Android中的时间延时问题

Question

我想在应用程序中创建一个闪光点效果。为此我需要一个时间延迟,一个是100 ms，其它是20ms。这是我使用的代码：

Thread timer = new Thread();
    long longTime = 100;
    long shortTime = 20;
    for (int x = 0; x < 2000000; x++)
    {
        layout.setBackgroundColor(background);
        try {
            timer.sleep(longTime);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        layout.setBackgroundColor(backgroundBlack);
        try {
            timer.sleep(shortTime);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

问题是,当我单击按钮来调用该代码,没有出现所要的效果。所以我做了一点调试且确信它是定时调用。但是我不确定如何调用一个休眠线程。

Answer 1

你应该使用Handler来实现

public class Strobe extends Activity {

    private LinearLayout mLinearLayout;

    private Handler mHander = new Handler();

    private boolean mActive = false;
    private boolean mSwap = true;   

    private final Runnable mRunnable = new Runnable() {

        public void run() {         
            if (mActive) {
                if (mSwap) {                    
                    mLinearLayout.setBackgroundColor(Color.WHITE);
                    mSwap = false;
                    mHander.postDelayed(mRunnable, 20);
                } else {
                    mLinearLayout.setBackgroundColor(Color.BLACK);
                    mSwap = true;
                    mHander.postDelayed(mRunnable, 100);
                }
            }           
        }
    };

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mLinearLayout = (LinearLayout) findViewById(R.id.strobe);
        startStrobe();
    }

    private void startStrobe() {        
        mActive = true;
        mHander.post(mRunnable);
    }
}

给活动设置一个主题，让它全屏显示。

android:theme="@android:style/Theme.NoTitleBar.Fullscreen"