經過自己整理，思路來自 stormzhang 的博文

目的是將圖片儲存到自定義目錄下，並在系統圖庫中展示

一、儲存圖片到自定義路徑

通常情況下，我們對儲存圖片的處理是這樣的：

public static File saveImage(Bitmap bmp) {
    File appDir = new File(Environment.getExternalStorageDirectory(), "SelfDefine");
    if (!appDir.exists()) {
        appDir.mkdir();    //建立資料夾
    }
    String fileName = System.currentTimeMillis() + ".jpg"; //需要的圖片格式
    File file = new File(appDir, fileName);
    try {
        FileOutputStream fos = new FileOutputStream(file); //獲取檔案流
        bmp.compress(CompressFormat.JPEG, 100, fos);  //儲存成圖片
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}
 

這樣，圖片就被儲存到了/sdcard/SelfDefine/路徑下了

二、將圖片插入系統圖庫並更新

<code class="language-ruby" data-lang="ruby"><span class="no">MediaStore</span><span class="o">.</span><span class="n">Images</span><span class="o">.</span><span class="n">Media</span><span class="o">.</span><span class="n">insertImage</span><span class="p">(</span><span class="n">getContentResolver</span><span class="p">(),</span> <span class="n">bitmap</span><span class="p">,</span> <span class="s2">"title"</span><span class="p">,</span> <span class="s2">"description"</span><span class="p">);</span></code>
 

MediaStore.Images.Media.insertImage(getContentResolver(), "image path", "title", "description");

注意，以上方法不會更新相簿，需要手工再去更新相簿，才可以將圖片顯示在相簿中。

更新相簿方法如下：

1、廣播掃描SD卡，掃描中不能訪問SD卡，體驗不好

sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));

sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.fromFile(new File("/sdcard/SelfDefine/image.jpg"))););

final MediaScannerConnection msc = new MediaScannerConnection(mContext, new MediaScannerConnectionClient() {     
    public void onMediaScannerConnected() {     
        msc.scanFile("/sdcard/SelfDefine/image.jpg", "image/jpg");     
    }     
    public void onScanCompleted(String path, Uri uri) {     
        Log.v(TAG, "scan completed");     
        msc.disconnect();     
    }     
});

三、兩者結合的終極方法

public static void saveImageToGallery(Context context, Bitmap bmp) {
    // 首先儲存圖片
    File appDir = new File(Environment.getExternalStorageDirectory(), "Boohee");
    if (!appDir.exists()) {
        appDir.mkdir();
    }
    String fileName = System.currentTimeMillis() + ".jpg";
    File file = new File(appDir, fileName);
    try {
        FileOutputStream fos = new FileOutputStream(file);
        bmp.compress(CompressFormat.JPEG, 100, fos);
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
	}
    
    // 其次把檔案插入到系統圖庫
    try {
        MediaStore.Images.Media.insertImage(context.getContentResolver(),
				file.getAbsolutePath(), fileName, null);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    // 最後通知相簿更新
    context.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://" + path)));
}