Android：从gallery保存图像，然后加载到imageview

我有一个onclick，允许用户从gallery中选择一个文件，如下所示：

case R.id.ColourCustom:
                customBorderChange();
                break;

private void customBorderChange() {
    final ImageView QPBackground = (ImageView) findViewById(R.id.QPBackground);
    menuHandler.removeCallbacks(menuTimer);
    menuHandler.postDelayed(menuTimer, 5000);
    bgHandler.removeCallbacks(runnableBG);
    bgHandler.postDelayed(runnableBG, 2000);
    Intent i = new Intent(Intent.ACTION_PICK,
            android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    startActivityForResult(i, GALLERY_REQUEST);
    File file = getFileStreamPath("QuickPlayBG.png");
    if (file.exists()) {
        QPBackground.setImageBitmap(getThumbnail("QuickPlayBG.png"));
    } else {
        String uri21 = "@drawable/bg_green";
        int imageResource21 = getResources().getIdentifier(uri21, null, getPackageName());
        QPBackground.setBackgroundResource(imageResource21);
    }
}

这就把你送到这里：

protected void onActivityResult (int requestCode, int resultCode, Intent data)
{
    Uri selectedImageUri;
    if (requestCode == GALLERY_REQUEST && resultCode == RESULT_OK && null !=
            data) {
        selectedImageUri = data.getData();
        String[] filePathColumn = { MediaStore.Images.Media.DATA };

        Cursor cursor = getContentResolver().query(selectedImageUri,
                filePathColumn, null, null, null);
        cursor.moveToFirst();

        cursor.close();
    }
    try {
        Bundle extras = data.getExtras();
        Bitmap photo = extras.getParcelable("data");
        saveBGFile(photo);
    } catch (Exception e) {
        String errorMessage = "Make your mind up mate!";
        Toast toast = Toast.makeText(this, errorMessage, Toast.LENGTH_SHORT);
        toast.show();
    }
    try {
        saveQPConfig();
    } catch (IOException e) {
        String errorMessage = "Saving failed";
        Toast toast = Toast.makeText(this, errorMessage, Toast.LENGTH_SHORT);
        toast.show();
    }
}

它使用saveBGFile保存文件：

public void saveBGFile(Bitmap image) {
    FileOutputStream out = null;
    String filename = "QuickPlayBG.png";
    try {
        out = new FileOutputStream(filename);
        image.compress(Bitmap.CompressFormat.PNG, 100, out);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (out != null) {
                out.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

问题仅限于这一行：

QPBackground.setImageBitmap(getThumbnail("QuickPlayBG.png"));

它不加载任何内容。如果我将“QuickPlayBG.png”更改为我在应用程序的另一部分中使用的另一个文件名，它将正常加载。这两个文件都是使用相同的方法创建的。我验证了“QuickPlayBG.png”的存在

编译器给了我以下提示：

E/﹕ ReadStreamToBuffer : Qmage Stream read error!! required length 12 bytes, but red 0 bytes
E/﹕ isQmage : input SkStreamRewindable length is less than Qmage minimum size : 0

我认为这与我保存图像的方式有关，但我自己看不到错误。可能是什么问题，它没有加载图像

编辑：

下面是我正在使用的getThumbnail方法（适用于其他文件名）：

---

使用这个简短的代码。画廊的使用意图

1.declaire变量

private static int RESULT_IMG = 1;
String imgString;

2.点击按钮即可调用图库的意图

Intent galleryIntent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(galleryIntent, RESULT_LOAD_IMG);

3.onActivityResult到您的代码

@Override
protected void onActivityResult(int requestCode, int responseCode, Intent data) {
super.onActivityResult(requestCode, responseCode, data);
try {
    if (requestCode == RESULT_IMG && responseCode == RESULT_OK
                    && null != data) {
    Uri pickedImage = data.getData();
    String[] filePathColumn = { MediaStore.Images.Media.DATA };
    Cursor cursor = getContentResolver().query(pickedImage,
            filePathColumn, null, null, null);
    cursor.moveToFirst();
    int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
    imgString = cursor.getString(columnIndex);
    cursor.close();

    //set bitmap to your imageview
    ImageView imgView = (ImageView) findViewById(R.id.imgView);
    imgView.setImageBitmap(BitmapFactory.decodeFile(imgString));
} else {
    Toast.makeText(this, "please select picture",Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
    Toast.makeText(this, "error message", Toast.LENGTH_LONG)
                    .show();
    }
}

@Override
protected void onActivityResult(int requestCode, int responseCode, Intent data) {
super.onActivityResult(requestCode, responseCode, data);
try {
    if (requestCode == RESULT_IMG && responseCode == RESULT_OK
                    && null != data) {
    Uri pickedImage = data.getData();
    String[] filePathColumn = { MediaStore.Images.Media.DATA };
    Cursor cursor = getContentResolver().query(pickedImage,
            filePathColumn, null, null, null);
    cursor.moveToFirst();
    int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
    imgString = cursor.getString(columnIndex);
    cursor.close();

    //set bitmap to your imageview
    ImageView imgView = (ImageView) findViewById(R.id.imgView);
    imgView.setImageBitmap(BitmapFactory.decodeFile(imgString));
} else {
    Toast.makeText(this, "please select picture",Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
    Toast.makeText(this, "error message", Toast.LENGTH_LONG)
                    .show();
    }
}