画像をダウンロードして保存しますが、画像ギャラリーは画像を見ることができません

Question

サーバーから画像をダウンロードしてアプリケーションフォルダに配置するギャラリーアプリを作っています。しかし、私はこのアプリ（https://play.google.com/store/apps/details?id=com.sonyericsson.album）を開くと、私は私のダウンロードイメージを見ることができません。これは私のコード ダウンロードの画像です：通知するEnvironment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)

ステップ2. 使用MediaScannerにファイルを保存

private void saveToDirectory(Bitmap bitmap, String path) { 
    File pictureFile = getOutputMediaFile(path); 
    if (pictureFile == null) { 
     Toast.makeText(getActivity(), "Došlo je do greške!", Toast.LENGTH_LONG).show(); 
     Log.d(TAG, 
       "Error creating media file, check storage permissions: ");// e.getMessage()); 
     return; 
    } 
    try { 
     FileOutputStream fos = new FileOutputStream(pictureFile); 
     bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos); 
     fos.close(); 
     Toast.makeText(getActivity(), "Slika je sačuvana!", Toast.LENGTH_LONG).show(); 
    } catch (FileNotFoundException e) { 
     Toast.makeText(getActivity(), "Došlo je do greške!", Toast.LENGTH_LONG).show(); 
     Log.d(TAG, "File not found: " + e.getMessage()); 
    } catch (IOException e) { 
     Toast.makeText(getActivity(), "Došlo je do greške!", Toast.LENGTH_LONG).show(); 
     Log.d(TAG, "Error accessing file: " + e.getMessage()); 
    } 
} 

@Nullable 
private File getOutputMediaFile(String path) { 
    File mediaStorageDir = new File(Environment.getExternalStorageDirectory(), getActivity().getString(R.string.app_name)); 
    Log.d(TAG, mediaStorageDir.getAbsolutePath()); 

    if (!mediaStorageDir.exists()) { 
     if (!mediaStorageDir.mkdirs()) { 
      return null; 
     } 
    } 
    String name = ""; 
    for(int i = path.length() - 1; i >= 0; i--) { 
     if (path.charAt(i) == '/') { 
      break; 
     } 
     name = path.charAt(i) + name; 
    } 

    File mediaFile; 
    String mImageName = getActivity().getString(R.string.app_name) +"_"+ name; 
    //String mImageName = "IMG" +"-"+ name; 
    mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName); 
    return mediaFile; 
} 

Answer 1

、あなたはであるためにギャラリー（あなたのアプリケーションの外部記憶装置）が利用できるようにする必要がありあなたのアプリの外で利用可能です。

https://developer.android.com/training/camera/photobasics.html#TaskGallery

https://developer.android.com/guide/topics/data/data-storage.html#filesExternal

：ドキュメントへ

が

private void galleryAddPic() { 
    Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE); 
    //change mCurrentPhotoPath for your imagepath 
    File f = new File(mCurrentPhotoPath); 
    Uri contentUri = Uri.fromFile(f); 
    mediaScanIntent.setData(contentUri); 
    this.sendBroadcast(mediaScanIntent); 
} 

参考：

、この方法を試してみてください

Answer 2

ステップ1.

：ディレクトリに保存

Glide.with(getActivity()).load(path) 
        .asBitmap() 
        .diskCacheStrategy(DiskCacheStrategy.ALL) 
        .into(new SimpleTarget<Bitmap>() { 
         @Override 
         public void onResourceReady(final Bitmap resource, GlideAnimation<? super Bitmap> glideAnimation) { 
          Log.d(TAG, "pamti se"); 
          new Handler().postDelayed(new Runnable() { 
           @Override 
           public void run() { 
            saveToDirectory(resource, path); 
           } 
          }, 0); 

         } 

        }); 

新しいファイル/イメージに関するシステム。私はそのためのヘルパークラスを作成しました。あなたがしなければならないのは、ファイルパスのパスです：あなたはあなたの内部のアプリのストレージにあなたの画像を保存している

import android.content.Context; 
import android.media.MediaScannerConnection; 
import android.net.Uri; 
import android.support.annotation.NonNull; 
import android.support.annotation.Nullable; 

import java.lang.ref.WeakReference; 

public class MediaScannerUtils implements 
     MediaScannerConnection.MediaScannerConnectionClient { 

    private static final String LOG_TAG = "MediaScannerUtils"; 

    private MediaScannerConnection mConnection; 
    private @Nullable WeakReference<MediaScannerListener> mListenerRef; 
    private String mPathToScan; 
    private String mMimeType; 

    /** 
    * Initialize the MediaScannerUtils class 
    * @param context Any context 
    * @param listener A listener that gets notified when the scan is completed 
    * @param pathToScan The path to scan. If null, the entire sdcard is scanned 
    * @param mimeType The mimeType of files to look for. If null, defaults to "audio/*" 
    */ 
    public MediaScannerUtils(@NonNull Context context, @Nullable MediaScannerListener listener, 
          @Nullable String pathToScan, @Nullable String mimeType) { 
     LogUtils.d(LOG_TAG, "Initializing MediaScannerUtils"); 
     mPathToScan = pathToScan; 
     mMimeType = mimeType; 
     if(pathToScan == null) { 
      //If path to scan is null, set path to the entire SdCard 
      mPathToScan = FileUtils.getSDCardAbsolutePath(); 
     } 
     if(mimeType == null) { 
      //If mime type is null, set mime type to audio wildcard 
      mMimeType = "image/*"; 
     } 

     if(listener != null) { 
      mListenerRef = new WeakReference<>(listener); 
     } 

     mConnection = new MediaScannerConnection(context.getApplicationContext(), this); 
     mConnection.connect(); 
    } 

    /** 
    * Called to notify the client when a connection to the 
    * MediaScanner service has been established. 
    */ 
    public void onMediaScannerConnected() { 
     mConnection.scanFile(mPathToScan, mMimeType); 
    } 

    /** 
    * Called to notify the client when the media scanner has finished 
    * scanning a file. 
    * @param path the path to the file that has been scanned. 
    * @param uri the Uri for the file if the scanning operation succeeded 
    * and the file was added to the media database, or null if scanning failed. 
    */ 
    public void onScanCompleted(String path, Uri uri) { 
     if(mConnection != null) { 
      mConnection.disconnect(); 
     } 

     if(mListenerRef != null) { 
      MediaScannerListener listener = mListenerRef.get(); 
      if (listener != null) { 
       listener.onScanCompleted(); 
      } 
     } 
    } 

    /** 
    * Disconnects the MediaScannerConnection and releases any heavy object 
    */ 
    public void release() { 
     if (mConnection != null) { 
      mConnection.disconnect(); 
      mConnection = null; 
     } 
    } 

    public interface MediaScannerListener { 

     void onScanCompleted(); 

    } 
}