android 二维码保存成功了，但是微信从相册里找二维码找不到？保存对象是bitmap

Glide.with(getApplicationContext()).load(mUrl).asBitmap().into(new SimpleTarget<Bitmap>() {
@Override
public void onResourceReady(Bitmap resource, GlideAnimation<? super Bitmap> glideAnimation) {
bmp = resource;
iv_wechat_code.setScaleType(ImageView.ScaleType.CENTER_CROP);
iv_wechat_code.setImageBitmap(bmp);
}
});

private void showSave() {

new Thread(saveFileRunnable).start();
}

/***********************************************************/
/**
* 保存照片
*
* @param bm
* @param fileName
* @throws IOException
*/
private final static String ALBUM_PATH = Environment.getExternalStorageDirectory() + "/abcd/";
private String mSaveMessage;
private String fileName="android.jpg";

public void saveFile(Bitmap bm) throws IOException {
File dirFile = new File(ALBUM_PATH);
if (!dirFile.exists()) {
dirFile.mkdir();
}
File myCaptureFile = new File(ALBUM_PATH + fileName);
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(myCaptureFile));
bm.compress(Bitmap.CompressFormat.JPEG, 80, bos);

PS:红色部分不加的话，哼哼，。。。那是更新图库的，不然微信找不到哈
Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
Uri uri = Uri.fromFile(myCaptureFile);
intent.setData(uri);
sendBroadcast(intent);

bos.flush();
bos.close();
}

private Runnable saveFileRunnable = new Runnable() {
@Override
public void run() {
try {
saveFile(bmp);
mSaveMessage = "图片保存成功！";
} catch (IOException e) {
mSaveMessage = "图片保存失败！";
e.printStackTrace();
}
messageHandler.sendMessage(messageHandler.obtainMessage());
}

};

private Handler messageHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (mLoading != null) mLoading.dismiss();
Log.d("tag", mSaveMessage);

ToastUtils.showShort2(WeichatCodeActivity.this,mSaveMessage);
}
};
/***********************************************************/