android多线程实例及总结

public class FirActivity extends Activity {
    static final int LOOPER_QUIT=-1;
    static final int LOOPER_BACK=1;
    public Handler handler_fat=new Handler()//主线程handler，用于接收子线程传来的消息，并且主线程默认有Looper；
        {
            public void handleMessage (Message msg)
            {
                if(msg.what==LOOPER_BACK)//接收子线程的消息
                {
                    Log.d("father","father->LOOPER_BACK");
                }
            }
        };
    public Handler handler_son;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button button=(Button)findViewById(R.id.button1);
        final Thread thread=new Thread(new Runnable() {
            public void run() {
                Looper.prepare();//子线程默认无looper，需开启looper；
                handler_son=new Handler()//子线程Handler，用于接收其他线程发送来的消息；
                {
                    public void handleMessage (Message msg)
                    {
                        if(msg.what==LOOPER_QUIT)
                        {
                            Log.d("thread", "prepare to go to death");
                            this.getLooper().quit();//结束Looper循环，子线程由于代码已执行完，准备死亡；
                        }
                        else if(msg.what==LOOPER_BACK)
                        {
                            Log.d("thread", "LOOPER_BACK");
                            handler_fat.sendEmptyMessage(LOOPER_BACK);//发送给主线程消息；
                        }
                        else
                        {
                            Log.d("thread", msg.what+"");
                        }
                          
                    }
                };
                Looper.loop();//Looper正式开始运行，代码执行到此开始循环，后面在结束之前不会执行；
                Log.d("thread", "going to death");
            }
        });
        thread.start();//线程开始启动
        button.setOnClickListener(new View.OnClickListener() {
              
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Log.d("main",thread.isAlive()+"");//换回thread是否存活，此处为true；
                handler_son.sendEmptyMessage(44);
                handler_son.sendEmptyMessage(LOOPER_BACK);
                handler_son.sendEmptyMessage(LOOPER_QUIT);
                Log.d("main",thread.isAlive()+"");//此处为false；
            }
        });
    }
}