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      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 #ifndef _UI_INPUT_MANAGER_H
     18 #define _UI_INPUT_MANAGER_H
     19 
     20 /**
     21  * Native input manager.
     22  */
     23 
     24 #include <ui/EventHub.h>
     25 #include <ui/Input.h>
     26 #include <utils/Errors.h>
     27 #include <utils/Vector.h>
     28 #include <utils/Timers.h>
     29 #include <utils/RefBase.h>
     30 #include <utils/String8.h>
     31 
     32 namespace android {
     33 
     34 class InputChannel;
     35 
     36 class InputReaderInterface;
     37 class InputReaderPolicyInterface;
     38 class InputReaderThread;
     39 
     40 class InputDispatcherInterface;
     41 class InputDispatcherPolicyInterface;
     42 class InputDispatcherThread;
     43 
     44 /*
     45  * The input manager is the core of the system event processing.
     46  *
     47  * The input manager uses two threads.
     48  *
     49  * 1. The InputReaderThread (called "InputReader") reads and preprocesses raw input events,
     50  *    applies policy, and posts messages to a queue managed by the DispatcherThread.
     51  * 2. The InputDispatcherThread (called "InputDispatcher") thread waits for new events on the
     52  *    queue and asynchronously dispatches them to applications.
     53  *
     54  * By design, the InputReaderThread class and InputDispatcherThread class do not share any
     55  * internal state.  Moreover, all communication is done one way from the InputReaderThread
     56  * into the InputDispatcherThread and never the reverse.  Both classes may interact with the
     57  * InputDispatchPolicy, however.
     58  *
     59  * The InputManager class never makes any calls into Java itself.  Instead, the
     60  * InputDispatchPolicy is responsible for performing all external interactions with the
     61  * system, including calling DVM services.
     62  */
     63 class InputManagerInterface : public virtual RefBase {
     64 protected:
     65     InputManagerInterface() { }
     66     virtual ~InputManagerInterface() { }
     67 
     68 public:
     69     /* Starts the input manager threads. */
     70     virtual status_t start() = 0;
     71 
     72     /* Stops the input manager threads and waits for them to exit. */
     73     virtual status_t stop() = 0;
     74 
     75     /* Gets the input reader. */
     76     virtual sp<InputReaderInterface> getReader() = 0;
     77 
     78     /* Gets the input dispatcher. */
     79     virtual sp<InputDispatcherInterface> getDispatcher() = 0;
     80 };
     81 
     82 class InputManager : public InputManagerInterface {
     83 protected:
     84     virtual ~InputManager();
     85 
     86 public:
     87     InputManager(
     88             const sp<EventHubInterface>& eventHub,
     89             const sp<InputReaderPolicyInterface>& readerPolicy,
     90             const sp<InputDispatcherPolicyInterface>& dispatcherPolicy);
     91 
     92     // (used for testing purposes)
     93     InputManager(
     94             const sp<InputReaderInterface>& reader,
     95             const sp<InputDispatcherInterface>& dispatcher);
     96 
     97     virtual status_t start();
     98     virtual status_t stop();
     99 
    100     virtual sp<InputReaderInterface> getReader();
    101     virtual sp<InputDispatcherInterface> getDispatcher();
    102 
    103 private:
    104     sp<InputReaderInterface> mReader;
    105     sp<InputReaderThread> mReaderThread;
    106 
    107     sp<InputDispatcherInterface> mDispatcher;
    108     sp<InputDispatcherThread> mDispatcherThread;
    109 
    110     void initialize();
    111 };
    112 
    113 } // namespace android
    114 
    115 #endif // _UI_INPUT_MANAGER_H
    116