1. 配置依赖项 在app的build.gradle文件中添加以下依赖项：

dependencies {
    implementation "androidx.camera:camera-camera2:1.1.0-alpha04"
    implementation 'com.google.android.material:material:1.2.0-alpha06'
}

2. 声明权限 在AndroidManifest.xml文件中添加以下权限：

3. 在布局文件中添加相机预览和ImageView 在布局文件中添加以下代码：

4. 初始化相机 在MainActivity onCreate()方法中添加以下代码：

private ListenableFuture cameraProviderFuture;
 
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
 
    cameraProviderFuture = ProcessCameraProvider.getInstance(this);
 
    cameraProviderFuture.addListener(() -> {
        try {
            // CameraProvider
            ProcessCameraProvider cameraProvider = cameraProviderFuture.get();
 
            // Preview
            Preview preview = new Preview.Builder().build();
            preview.setSurfaceProvider(previewView.createSurfaceProvider());
 
            // ImageCapture
            ImageCapture.Builder builder = new ImageCapture.Builder();
            ImageCapture imageCapture = builder.build();
 
            // ImageAnalysis
            ImageAnalysis.Builder builderImageAnalysis = new ImageAnalysis.Builder();
            ImageAnalysis imageAnalysis = builderImageAnalysis.build();
 
            // Select back camera
            CameraSelector cameraSelector = new CameraSelector.Builder()
                    .requireLensFacing(CameraSelector.LENS_FACING_BACK)
                    .build();
 
            // Attach use cases to the camera with the same lifecycle owner
            Camera camera = cameraProvider.bindToLifecycle((LifecycleOwner)this, cameraSelector, preview, imageCapture, imageAnalysis);
 
        } catch (Exception e) {
            Log.e(TAG, "Error occurred", e);
        }
    }, ContextCompat.getMainExecutor(this));
}

5. 拍照并显示在ImageView中 在MainActivity中添加以下代码：

private Executor executor = Executors.newSingleThreadExecutor();
private ImageCapture imageCapture = null;
 
public void takePicture(View view) {
    // 设置保存路径
    File file = new File