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我有一份名单。类似:

ListView.builder(
  key: _listViewKey,
  controller: widget.scrollController,
  shrinkWrap: true,
  scrollDirection: Axis.vertical,
  physics: const AlwaysScrollableScrollPhysics(),
  itemCount: state.items,
  itemBuilder: (context, index) {
  ...

此外,我还拥有使用滚动机打电话囚犯的最终方法。将用户带至名单的底线,而不管其位置如何。这里指的是:

void scrollToEnd() async {
   await Future.delayed(const Duration(milliseconds: 300));
   Future.doWhile(() {
     if (widget.scrollController.positions.last.extentAfter == 0) {
       return Future.value(false);
     }
     return widget.scrollController.animateTo(widget.scrollController.positions.last.maxScrollExtent, duration: Duration(milliseconds: 500), curve: Curves.linear).then((value) => true);
   });
}

我发现,我叫Aimate 仅仅一次,雕刻就足够了,有时是滚动机走到底,因此制定了doWhile方法。

However now when scrolling up the list a few items and evoking scrollToEnd() there seems to be a pretty severe overscroll and total whitespace is shown until eventually the last list items sinks back down into view. I have 2 questions:

Why is widget.scrollController.positions.last.maxScrollExtent ever returning a higher value than the list actually has?
How can I stop this overscroll from happening? My only goal is that scrollToEnd() gets the list to the end every time and that is doesnt look wonky when it does it.

Edit:所有清单项目的高度各异,因此,我需要一种解决办法,即围绕硬编码固定高度开展工作。

Answer 1

如果我正确理解你试图做些什么,也就是要达到名单的结束,那么,我就只是修改了您的<编码>_scrollToEnd的功能,并确保只有在种植花园之后才能使用。

Code

void _scrollToEnd() {
  widget.scrollController.animateTo(
    widget.scrollController.position.maxScrollExtent,
    duration: Duration(milliseconds: 500),
    curve: Curves.linear,
  );
}

Code

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