flutter-animatedlist

来源： https://stackoverflow.com/questions/54376420/how-to-update-data-in-an-animatedlist-in-flutter

问题 I am using Animated List in flutter to load a list class, while adding or removing the items, the animation works but when the list is initially loaded, the animation does not work. Is there a way to animate items when initially loading the list. class AnimationTest extends StatefulWidget { @override _AnimationTestState createState() => _AnimationTestState(); } class _AnimationTestState extends State<AnimationTest> with SingleTickerProviderStateMixin { AnimationController _controller;

问题 I was trying to preproduce all of the update operations on an AnimatedList like I have done for a RecyclerView adapter in Android. But when I got to clearing all of the data, I couldn't figure out how to do it. If I do this setState(() { _data.clear(); }); then the backing data is cleared but the GlobalKey's current state still doesn't know about the change, and there is no clear() method on it. Supplemental code import 'package:flutter/material.dart'; void main() => runApp(MyApp()); class

问题 All examples I have found of inserting items into a Flutter AnimatedList utilize a GlobalKey.currentState to tell the AnimatedList widget that an item has been inserted. Same thing with delete from the list. It is known that in Flutter a GlobalKey's currentState may be null. In my case, I am waiting on a Firebase message to come through. When it appears that message is inserted into the AnimatedList's List data and if one were to follow the prevalent examples shown for AnimatedList one would