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Retrieve Picasa Image for Upload from Gallery

I am working on an activity and a开发者_Python百科ssociated tasks that allow users to select an image to use as their profile picture from the Gallery. Once the selection is made the image is uploaded to a web server via its API. I have this working regular images from the gallery. However, if the image selected is from a Picasa Web Album nothing is returned.

I have done a lot of debugging and narrowed the problem down to this method.

public String getPath(Uri uri) {
    String[] projection = { MediaStore.Images.Media.DATA };
    Cursor cursor = managedQuery(uri, projection, null, null, null);
    //cursor is null for picasa images
    if(cursor!=null)
    {
        int column_index = cursor
        .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
    }
    else return null;
}

Picasa images return a null cursor. MediaStore.Images.Media.DATA is not null for them, however. It only returns an #id, so I am guessing that there is no actual bitmap data at the address. Are Picasa images stored locally on the device at all?

I also noticed from the documentation that MediaStore.Images.ImageColumns.PICASA_ID exists. This value exists for selected picasa images but not other gallery images. I was thinking I could use this value to get a URL for the image if it is not store locally but I can not find any information about it anywhere.


I have faced the exact same problem,
Finally the solution I found, was to launch an ACTION_GET_CONTENT intent instead of an ACTION_PICK, then make sure you provide a MediaStore.EXTRA_OUTPUT extra with an uri to a temporary file. Here is the code to start the intent :

public class YourActivity extends Activity {
    File mTempFile;
    int REQUEST_CODE_CHOOSE_PICTURE = 1;

    (...)
    public showImagePicker() { 
        mTempFile = getFileStreamPath("yourTempFile");
        mTempFile.getParentFile().mkdirs();
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT, null);
        intent.setType("image/*");
        intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(mTempFile));
        intent.putExtra("outputFormat",Bitmap.CompressFormat.PNG.name());                       
        startActivityForResult(intent,REQUEST_CODE_CHOOSE_PICTURE);
    }

    (...)
}

You might need to mTempFile.createFile()

Then in onActivityResult, you will be able to get the image this way

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    case REQUEST_CODE_CHOOSE_PICTURE:
                Uri imageUri = data.getData();
                if (imageUri == null || imageUri.toString().length() == 0) {
                    imageUri = Uri.fromFile(mTempFile);
                    file = mTempFile;
                }
                                    if (file == null) {
                                       //use your current method here, for compatibility as some other picture chooser might not handle extra_output
                                    }
}

Hope this helps

Then you should delete your temporary file on finish (it is in internal storage as is, but you can use external storage, I guess it would be better).


Why are you using the managedQuery() method? That method is deprecated.

If you want to convert a Uri to a Bitmap object try this code:

public Bitmap getBitmap(Uri uri) {

    Bitmap orgImage = null;
    try {
        orgImage = BitmapFactory.decodeStream(getApplicationContext().getContentResolver().openInputStream(uri));
    } catch (FileNotFoundException e) {
        // do something if you want
    }
    return orgImage;
}
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