java - 在应用程序关闭时使手电筒应用程序工作

Question

我有这段代码，可以让我按下按钮打开手机手电筒。在应用程序关闭时保持灯亮的最佳方法是什么？我听说 asynctask 很好，但我读到它是用于将与 UI 通信的后台任务。这种“应用”应该用什么样的“线程”。

我的 onClickListener 代码:

button.setOnClickListener(new OnClickListener() {
            public void onClick(View arg0) {
        //If Flag is set to true
        if (isFlashOn) {
        Log.i("info", "torch is turned off!");
        //Set the flashmode to off                    
        p.setFlashMode(Parameters.FLASH_MODE_OFF);
        //Pass the parameter ti camera object
        camera.setParameters(p);    
        //Set flag to false                
        isFlashOn = false;
        //Set the button text to Torcn-ON
        button.setText("Torch-ON");
        } 
        //If Flag is set to false
        else {
        Log.i("info", "torch is turned on!");
        //Set the flashmode to on
        p.setFlashMode(Parameters.FLASH_MODE_TORCH);
        //Pass the parameter ti camera object
        camera.setParameters(p);
        //Set flag to true
        isFlashOn = true;
        //Set the button text to Torcn-OFF
        button.setText("Torch-OFF");
        }
            }});


    }

Answer 1

听起来您需要 service

A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use