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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