Android 按键 每次调节亮度时亮度框消失时间需要重新倒计时

Posted 2022-01-05 王睿丶

【思路】

• 1、每次点击亮度键时，我们需要发送一个广播给BrightnessDialog 进行后台计算
• 2、创建 num变量，表示 来回点击标志。
• 3、BrightnessDialog.java 的后台， 判断对话框是否需要自动关闭，每三秒请求一次，以num为状态标准
• 4、判断逻辑为：每次点击num+1，三秒后计时器请求判断对话框是否需要自动关闭，若num为0就会关闭，若num不为0，则继续显示且重新在后台计算。

frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java

public long interceptKeyBeforeDispatching(IBinder focusedToken, KeyEvent event,int policyFlags) 
        else if (keyCode == KeyEvent.KEYCODE_BRIGHTNESS_UP || keyCode == KeyEvent.KEYCODE_BRIGHTNESS_DOWN) 
            if (down) 
                //每次点击亮度按钮，都需要重新计算后台对话框自动消失的时间
                Intent intent = new Intent("xxx.brightness");
                mContext.sendBroadcast(intent);  
            
            return -1;
 

frameworks/base/packages/SystemUI/src/com/android/systemui/settings/BrightnessDialog.java

 		  //num表示 来回点击标志。
            private int num = 0;
            private TimerTask task;
            private Timer timer = new Timer();

			//只需单击亮度按钮即可标记 +1
            private final BroadcastReceiver myReceiver = new BroadcastReceiver() 
                @Override
                public void onReceive(Context context, Intent intent) 
                    num++;
                
            ;

			@Override
            protected void onStart() 
                super.onStart();
                //注册广播
                registerReceiver(myReceiver, new IntentFilter("xxx.brightness"));
                //判断对话框是否需要自动关闭，每三秒请求一次，以num为状态标准
                task = new TimerTask() 
                    @Override
                    public void run() 
                        if (num==0) finish();
                        num = 0;
                    
                ;
                timer.schedule(task,3000,3000);
            

			@Override
            protected void onStop() 
                super.onStop();
                MetricsLogger.hidden(this, MetricsEvent.BRIGHTNESS_DIALOG);
                mBrightnessController.unregisterCallbacks();
                //取消注册
                unregisterReceiver(myReceiver);
                //销毁计时器
                timer.cancel();
                task.cancel();
                timer = null;
                task = null;