android - torch 应用安卓

Question

你好，我想在 android 中实现 torch 应用程序，所以这是我的代码

    setContentView(R.layout.main);
    camera = Camera.open();
    if(camera == null)
        Toast.makeText(getBaseContext(),"CAMERA FAILED", Toast.LENGTH_LONG).show();
    else
        Toast.makeText(getBaseContext(),"camera opened",Toast.LENGTH_LONG).show();
}
public boolean dispatchKeyEvent(KeyEvent event) {
    int action = event.getAction();
    int keyCode = event.getKeyCode();
        switch (keyCode) {
        case KeyEvent.KEYCODE_VOLUME_UP:
            if (action == KeyEvent.ACTION_UP) {
                if(camera!=null)
                {
                     Toast.makeText(getBaseContext(),"came to volume up",Toast.LENGTH_LONG).show();
                     Parameters params = camera.getParameters();
                     params.setFlashMode( Parameters.FLASH_MODE_ON );
                     camera.setParameters(params);

                }
            }
            return true;
        case KeyEvent.KEYCODE_VOLUME_DOWN:
            if (action == KeyEvent.ACTION_UP) {
                Parameters params = camera.getParameters();
                params.setFlashMode( Parameters.FLASH_MODE_OFF );
                camera.setParameters(params);
                camera.release();
                camera = null;
                Toast.makeText(getBaseContext(),"came to volume down",Toast.LENGTH_LONG).show();
            }
            return true;
        default:
            return super.dispatchKeyEvent(event);
        }
    }

为什么这段代码不起作用？？？

Answer 1

杜尔迦，

我相信你想要FLASH_MODE_TORCH不是FLASH_MODE_ON当您按下音量增大键时。

可能需要以下权限:FLASHLIGHT和 CAMERA