打开Camera的手电筒

private Camera camera;
private Boolean flashlight_is_open = false;



flash_light.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Camera.Parameters parameters = camera.getParameters();
                if (flashlight_is_open==false){
                    flash_light.setImageDrawable(getResources().getDrawable(R.drawable.flashlight_open));
                    flashlight_is_open = true;
                    parameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
                    camera.setParameters(parameters);
                }else {
                    flash_light.setImageDrawable(getResources().getDrawable(R.drawable.flashlight));
                    flashlight_is_open = false;
                    parameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
                    camera.setParameters(parameters);
                }
            }
        });

最后，别忘了权限：

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
<uses-permission android:name="android.permission.FLASHLIGHT" />