如何在屏幕上方实现JavaCameraView

// 导入相应的库和依赖
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.core.Mat;

// 在布局文件中添加JavaCameraView
<org.opencv.android.JavaCameraView
    android:id="@+id/java_camera_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_alignParentTop="true" />

// 在Java代码中实现相机预览
public class MainActivity extends AppCompatActivity implements CameraBridgeViewBase.CvCameraViewListener2 {
    private JavaCameraView javaCameraView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // 初始化JavaCameraView
        javaCameraView = (JavaCameraView) findViewById(R.id.java_camera_view);
        javaCameraView.setVisibility(SurfaceView.VISIBLE);
        javaCameraView.setCvCameraViewListener(this);
    }

    @Override
    public void onResume() {
        super.onResume();
        javaCameraView.enableView();
    }

    @Override
    public void onPause() {
        super.onPause();
        if (javaCameraView != null)
            javaCameraView.disableView();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (javaCameraView != null)
            javaCameraView.disableView();
    }

    @Override
    public void onCameraViewStarted(int width, int height) {
    }

    @Override
    public void onCameraViewStopped() {
    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
        // 处理相机帧数据
        Mat frame = inputFrame.rgba();
        // 在这里可以对帧数据进行处理或分析
        return frame;
    }
}