Android中秒表的停止问题

Question

我在程序中创建了一个秒表 stopwatch，当然可以开始和停止。我用的以下的代码来实现这个功能。秒表可以开始，但是不能停止。

public class StopWatch2 extends Activity implements Runnable{

// text view influenced by the Thread
private TextView threadModifiedText;
int time=0;
Button b1,b2,b3;
/** Called when the activity is first created. */
Thread currentThread = new Thread(this);
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.stopwatch);

    b1=(Button)findViewById(R.id.button1);
    b2=(Button)findViewById(R.id.button2);
    b3=(Button)findViewById(R.id.button3);
    threadModifiedText = (TextView) findViewById(R.id.textView1);
    b1.setOnClickListener(new View.OnClickListener() 
    {
        public void onClick(View view) 
        {
            currentThread.start();
        }

    });     
    b2.setOnClickListener(new View.OnClickListener() 
    {
        public void onClick(View view) 
        {
            currentThread.stop();
        }

    });               
}

//Method you must override to control what the Thread is doing
@Override
public void run(){
    try {
        while(true){
            currentThread.sleep(1000, 0);
            threadHandler.sendEmptyMessage(0);
        }
        // signaling things to the outside world goes like this  

    } catch (InterruptedException e) {
    }   
} 
private Handler threadHandler = new Handler() {
    public void handleMessage(android.os.Message msg) {
        time++;
        threadModifiedText.setText(""+time);
    }
};
}

请求大家帮忙指出程序中的错误。谢谢！

Answer 1

你应该使用一个类变量boolean shouldRun = true ;在你的run（）方法中while应该这样

while(shouldRun)
{
 //implementation
}

在b2.onClickListener()改成shouldRun = false;