ios 运行不起来

[wujiegoodluck]

Compiler message:
file:///Users/wujie/.pub-cache/hosted/pub.flutter-io.cn/pull_to_refresh-1.1.5/lib/src/internals/indicator_wrap.dart:105:46: Error: The argument type 'Null Function(Null)' can't be assigned to the parameter type 'dynamic Function(void)'.
Try changing the type of the parameter, or casting the argument to 'dynamic Function(void)'.
_sizeController.animateTo(minSpace).then((Null val) {