错误 hasSize 即使有扩展并且有容器高度和宽度答案

【问题标题】：Error hasSize even though there is expanded and there is container height and width错误 hasSize 即使有扩展并且有容器高度和宽度
【发布时间】：2023-01-16 17:11:06
【问题描述】：

我对下面的代码有疑问

Align(
 alignment: Alignment.center,
 child:Expanded(
 child: Container(
 decoration: AppDecoration.fillGray100.copyWith(
 borderRadius: BorderRadiusStyle.roundedBorder16,
 ),
 child: Expanded(
 child: Column(
 children: [
 Expanded(
 child: Row(
 children: [
 Container(
 padding: getPadding(
 all: 12,
 ),
 decoration: AppDecoration.fillGray100,
 child: Expanded(
 child: Row(
 children: [
 Expanded(
 child: Column(
 mainAxisAlignment:
 MainAxisAlignment.start,
 children: [
 CustomImageView(
 svgPath:
 ImageConstant.imgSearch,
 height: getSize(
 24.00,
 ),
 width: getSize(
 24.00,
 ),
 margin: getMargin(
 all: 12,
 ),
 ),
 ],
 ),
 ),
 ],
 ),
 ),
 ),
 AppbarTitle(
 text: "lbl_search_doctor".tr,
 margin: getMargin(
 left: 16,
 top: 14,
 right: 125,
 bottom: 14,
 ),
 ),
 ],
 ),
 ),
 ],
 ),
 ),
 ),
 ),
 ),

错误信息： 'package:flutter/src/rendering/shifted_box.dart'：断言失败：第 361 行 pos 12：'child!.hasSize'：不正确。

RenderBox 未布局：RenderDecoratedBox#79ea0 relayoutBoundary=up2 '包：flutter/src/rendering/box.dart'：断言失败：第 2001 行第 12 行：'hasSize'

这是错误消息，此代码之前没有单个滚动视图

【问题讨论】：

标签： flutter

【解决方案1】：

您在两个地方错误地使用了 Expanded 。第一个在容器上方，第二个在列上方。这导致它们具有无限的宽度和高度。我修改了代码：-

Align(
alignment: Alignment.center,
child: Container(
decoration: AppDecoration.fillGray100.copyWith(
  borderRadius: BorderRadiusStyle.roundedBorder16,
),
child: Column(
  children: [
    Row(
      children: [
        Container(
          padding: getPadding(
            all: 12,
          ),
          decoration: AppDecoration.fillGray100,
          child: Expanded(
            child: Row(
              children: [
                Expanded(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.start,
                    children: [
                      CustomImageView(
                        svgPath: ImageConstant.imgSearch,
                        height: getSize(
                          24.00,
                        ),
                        width: getSize(
                          24.00,
                        ),
                        margin: getMargin(
                          all: 12,
                        ),
                      ),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
        AppbarTitle(
          text: "lbl_search_doctor".tr,
          margin: getMargin(
            left: 16,
            top: 14,
            right: 125,
            bottom: 14,
          ),
        ),
      ],
    ),
  ],
),
),
),

【讨论】：