要在Android上使用相机捕捉整个图像，可以使用Camera API或Camera2 API。

下面是一个使用Camera API的示例代码：

import android.app.Activity;
import android.content.Context;
import android.content.pm.PackageManager;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity implements SurfaceHolder.Callback {

    private Camera camera;
    private SurfaceView surfaceView;
    private SurfaceHolder surfaceHolder;
    private boolean previewing = false;

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

        surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);

        Button captureButton = (Button) findViewById(R.id.captureButton);
        captureButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (camera != null) {
                    camera.takePicture(null, null, pictureCallback);
                }
            }
        });
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        if (!checkCameraHardware(this)) {
            return;
        }

        camera = Camera.open();
        camera.setDisplayOrientation(90);

        try {
            camera.setPreviewDisplay(holder);
            camera.startPreview();
            previewing = true;
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        if (previewing) {
            camera.stopPreview();
            previewing = false;
        }

        try {
            camera.setPreviewDisplay(holder);
            camera.startPreview();
            previewing = true;
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        if (camera != null) {
            camera.stopPreview();
            camera.release();
            camera = null;
            previewing = false;
        }
    }

    private Camera.PictureCallback pictureCallback = new Camera.PictureCallback() {
        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            // 处理捕捉到的图像数据
        }
    };

    private boolean checkCameraHardware(Context context) {
        if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
            return true;
        } else {
            return false;
        }
    }
}

上面的代码使用了SurfaceView来预览相机捕捉的图像，并通过Camera.PictureCallback来获取捕捉到的图像数据。当点击按钮时，调用camera.takePicture()方法进行拍照。

请注意，这是使用Camera API的旧方法，如果您的应用程序目标为Android 5.0（API级别21）或更高版本，建议使用Camera2 API进行相机操作。

如果您要使用Camera2 API，请参考以下示例代码：

import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.pm.PackageManager;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.TotalCaptureResult;
import android.os.Bundle;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.util.Size;
import android.util.SparseIntArray;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;

import java.util.Arrays;

public class MainActivity extends Activity {

    private static final int REQUEST_CAMERA_PERMISSION = 200;
    private SurfaceView surfaceView;
    private Button captureButton;
    private CameraDevice cameraDevice;
    private CaptureRequest.Builder captureRequestBuilder;
    private CameraCaptureSession cameraCaptureSession;
    private Size imageDimension;
    private Handler backgroundHandler;
    private SurfaceHolder surfaceHolder;

    private final CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {

        @Override
        public void onOpened(@NonNull CameraDevice camera) {
            cameraDevice = camera;
            createCameraPreview();
        }

        @Override
        public void onDisconnected(@NonNull CameraDevice camera) {
            cameraDevice.close();
        }

        @Override
        public void onError(@NonNull CameraDevice camera, int error) {
            cameraDevice.close();
            cameraDevice