android的定时及消息队列处理

  最近在做项目的时候，发觉有很多需要工作线程及消息处理的地方，而android自身提供了很好的包装类，这里对自己使用的一些梳理，权作自己的笔记。

主要有几种实现方式：

1.使用Handler.postAtTime定时将Runnable作为工作线程，处理耗时工作；

2.通过使用HandlerThread；

3.自定义Thread，并实现消息循环。

代码1：Runnable片段

private Handler mTickerHandler = new Handler();private Runnable mTicker = new Runnable() {public void run() {if (mTickerStop) {return;}if (!mTickerSkip) {// TODO 执行实际的工作}long time = SystemClock.uptimeMillis();long step = time - time % 1000L + 1000L * STEP;// time - time % 1000L此处的减去求余操作，是为了将定时设置在整数秒上mTickerHandler.postAtTime(MainActivity.this.mTicker, step);}};

代码2：HandlerThread

private final class ServiceHandler extends Handler {public ServiceHandler(Looper looper) {super(looper);}@Overridepublic void handleMessage(Message msg) {int what = msg.what;trace("Thread:" + Thread.currentThread() + ", msg:" + msg);// 执行任务操作}}@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);// 此处定义了两个工作线程，并将工作线程并设置响应的消息处理的handlerHandlerThread senderThread = new HandlerThread("[sender_service]");senderThread.start();mSenderServiceLooper = senderThread.getLooper();mSenderServiceHandler = new ServiceHandler(mSenderServiceLooper);HandlerThread receiverThread = new HandlerThread("[receiver_service]");receiverThread.start();mReceiverServiceLooper = receiverThread.getLooper();mReceiverServiceHandler = new ServiceHandler(mReceiverServiceLooper);// 开启定时处理startTicker();}@Overrideprotected void onDestroy() {super.onDestroy();stopTicker(false);// 销毁时要调用quit方法，将工作线程的消息循环停止mSenderServiceLooper.quit();mReceiverServiceLooper.quit();}

代码3：Thread进行消息处理

public Handler mExportHandler;private static final int _QUIT = -1;private static final int _STEP = 0;private static final int _START = 1;private static final int _END = 2;private static final int _FAIL = 3;

new Thread() {private int preNext = 0;public void run() {Looper.prepare();mExportHandler = new Handler() {public void handleMessage(Message msg) {System.out.println("msg=" + msg);switch (msg.what) {case _QUIT:Looper.myLooper().quit();break;case _STEP:int next = exports(isSender, msg.arg1);if (next > 15) {mExportHandler.sendEmptyMessage(_QUIT);return;}if (preNext == next) {mExportHandler.sendMessageDelayed(mExportHandler.obtainMessage(_STEP,next, 0), 5000L);} else {preNext = next;mExportHandler.sendMessage(mExportHandler.obtainMessage(_STEP, next, 0));}break;case _START:break;case _END:case _FAIL:mReporter.report(ProcessReport.STATE_BACKUP_CONTACTS,msg.arg1, msg.arg2, msg.obj);break;}}};mExportHandler.sendMessage(mExportHandler.obtainMessage(_STEP,0, 0));Looper.loop();}}.start();

注意退出时发送mExportHandler.sendEmptyMessage(_QUIT);

因为项目中需要分步骤进行处理，在一个步骤上失败后需要进行间隔尝试

next > 15时作退出处理，15只是一个步骤定义，可以指定更多或更少。

private int exports(boolean isSender, int step) {int next = step;try {if (next == 0) {// 步骤一if (!excutore(...)) {// 失败时next保持不变，直接放回，定时间隔后再次执行return next;}// 执行成功后，进行下一步操作next++;}if (next == 1) {// 步骤二if (!excutore(...)) {// 失败时next保持不变，直接放回，定时间隔后再次执行return next;}}// 其他步骤依此...// > 15则退出循环next = 16;} catch (Exception e) {AdbDebug.LogException(e);}return next;}

代码1、2的完整代码

import android.app.Activity;import android.os.Bundle;import android.os.Handler;import android.os.HandlerThread;import android.os.Looper;import android.os.Message;import android.os.SystemClock;public class MainActivity extends Activity {private static final boolean DEBUG = false;private static final long STEP = 15L;private boolean mTickerStop = true;private boolean mTickerSkip;private volatile Looper mSenderServiceLooper;private volatile Looper mReceiverServiceLooper;private volatile ServiceHandler mSenderServiceHandler;private volatile ServiceHandler mReceiverServiceHandler;private Handler mTickerHandler = new Handler();private Runnable mTicker = new Runnable() {public void run() {if (mTickerStop) {return;}if (!mTickerSkip) {// TODO 执行实际的工作}long time = SystemClock.uptimeMillis();long step = time - time % 1000L + 1000L * STEP;// time - time % 1000L此处的减去求余操作，是为了将定时设置在整数秒上mTickerHandler.postAtTime(MainActivity.this.mTicker, step);}};private final class ServiceHandler extends Handler {public ServiceHandler(Looper looper) {super(looper);}@Overridepublic void handleMessage(Message msg) {int what = msg.what;trace("Thread:" + Thread.currentThread() + ", msg:" + msg);// 执行任务操作}}@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);// 此处定义了两个工作线程，并将工作线程并设置响应的消息处理的handlerHandlerThread senderThread = new HandlerThread("[sender_service]");senderThread.start();mSenderServiceLooper = senderThread.getLooper();mSenderServiceHandler = new ServiceHandler(mSenderServiceLooper);HandlerThread receiverThread = new HandlerThread("[receiver_service]");receiverThread.start();mReceiverServiceLooper = receiverThread.getLooper();mReceiverServiceHandler = new ServiceHandler(mReceiverServiceLooper);// 开启定时处理startTicker();}@Overrideprotected void onDestroy() {super.onDestroy();stopTicker(false);// 销毁时要调用quit方法，将工作线程的消息循环停止mSenderServiceLooper.quit();mReceiverServiceLooper.quit();}private void startTicker() {mTickerSkip = false;if (mTickerStop) {mTickerStop = false;mTicker.run();}}private void stopTicker(boolean isStop) {if (isStop && !mTickerStop) {// 当前没有停止时，则移除消息队列中的消息，并将mTickerStop赋值truemTickerHandler.removeCallbacks(mTicker);mTickerStop = true;}mTickerSkip = true;}}