finalize()58     protected void finalize() throws Throwable {
59         try {
60             dispose(true);
61         } finally {
62             super.finalize();
63         }
64     }
65 
66     /** @hide */
dispose()67     public void dispose() {
68         dispose(false);
69     }
70 
71     /** @hide */
dispose(boolean finalized)72     public void dispose(boolean finalized) {
73         if (mCloseGuard != null) {
74             if (finalized) {
75                 mCloseGuard.warnIfOpen();
76             }
77             mCloseGuard.close();
78         }
79 
80         if (mPtr != 0) {
81             nativeDispose(mPtr);
82             mPtr = 0;
83         }
84     }
85 
86     /** @hide */
getNativePtr()87     public long getNativePtr() {
88         return mPtr;
89     }
90 
91     /** @hide */
sendInputEvent(InputEvent e, Object token, boolean predispatch, FinishedInputEventCallback callback)92     public void sendInputEvent(InputEvent e, Object token, boolean predispatch,
93             FinishedInputEventCallback callback) {
94         ActiveInputEvent event = obtainActiveInputEvent(token, callback);
95         long id;
96         if (e instanceof KeyEvent) {
97             id = nativeSendKeyEvent(mPtr, (KeyEvent) e, predispatch);
98         } else {
99             id = nativeSendMotionEvent(mPtr, (MotionEvent) e);
100         }
101         mActiveEventArray.put(id, event);
102     }
103 
104     @UnsupportedAppUsage
finishInputEvent(long id, boolean handled)105     private void finishInputEvent(long id, boolean handled) {
106         int index = mActiveEventArray.indexOfKey(id);
107         if (index >= 0) {
108             ActiveInputEvent e = mActiveEventArray.valueAt(index);
109             mActiveEventArray.removeAt(index);
110             e.mCallback.onFinishedInputEvent(e.mToken, handled);
111             recycleActiveInputEvent(e);
112         }
113     }
114 
obtainActiveInputEvent(Object token, FinishedInputEventCallback callback)115     private ActiveInputEvent obtainActiveInputEvent(Object token,
116             FinishedInputEventCallback callback) {
117         ActiveInputEvent e = mActiveInputEventPool.acquire();
118         if (e == null) {
119             e = new ActiveInputEvent();
120         }
121         e.mToken = token;
122         e.mCallback = callback;
123         return e;
124     }
125 
recycleActiveInputEvent(ActiveInputEvent e)126     private void recycleActiveInputEvent(ActiveInputEvent e) {
127         e.recycle();
128         mActiveInputEventPool.release(e);
129     }
130 
131     private final class ActiveInputEvent {
132         public Object mToken;
133         public FinishedInputEventCallback mCallback;
134 
recycle()135         public void recycle() {
136             mToken = null;
137             mCallback = null;
138         }
139     }
140 
141     /**
142      * Interface to receive notification of when an InputQueue is associated
143      * and dissociated with a thread.
144      */
145     public static interface Callback {
146         /**
147          * Called when the given InputQueue is now associated with the
148          * thread making this call, so it can start receiving events from it.
149          */
onInputQueueCreated(InputQueue queue)150         void onInputQueueCreated(InputQueue queue);
151 
152         /**
153          * Called when the given InputQueue is no longer associated with
154          * the thread and thus not dispatching events.
155          */
onInputQueueDestroyed(InputQueue queue)156         void onInputQueueDestroyed(InputQueue queue);
157     }
158 
159     /** @hide */
160     public static interface FinishedInputEventCallback {
onFinishedInputEvent(Object token, boolean handled)161         void onFinishedInputEvent(Object token, boolean handled);
162     }
163 
164 }
165