直播源码Android 屏幕常亮N秒后自动暗屏

// 最大的屏幕亮度   
private float maxLight;
// 当前的亮度  
private float currentLight;
// 用来控制屏幕亮度  
private Handler lightHandler;
// 60秒时间不点击屏幕，屏幕变暗 
private long delayTime = 60 * 1000L; 


protected void onCreate() {
	
	// 保持屏幕常亮
	getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
			WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
			
	// 屏幕亮度控制
	lightHandler = new Handler(Looper.getMainLooper());  
    maxLight = getLightness(); 
	
	
}

@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
	if (currentLight == 1) {
		startSleepTask();
		return false;
	}
   	startSleepTask();  
    return super.dispatchTouchEvent(ev);
}

/** 
 * 获取亮度 
 */  
private float getLightness() {
    WindowManager.LayoutParams localLayoutParams = this.getWindow().getAttributes();  
    return localLayoutParams.screenBrightness;  
}

/** 
 * 设置亮度  
 */  
private void setLightness(int light) {  
    currentLight = light;  
    WindowManager.LayoutParams localLayoutParams = this.getWindow().getAttributes();
    localLayoutParams.screenBrightness = (light / 255.0F);
    this.getWindow().setAttributes(localLayoutParams);
}

/** 
 * 开启休眠任务 
 */  
private void startSleepTask() {  
    setLightness((int) maxLight);  
    stopSleepTask();
    lightHandler.postDelayed(sleepWindowTask, delayTime);
}  

/** 
 * 结束休眠任务 
 */  
private void stopSleepTask() {  
	lightHandler.removeCallbacks(sleepWindowTask);  
}  

/** 
 * 休眠任务 
 */ 
Runnable sleepWindowTask = new Runnable() {  
    @Override  
    public void run() {
    	setLightness(1);  
    }  
};