可以写出相关代码不

当然可以，以下是 Camera 拍照应用的相关代码实现。

1. 在 AndroidManifest.xml 文件中添加相应的权限：

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

2. 创建 MainActivity 和 CameraActivity 两个 Activity，并在 MainActivity 中添加一个按钮，用于触发跳转到 CameraActivity 的操作。

MainActivity.java

public class MainActivity extends AppCompatActivity {

    private static final int REQUEST_CODE_CAMERA = 1;

    private RecyclerView mRecyclerView;
    private PhotoListAdapter mAdapter;
    private List<PhotoItem> mPhotoList;

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

        mRecyclerView = findViewById(R.id.recycler_view);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
        mPhotoList = new ArrayList<>();
        mAdapter = new PhotoListAdapter(this, mPhotoList);
        mRecyclerView.setAdapter(mAdapter);

        Button btnCamera = findViewById(R.id.btn_camera);
        btnCamera.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, CameraActivity.class);
                startActivityForResult(intent, REQUEST_CODE_CAMERA);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_CODE_CAMERA && resultCode == RESULT_OK) {
            String filePath = data.getStringExtra(CameraActivity.EXTRA_FILE_PATH);
            long timeTaken = data.getLongExtra(CameraActivity.EXTRA_TIME_TAKEN, 0);
            mPhotoList.add(new PhotoItem(filePath, timeTaken));
            mAdapter.notifyDataSetChanged();
        }
    }
}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/btn_camera"
        android:text="拍照"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>

3. 在 CameraActivity 中添加 SurfaceView 和按钮，并实现相应的 Camera 操作。

CameraActivity.java

public class CameraActivity extends AppCompatActivity implements SurfaceHolder.Callback, Camera.PictureCallback {

    public static final String EXTRA_FILE_PATH = "file_path";
    public static final String EXTRA_TIME_TAKEN = "time_taken";

    private SurfaceView mSurfaceView;
    private Camera mCamera;
    private File mFile;

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

        mSurfaceView = findViewById(R.id.surface_view);
        mSurfaceView.getHolder().addCallback(this);

        Button btnTakePicture = findViewById(R.id.btn_take_picture);
        btnTakePicture.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mCamera.takePicture(null, null, CameraActivity.this);
            }
        });

        Button btnCancel = findViewById(R.id.btn_cancel);
        btnCancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
            }
        });
    }

    @Override
    public void surfaceCreated(SurfaceHolder surfaceHolder) {
        try {
            mCamera = Camera.open();
            mCamera.setPreviewDisplay(surfaceHolder);
            mCamera.startPreview();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder surfaceHolder, int i, int i1, int i2) {
        if (mCamera != null) {
            mCamera.stopPreview();
            try {
                mCamera.setPreviewDisplay(surfaceHolder);
                mCamera.startPreview();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
        if (mCamera != null) {
            mCamera.stopPreview();
            mCamera.release();
            mCamera = null;
        }
    }

    @Override
    public void onPictureTaken(byte[] bytes, Camera camera) {
        mFile = getOutputMediaFile();
        if (mFile == null) {
            Toast.makeText(this, "Failed to create file.", Toast.LENGTH_SHORT).show();
            return;
        }

        try {
            FileOutputStream fos = new FileOutputStream(mFile);
            fos.write(bytes);
            fos.close();

            Intent intent = new Intent();
            intent.putExtra(EXTRA_FILE_PATH, mFile.getAbsolutePath());
            intent.putExtra(EXTRA_TIME_TAKEN, System.currentTimeMillis());
            setResult(RESULT_OK, intent);

            mSurfaceView.setVisibility(View.GONE);
            findViewById(R.id.btn_take_picture).setVisibility(View.GONE);
            findViewById(R.id.btn_cancel).setVisibility(View.GONE);
            findViewById(R.id.iv_photo).setVisibility(View.VISIBLE);
            ((ImageView) findViewById(R.id.iv_photo)).setImageBitmap(BitmapFactory.decodeFile(mFile.getAbsolutePath()));

            new Handler().postDelayed(new Runnable() {
                @Override
                public void run() {
                    finish();
                }
            }, 3000);

        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private File getOutputMediaFile() {
        File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES), "MyCameraApp");
        if (!mediaStorageDir.exists()) {
            if (!mediaStorageDir.mkdirs()) {
                return null;
            }
        }
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        return new File(mediaStorageDir.getPath() + File.separator + "IMG_" + timeStamp + ".jpg");
    }
}

activity_camera.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <SurfaceView
        android:id="@+id/surface_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <RelativeLayout
        android:id="@+id/layout_buttons"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:orientation="horizontal">

        <Button
            android:id="@+id/btn_take_picture"
            android:text="拍照"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1" />

        <Button
            android:id="@+id/btn_cancel"
            android:text="取消"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1" />

    </RelativeLayout>

    <ImageView
        android:id="@+id/iv_photo"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:visibility="gone" />

</RelativeLayout>

4. 创建 PhotoListAdapter 和 PhotoItem 两个类，用于显示图片列表。

PhotoListAdapter.java

public class PhotoListAdapter extends RecyclerView.Adapter<PhotoListAdapter.ViewHolder> {

    private Context mContext;
    private List<PhotoItem> mPhotoList;

    public PhotoListAdapter(Context context, List<PhotoItem> photoList) {
        mContext = context;
        mPhotoList = photoList;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(mContext).inflate(R.layout.item_photo, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        PhotoItem item = mPhotoList.get(position);
        holder.ivPhoto.setImageBitmap(BitmapFactory.decodeFile(item.getFilePath()));
        holder.tvTime.setText(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date(item.getTimeTaken())));
    }

    @Override
    public int getItemCount() {
        return mPhotoList.size();
    }

    static class ViewHolder extends RecyclerView.ViewHolder {

        ImageView ivPhoto;
        TextView tvTime;

        ViewHolder(View itemView) {
            super(itemView);
            ivPhoto = itemView.findViewById(R.id.iv_photo);
            tvTime = itemView.findViewById(R.id.tv_time);
        }
    }
}

item_photo.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="80dp">

    <ImageView
        android:id="@+id/iv_photo"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:layout_margin="10dp" />

    <TextView
        android:id="@+id/tv_time"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@id/iv_photo"
        android:layout_alignParentRight="true"
        android:text="2022-01-01 12:00:00"
        android:textSize="12sp" />

</RelativeLayout>

PhotoItem.java

public class PhotoItem {

    private String mFilePath;
    private long mTimeTaken;

    public PhotoItem(String filePath, long timeTaken) {
        mFilePath = filePath;
        mTimeTaken = timeTaken;
    }

    public String getFilePath() {
        return mFilePath;
    }

    public long getTimeTaken() {
        return mTimeTaken;
    }
}

以上就是一个简单的 Camera 拍照应用的代码实现。需要注意的是，该应用使用了 Camera API，而 Camera API 在 Android 5.0 之后被废弃，建议使用 Camera2 API 替代。同时，还需要注意内存泄漏、适配不同分辨率设备等问题。