Android HandlerThread的用法

HandlerThread 继承自Thread,内部封装了Looper。

首先Handler和HandlerThread的主要区别是:Handler与Activity在同一个线程中,HandlerThread与Activity不在同一个线程,而是别外新的线程中(Handler中不能做耗时的操作)。

用法:

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Handler.Callback;
import android.os.HandlerThread;
import android.os.Message; public class MainActivity extends Activity {
HandlerThread handlerThread = new HandlerThread("test");
Handler handler; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
System.out.println("cur_id="+Thread.currentThread().getId()); handlerThread.start();
System.out.println("handlerThread.id=" + handlerThread.getId());
//post(runnable),只是直接运行了run(),run()内ThreadId与UIThread是一样的
// handler = new Handler();
//post(runnable),将runnable运行在handlerThread中,这是非UIThread的
handler = new Handler(handlerThread.getLooper(), new Callback() { @Override
public boolean handleMessage(Message msg) {
System.out.println("receive message.whatA=" + msg.what);
if (msg.what == ) {
return true;//不再向外层传递
} else {
return false; //外层的handleMessage() 继续执行
} }
}) {
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
super.handleMessage(msg);
System.out.println("receive message.whatB=" + msg.what);
}
};
handler.post(new Runnable() { @Override
public void run() {
System.out.println("handler_post_cur_id="+Thread.currentThread().getId());
handler.sendEmptyMessage();
handler.sendEmptyMessage();
}
}); } }

运行结果:

- ::31.590: I/System.out(): cur_id=
- ::31.590: I/System.out(): handlerThread.id=
- ::31.590: I/System.out(): handler_post_cur_id=
- ::31.600: I/System.out(): receive message.whatA=
- ::31.600: I/System.out(): receive message.whatA=
- ::31.600: I/System.out(): receive message.whatB=
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