怎么将相机拍出的照片传送到编辑页面，编辑页面照片和文本框，点击save按钮后保存到Room数据库，点击cancel按钮，返回相机拍照界面，并且删除该照片，完整示例

首先，我们需要在相机拍照界面上添加一个按钮，用于跳转到编辑页面，并将拍摄的照片传递到编辑页面。可以使用以下代码：

<Button
    android:id="@+id/edit_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Edit"
    android:onClick="editPhoto" />

在 `MainActivity` 中，编写 `editPhoto` 方法，用于跳转到编辑页面并传递照片路径：

public void editPhoto(View view) {
    Intent intent = new Intent(this, EditActivity.class);
    intent.putExtra("photoPath", currentPhotoPath);
    startActivityForResult(intent, EDIT_REQUEST_CODE);
}

这里使用 `startActivityForResult` 方法来启动编辑页面，并在返回时获取编辑结果。需要在 `onActivityResult` 方法中处理编辑结果：

@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == EDIT_REQUEST_CODE && resultCode == RESULT_OK) {
        // 获取编辑后的结果
        String text = data.getStringExtra("text");
        String photoPath = data.getStringExtra("photoPath");
        // 保存到数据库
        saveToDatabase(text, photoPath);
        // 删除照片
        File file = new File(photoPath);
        file.delete();
        // 返回相机拍照界面
        dispatchTakePictureIntent();
    }
}

在编辑页面中，我们需要显示照片和文本框，并在点击保存按钮时将编辑结果返回到 `MainActivity`。可以使用以下代码：

<ImageView
    android:id="@+id/photo_image_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true"
    android:src="@drawable/placeholder" />

<EditText
    android:id="@+id/text_edit_text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="Enter your text here" />

<Button
    android:id="@+id/save_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Save"
    android:onClick="savePhoto" />

<Button
    android:id="@+id/cancel_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Cancel"
    android:onClick="cancelPhoto" />

在 `EditActivity` 中，编写 `savePhoto` 方法，用于返回编辑结果。需要使用 `setResult` 方法设置返回结果，并在点击保存按钮时关闭当前页面：

public void savePhoto(View view) {
    String text = editText.getText().toString();
    Intent intent = new Intent();
    intent.putExtra("text", text);
    intent.putExtra("photoPath", photoPath);
    setResult(RESULT_OK, intent);
    finish();
}

在 `EditActivity` 中，编写 `cancelPhoto` 方法，用于返回相机拍照界面并删除照片。需要使用 `setResult` 方法设置返回结果，并在点击取消按钮时关闭当前页面：

public void cancelPhoto(View view) {
    File file = new File(photoPath);
    file.delete();
    setResult(RESULT_CANCELED);
    finish();
}

最后，在 `MainActivity` 中，编写 `saveToDatabase` 方法，用于将照片和文本保存到 Room 数据库：

private void saveToDatabase(String text, String photoPath) {
    PhotoDao photoDao = AppDatabase.getInstance(this).photoDao();
    Photo photo = new Photo(text, photoPath);
    photoDao.insert(photo);
}

完整代码示例：

`MainActivity.java`

public class MainActivity extends AppCompatActivity {

    static final int REQUEST_IMAGE_CAPTURE = 1;
    static final int EDIT_REQUEST_CODE = 2;
    String currentPhotoPath;

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

    public void dispatchTakePictureIntent() {
        Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
            File photoFile = null;
            try {
                photoFile = createImageFile();
            } catch (IOException ex) {
                // Error occurred while creating the File
                ex.printStackTrace();
            }
            if (photoFile != null) {
                Uri photoURI = FileProvider.getUriForFile(this,
                        "com.example.android.fileprovider",
                        photoFile);
                takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
                startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
            }
        }
    }

    private File createImageFile() throws IOException {
        // Create an image file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String imageFileName = "JPEG_" + timeStamp + "_";
        File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
        File image = File.createTempFile(
                imageFileName,  /* prefix */
                ".jpg",         /* suffix */
                storageDir      /* directory */
        );

        // Save a file: path for use with ACTION_VIEW intents
        currentPhotoPath = image.getAbsolutePath();
        return image;
    }

    public void editPhoto(View view) {
        Intent intent = new Intent(this, EditActivity.class);
        intent.putExtra("photoPath", currentPhotoPath);
        startActivityForResult(intent, EDIT_REQUEST_CODE);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
            // Show the thumbnail on ImageView
            ImageView imageView = findViewById(R.id.photo_image_view);
            Bitmap bitmap = BitmapFactory.decodeFile(currentPhotoPath);
            imageView.setImageBitmap(bitmap);
        } else if (requestCode == EDIT_REQUEST_CODE && resultCode == RESULT_OK) {
            // Get the edited text and photo path
            String text = data.getStringExtra("text");
            String photoPath = data.getStringExtra("photoPath");
            // Save to database
            saveToDatabase(text, photoPath);
            // Delete the photo
            File file = new File(photoPath);
            file.delete();
            // Return to camera view
            dispatchTakePictureIntent();
        }
    }

    private void saveToDatabase(String text, String photoPath) {
        PhotoDao photoDao = AppDatabase.getInstance(this).photoDao();
        Photo photo = new Photo(text, photoPath);
        photoDao.insert(photo);
    }
}

`EditActivity.java`

public class EditActivity extends AppCompatActivity {

    EditText editText;
    String photoPath;

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

        editText = findViewById(R.id.text_edit_text);

        Intent intent = getIntent();
        photoPath = intent.getStringExtra("photoPath");

        ImageView imageView = findViewById(R.id.photo_image_view);
        Bitmap bitmap = BitmapFactory.decodeFile(photoPath);
        imageView.setImageBitmap(bitmap);
    }

    public void savePhoto(View view) {
        String text = editText.getText().toString();
        Intent intent = new Intent();
        intent.putExtra("text", text);
        intent.putExtra("photoPath", photoPath);
        setResult(RESULT_OK, intent);
        finish();
    }

    public void cancelPhoto(View view) {
        File file = new File(photoPath);
        file.delete();
        setResult(RESULT_CANCELED);
        finish();
    }
}

`Photo.java`

@Entity(tableName = "photo")
public class Photo {

    @PrimaryKey(autoGenerate = true)
    public int id;

    public String text;

    public String photoPath;

    public Photo(String text, String photoPath) {
        this.text = text;
        this.photoPath = photoPath;
    }
}

`AppDatabase.java`

@Database(entities = {Photo.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {

    private static AppDatabase instance;

    public static synchronized AppDatabase getInstance(Context context) {
        if (instance == null) {
            instance = Room.databaseBuilder(context.getApplicationContext(),
                    AppDatabase.class, "app_database")
                    .build();
        }
        return instance;
    }

    public abstract PhotoDao photoDao();
}

`PhotoDao.java`

@Dao
public interface PhotoDao {

    @Insert
    void insert(Photo photo);

    @Query("SELECT * FROM photo")
    List<Photo> getAll();

    @Delete
    void delete(Photo photo);

    @Query("DELETE FROM photo")
    void deleteAll();
}