您将需要编写Content Providers以在内部存储中共享图像
请参阅共享存储在内存中的图像
public class MediaContentProvider extends ContentProvider {
private static final String TAG = "MediaContentProvider";
// name for the provider class
public static final String AUTHORITY = "com.way.srl.HandyWay.contentproviders.media";
private MediaData _mediaData;
// UriMatcher used to match against incoming requests
private UriMatcher _uriMatcher;
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
// TODO Auto-generated method stub
return 0;
}
@Override
public String getType(Uri uri) {
// TODO Auto-generated method stub
return null;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
// TODO Auto-generated method stub
return null;
}
@Override
public boolean onCreate() {
uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
// Add a URI to the matcher which will match against the form
// 'content://com.stephendnicholas.gmailattach.provider/*'
// and return 1 in the case that the incoming Uri matches this pattern
_uriMatcher.addURI(AUTHORITY, "*", 1);
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
// TODO Auto-generated method stub
return null;
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
// TODO Auto-generated method stub
return 0;
}
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
Log.v(TAG, "Called with uri: '" + uri + "'." + uri.getLastPathSegment());
// Check incoming Uri against the matcher
switch (_uriMatcher.match(uri)) {
// If it returns 1 - then it matches the Uri defined in onCreate
case 1:
// The desired file name is specified by the last segment of the
// path
// E.g.
// 'content://com.stephendnicholas.gmailattach.provider/Test.txt'
// Take this and build the path to the file
// String fileLocation = getContext().getCacheDir() + File.separator + uri.getLastPathSegment();
Integer mediaID = Integer.valueOf(uri.getLastPathSegment());
if (_mediaData == null) {
_mediaData = new MediaData();
}
Media m = _mediaData.get(mediaID);
// Create & return a ParcelFileDescriptor pointing to the file
// Note: I don't care what mode they ask for - they're only getting
// read only
ParcelFileDescriptor pfd = ParcelFileDescriptor.open(new File(m.filePath), ParcelFileDescriptor.MODE_READ_ONLY);
return pfd;
// Otherwise unrecognised Uri
default:
Log.v(TAG, "Unsupported uri: '" + uri + "'.");
throw new FileNotFoundException("Unsupported uri: " + uri.toString());
}
}