1.使用carmear简单实现手电筒功能

初始值设置：

private Camera camera = null;private boolean isOpen = false;

 onCreate中添加代码：

if (camera == null) {    camera = Camera.open();}

onDer中添加：

@Overrideprotected void onDestroy() {	camera.release();	camera = null;	super.onDestroy();}

 主要方法：

private void openFlashLight() {	Camera.Parameters param = camera.getParameters();	if (!isOpen) {//            getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);		param.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);	} else {		param.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);	}	camera.setParameters(param);	isOpen = !isOpen;}