@Override
public void onPause() {
super.onPause();
// In the case onPause() is called during a fling the image loader is un-paused to let any
// remaining background work complete.
mImageLoader.setPauseWork(false);
}
/**
* Decodes and scales a contact's image from a file pointed to by a Uri in the contact's data, and
* returns the result as a Bitmap. The column that contains the Uri varies according to the
* platform version.
*
* @param photoData provide the Contact.PHOTO_THUMBNAIL_URI value.
* @param imageSize The desired target width and height of the output image in pixels.
* @return A Bitmap containing the contact's image, resized to fit the provided image size. If no
* thumbnail exists, returns null.
*/
private Bitmap loadContactPhotoThumbnail(String photoData, int imageSize) {
// Ensures the Fragment is still added to an activity. As this method is called in a
// background thread, there's the possibility the Fragment is no longer attached and
// added to an activity. If so, no need to spend resources loading the contact photo.
if (!isAdded() || getActivity() == null) {
return null;
}
// Instantiates an AssetFileDescriptor. Given a content Uri pointing to an image file, the
// ContentResolver
// can return an AssetFileDescriptor for the file.
AssetFileDescriptor afd = null;
// This "try" block catches an Exception if the file descriptor returned from the Contacts
// Provider doesn't point to an existing file.
try {
Uri thumbUri;
// Converts the Uri passed as a string to a Uri object.
thumbUri = Uri.parse(photoData);
// Retrieves a file descriptor from the Contacts Provider. To learn more about this
// feature, read the reference documentation for
// ContentResolver#openAssetFileDescriptor.
afd = getActivity().getContentResolver().openAssetFileDescriptor(thumbUri, "r");
// Gets a FileDescriptor from the AssetFileDescriptor. A BitmapFactory object can
// decode the contents of a file pointed to by a FileDescriptor into a Bitmap.
FileDescriptor fileDescriptor = afd.getFileDescriptor();
if (fileDescriptor != null) {
// Decodes a Bitmap from the image pointed to by the FileDescriptor, and scales it
// to the specified width and height
return ImageLoader.decodeSampledBitmapFromDescriptor(fileDescriptor, imageSize, imageSize);
}
} catch (FileNotFoundException e) {
// If the file pointed to by the thumbnail URI doesn't exist, or the file can't be
// opened in "read" mode, ContentResolver.openAssetFileDescriptor throws a
// FileNotFoundException.
if (BuildConfig.DEBUG) {
Log.d(
TAG,
"Contact photo thumbnail not found for contact " + photoData + ": " + e.toString());
}
} finally {
// If an AssetFileDescriptor was returned, try to close it
if (afd != null) {
try {
afd.close();
} catch (IOException e) {
// Closing a file descriptor might cause an IOException if the file is
// already closed. Nothing extra is needed to handle this.
}
}
}
// If the decoding failed, returns null
return null;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Let this fragment contribute menu items
setHasOptionsMenu(true);
// Create the main contacts adapter
mAdapter = new ContactsAdapter(getActivity());
// If we're restoring state after this fragment was recreated then retrieve previous search term
// and previously selected search result.
if (savedInstanceState != null) {
mSearchTerm = savedInstanceState.getString(SearchManager.QUERY);
mPreviouslySelectedSearchItem = savedInstanceState.getInt(STATE_PREVIOUSLY_SELECTED_KEY, 0);
}
/*
* An ImageLoader object loads and resizes an image in the background and binds it to the
* QuickContactBadge in each item layout of the ListView. ImageLoader implements memory
* caching for each image, which substantially improves refreshes of the ListView as the
* user scrolls through it.
*
* To learn more about downloading images asynchronously and caching the results, read the
* Android training class Displaying Bitmaps Efficiently.
*
* http://developer.android.com/training/displaying-bitmaps/
*/
mImageLoader =
new ImageLoader(getActivity(), getListPreferredItemHeight()) {
@Override
protected Bitmap processBitmap(Object data) {
// This gets called in a background thread and passed the data from
// ImageLoader.loadImage().
return loadContactPhotoThumbnail((String) data, getImageSize());
}
};
// Set a placeholder loading image for the image loader
mImageLoader.setLoadingImage(R.drawable.ic_contact_picture_holo_light);
// Add a cache to the image loader
mImageLoader.addImageCache(getActivity().getSupportFragmentManager(), 0.1f);
}
