要将相机拍摄的照片保存到特定文件夹并在设备画廊中查看,可以按照以下步骤进行操作:
import android.content.ContentValues;
import android.content.Intent;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
public class MainActivity extends AppCompatActivity {
    private static final int CAMERA_REQUEST_CODE = 1;
    private File imageFile;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button captureButton = findViewById(R.id.capture_button);
        captureButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                capturePhoto();
            }
        });
    }
    private void capturePhoto() {
        Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        if (cameraIntent.resolveActivity(getPackageManager()) != null) {
            // 创建保存照片的文件
            imageFile = createImageFile();
            // 将照片保存到文件中
            if (imageFile != null) {
                Uri photoUri = FileProvider.getUriForFile(this,
                        "com.example.android.fileprovider",
                        imageFile);
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoUri);
                startActivityForResult(cameraIntent, CAMERA_REQUEST_CODE);
            }
        }
    }
    private File createImageFile() {
        // 创建一个文件名
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(new Date());
        String imageFileName = "IMG_" + timeStamp + ".jpg";
        // 获取存储照片的文件夹
        File storageDir = new File(Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES), "MyApp");
        // 如果文件夹不存在,则创建文件夹
        if (!storageDir.exists()) {
            storageDir.mkdirs();
        }
        // 创建保存照片的文件
        File imageFile = new File(storageDir, imageFileName);
        return imageFile;
    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == CAMERA_REQUEST_CODE && resultCode == RESULT_OK) {
            // 将照片添加到设备的图库中
            Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
            Uri contentUri = Uri.fromFile(imageFile);
            mediaScanIntent.setData(contentUri);
            this.sendBroadcast(mediaScanIntent);
        }
    }
}
file_paths.xml,放在res/xml文件夹下,内容如下:
     
    ...
    
         
 
现在,当用户点击拍照按钮时,将会启动相机应用程序,拍摄完照片后,照片将保存在指定文件夹中,并在设备的画廊中可见。