android - 如何在按钮上设置倒计时？

Question

我有一个 Button，按下后应该开始倒计时并在按钮上显示倒计时。

我该如何继续？

Answer 1

试试这个

public class CountDown extends Activity implements OnClickListener {

    Button btn;
    int i=0, second = 3;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        btn = (Button)findViewById(R.id.btn);
        btn.setOnClickListener( this );
    }

    @Override
    public void onClick(View v) {
        new Thread( new Runnable() {
                public void run() {
                    while( i != second ) {
                        try {
                            handle.sendMessage( handle.obtainMessage());
                            Thread.sleep(1000);
                        } catch( Throwable t) {

                        }   
                    }
                }  

                Handler handle = new Handler() {
                    public void handleMessage( Message msg) {
                        btn.setText( ""+ second );
                        second--;
                    }           
                };
        }).start();   

    }
}