我正在开发一个需要打开我的 Galaxy Nexus 设备的手电筒的应用程序。我在这里提到了帖子
Galaxy Nexus 上的 LED 手电筒可由什么 API 控制？
public class TestCamera extends Activity implements SurfaceHolder.Callback{
Camera mCamera;
public static SurfaceView preview;
public static SurfaceHolder mHolder;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
preview = (SurfaceView) findViewById(R.id.camSurface);
mHolder = preview.getHolder();
mCamera = Camera.open();
try {
mCamera.setPreviewDisplay(mHolder);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Button onLEDbtn = (Button) findViewById(R.id.onLED_btn);
onLEDbtn.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(), "test", Toast.LENGTH_SHORT).show();
Parameters params = mCamera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(params);
mCamera.startPreview();
}
});
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
}
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
mHolder = holder;
try {
mCamera.setPreviewDisplay(mHolder);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
mCamera.stopPreview();
mHolder = null;
}
}
显现：
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
但是，我仍然无法打开手电筒。谁能指出我的错误？谢谢