How do you get a list of all camera images of an Android devi开发者_开发技巧ce?
Is it through the MediaStore? How?
The Gallery app obtains camera images by using a content resolver over Images.Media.EXTERNAL_CONTENT_URI and filtering the results by Media.BUCKET_ID. The bucket identifier is determined with the following code:
public static final String CAMERA_IMAGE_BUCKET_NAME =
Environment.getExternalStorageDirectory().toString()
+ "/DCIM/Camera";
public static final String CAMERA_IMAGE_BUCKET_ID =
getBucketId(CAMERA_IMAGE_BUCKET_NAME);
/**
* Matches code in MediaProvider.computeBucketValues. Should be a common
* function.
*/
public static String getBucketId(String path) {
return String.valueOf(path.toLowerCase().hashCode());
}
Based on that, here's a snippet to get all camera images:
public static List<String> getCameraImages(Context context) {
final String[] projection = { MediaStore.Images.Media.DATA };
final String selection = MediaStore.Images.Media.BUCKET_ID + " = ?";
final String[] selectionArgs = { CAMERA_IMAGE_BUCKET_ID };
final Cursor cursor = context.getContentResolver().query(Images.Media.EXTERNAL_CONTENT_URI,
projection,
selection,
selectionArgs,
null);
ArrayList<String> result = new ArrayList<String>(cursor.getCount());
if (cursor.moveToFirst()) {
final int dataColumn = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
do {
final String data = cursor.getString(dataColumn);
result.add(data);
} while (cursor.moveToNext());
}
cursor.close();
return result;
}
For more info, review the ImageManager and ImageList classes of the Gallery app source code.
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