flutter - 我怎样才能像 child 一样使用 CustomScrollView

Question

我是一个刚接触 Flutter 的新手。

我想使用 CustomScrollView 作为 Row/Column Widget 的子级

当 CustomScrollView 是 root 时，它工作得很好。但是，一旦我将它放入 Row Widget 的子项中，它就会报错。

不能将 CustomScrollview 用作 Row 小部件的子项吗？如果是，请告诉我原因，最好的选择是什么？

或者，如果我的代码有错误，我希望你能更正它。

What I want to make

my CustomScrollViewWidget

我不知道这是不是你想要的，但这是我的错误。

══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
The following assertion was thrown during performLayout():
'package:flutter/src/rendering/viewport.dart': Failed assertion: line 1758 pos 16:
'constraints.hasBoundedHeight': is not true.
Either the assertion indicates an error in the framework itself, or we should provide substantially
more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
  https://github.com/flutter/flutter/issues/new?template=BUG.md
The relevant error-causing widget was:
  CustomScrollView



The following RenderObject was being processed when the exception was fired: RenderShrinkWrappingViewport#0344f relayoutBoundary=up14 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE:
  needs compositing
  creator: ShrinkWrappingViewport ← IgnorePointer-[GlobalKey#e4530] ← Semantics ← _PointerListener ←
    Listener ← _GestureSemantics ←
    RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#a61b3] ← _PointerListener ← Listener
    ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#42b3c] ← RepaintBoundary ← ⋯
  parentData: <none> (can use size)
  constraints: BoxConstraints(unconstrained)
  size: MISSING
  axisDirection: right
  crossAxisDirection: down
  offset: ScrollPositionWithSingleContext#46fe1(offset: 0.0, range: null..null, viewport: null,
    ScrollableState, ClampingScrollPhysics -> RangeMaintainingScrollPhysics, IdleScrollActivity#66c28,
    ScrollDirection.idle)
This RenderObject had the following child:
    child 0: RenderSliverList#42dfb NEEDS-LAYOUT NEEDS-PAINT
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderShrinkWrappingViewport#0344f relayoutBoundary=up14 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1702 pos 12: 'hasSize'
The relevant error-causing widget was
CustomScrollView
lib\0. TestCode.dart:31
════════════════════════════════════════════════════════════════════════════════

这是我的代码!

class WrapVisit extends StatefulWidget {
  WrapVisitState createState() => WrapVisitState();
}

class WrapVisitState extends State<WrapVisit> {
  @override
  Widget build(BuildContext context) {
    return new Container(
      padding: EdgeInsets.all(10),
      color: Colors.white,
      child: Column(
        children: [
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              new Text(
                "브랜드관",
                textAlign: TextAlign.left,
                style: TextStyle(fontWeight: FontWeight.bold),
              ),
              new Container(
                margin: EdgeInsets.all(5),
                child: new Text(
                  "전체보기",
                  textAlign: TextAlign.right,
                  style: TextStyle(
                    fontSize: 10,
                    color: Colors.black,
                  ),
                ),
              ),
              CustomScrollView(
                shrinkWrap: true,
                scrollDirection: Axis.horizontal,
                slivers: [
                  SliverList(
                    delegate: SliverChildListDelegate(
                      [
                        ... SliverListChildWidgets ...
                      ],
                    ),
                  ),
                ],
              ),
            ],
          ),
        ],
      ),
    );
  }
}

Answer 1

Column 不喜欢无限制高度的 child 。要修复它，请将 CustomScrollView 的 shr​​inkWrap 参数设置为 true。