dispose method
Disposes the data source. This should not be called directly. DataSource is disposed automatically when no longer needed for clipboard or drag and drop by ClipboardWriter and DragContext.
Implementation
Future<void> dispose() async {
if (!_disposed) {
_disposed = true;
_onDispose.notify();
_onDispose.dispose();
await DataProviderManager.instance.unregisterDataProvider(id);
}
}