讓Android組件懸浮所有頁面之上

import android.app.Activity;  
import android.graphics.Color;  
import android.os.Bundle;  
import android.view.WindowManager;  
import android.view.WindowManager.LayoutParams;  
import android.widget.TextView;  

public class MainActivity extends Activity {  

    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        WindowManager wm = (WindowManager) getApplicationContext()  
                .getSystemService(WINDOW_SERVICE);  
        WindowManager.LayoutParams lp = new WindowManager.LayoutParams();  
        // 懸浮所有頁面之上  
        lp.type = WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY;  
        lp.width = WindowManager.LayoutParams.WRAP_CONTENT;  
        lp.height = WindowManager.LayoutParams.WRAP_CONTENT;  
        // 失去焦點  
        lp.flags = LayoutParams.FLAG_NOT_TOUCH_MODAL  
                | LayoutParams.FLAG_NOT_FOCUSABLE;  
        TextView tv = new TextView(this);  
        tv.setText("我是不是你最疼愛的人，你為什么不說話，握住是你冰冷的手動也不動讓我好難過");  
        tv.setBackgroundColor(Color.WHITE);  
        wm.addView(tv, lp);  
    }  

}