Flutter RenderObject 断言失败

Question

我遇到以下错误：

======== Exception caught by scheduler library =====================================================
The following assertion was thrown during a scheduler callback:
Updated layout information required for RenderIndexedSemantics#f51aa NEEDS-LAYOUT to calculate semantics.
'package:flutter/src/rendering/object.dart':
Failed assertion: line 2658 pos 12: '!_needsLayout'


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=2_bug.md

When the exception was thrown, this was the stack: 
#2      RenderObject._getSemanticsForParent (package:flutter/src/rendering/object.dart:2658:12)
#3      RenderObject._getSemanticsForParent.<anonymous closure> (package:flutter/src/rendering/object.dart:2680:61)
#4      Iterable.forEach (dart:core/iterable.dart:257:30)
#5      RenderSliverVariableSizeBoxAdaptor.visitChildren (package:flutter_staggered_grid_view/src/rendering/sliver_variable_size_box_adaptor.dart:296:29)
#6      RenderObject.visitChildrenForSemantics (package:flutter/src/rendering/object.dart:2765:5)
...
====================================================================================================

我想知道这是什么意思，这通常发生在什么时候？
我正在使用 flutter_staggered_grid_view: ^0.4.0 package.

如果需要，我会创建一个 GitHub 问题。

编辑：这是一段突出问题的代码：

我的主要 Widget 由 :

呈现

StaggeredGridView.countBuilder(
      itemBuilder: (BuildContext context, int index) {
        return MyCustomItem();
      },
      padding: EdgeInsets.only(left: Constants.maxWidth*2/100, right: Constants.maxWidth*2/100,
          bottom: Constants.maxHeight*10/100 + 65), // home button size + margin bottom
      crossAxisCount: 2,
      mainAxisSpacing: 20,
      crossAxisSpacing: Constants.maxWidth*2/100,
      itemCount: 30,
      physics: BouncingScrollPhysics(),
      staggeredTileBuilder: (int index) {
        return StaggeredTile.fit(1);
      },
    ),

和 MyCustomItem 组成列表中每个项目的小部件：

Column(
      children: [
        GestureDetector(
          child:
          Container(
            margin: (widget.index == 0 || widget.index == 1) ? EdgeInsets.only(top: Constants.maxHeight*6/100+60) : EdgeInsets.all(0),
            //width: postWidth,
            // TODO : post height
            child: ClipRRect(
              borderRadius: BorderRadius.all(Radius.circular(20)),
              child: Image.asset("assets/images/test.jpg"), // TODO 
            ),
          ),
          onTap: () {
            // TODO
          },
          onDoubleTap: () {
            // TODO
          },
        ),
        Row(
          children: [
            Column(
              crossAxisAlignment: CrossAxisAlignment.center,
              mainAxisSize: MainAxisSize.min,
              children: [
                GestureDetector(child:
                Container(
                  margin: EdgeInsets.only(top: 10, bottom: 3),
                  width: 35,
                  height: 35,
                ),
                  onTap: () {
                    // TODO 
                  },
                ),
                Flexible(child:
                Container(
                  width: Constants.maxWidth*25/100,
                  child:
                  Text(
                    "tessssst",
                    textAlign: TextAlign.center,
                    overflow: TextOverflow.ellipsis,
                    style: TextStyle(
                      fontSize: 14,
                      fontWeight: FontWeight.bold,
                      color: Color(resColors.getShadow()),
                    ),
                    maxLines: 1,
                  ),
                ),
                ),
              ],
            ),
            Spacer(),
            Container(
              margin: EdgeInsets.only(right: Constants.maxWidth * 2 / 100),
              child: Column(children: [
                Container(
                  margin: EdgeInsets.only(bottom: 3, top: 10),
                  child: InkWell(
                    onTap: () {
                      // TODO
                    },
                    highlightColor: Colors.transparent,
                    splashColor: Colors.transparent,
                  ),
                ),
                Text("1029"),
              ]),
            ),
            Container(
              child: Column(children: [
                Container(
                  margin: EdgeInsets.only(bottom: 3, top: 10, right: Constants.maxWidth/100),
                  child: InkWell(
                    onTap: () => {},// TODO
                    highlightColor: Colors.transparent,
                    splashColor: Colors.transparent,
                  ),
                ),
                Text("Test"),
              ]),
            ),
          ],
        )
      ],
    );

我要补充一点，如果 MyCustomItem 只是一个 Text 小部件，我没有错误。

Answer 1

您现在可以使用目前正在测试的 flutter_staggered_grid_view 存储库的新 branch，但它已经为我解决了这个问题。

所有者表示这是插件的完整重构，修复了许多错误。

Flutter RenderObject 断言失败

Flutter RenderObject assertion failure

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