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Question

我尝试在ListView中运行包含Gridview的代码

      body: ListView(
        shrinkWrap: true,
        children: <Widget>[
          Stack(
            children: <Widget>[
              Container(
                alignment: Alignment(0.0, -0.40),
                height: 100.0,
                color: Colors.white,
                child: Text(
                  'أحصل على تدريب',
                  style: TextStyle(fontFamily: 'Janna', fontSize: 20.0),
                ),
              ),
              Container(
                margin: EdgeInsets.fromLTRB(25.0, 90.0, 25.0, 0.0),
                decoration: BoxDecoration(
                    color: Colors.white,
                    borderRadius: BorderRadius.circular(20.0),
                    boxShadow: [
                      BoxShadow(
                        blurRadius: 2.0,
                        color: Colors.grey,
                      )
                    ]),
                child: Row(
                  crossAxisAlignment: CrossAxisAlignment.center,
                  children: <Widget>[
                    Stack(
                      children: <Widget>[
                        Container(
                          padding: EdgeInsets.fromLTRB(25.0, 25.0, 35.0, 25.0),
                          child: Text(
                            'لديك',
                            style: TextStyle(
                                fontFamily: 'Janna',
                                color: Colors.grey,
                                fontWeight: FontWeight.bold,
                                fontSize: 16.0),
                          ),
                        ),
                        Container(
                          padding: EdgeInsets.fromLTRB(25.0, 50.0, 25.0, 25.0),
                          child: Text(
                            '200',
                            style: TextStyle(
                                fontFamily: 'Janna',
                                color: Colors.black,
                                fontWeight: FontWeight.bold,
                                fontSize: 30.0),
                          ),
                        ),
                      ],
                    ),
                    SizedBox(
                      width: 100,
                    ),
                    Container(
                      height: 50,
                      width: 120,
                      decoration: BoxDecoration(
                        color: Colors.greenAccent[100].withOpacity(0.7),
                        borderRadius: BorderRadius.circular(10.0),
                      ),
                      child: Center(
                        child: Text(
                          'إشتري المزيد',
                          style: TextStyle(
                              fontFamily: 'Janna',
                              color: Colors.green,
                              fontWeight: FontWeight.bold,
                              fontSize: 15.0),
                        ),
                      ),
                    ),
                  ],
                ),
              )
            ],
          ),
          SizedBox(
            height: 40.0,
          ),
          Container(
            padding: EdgeInsets.only(left: 25.0, right: 25.0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: <Widget>[
                Text(
                  'المدربين',
                  style: TextStyle(
                      fontFamily: 'Janna',
                      color: Colors.grey,
                      fontWeight: FontWeight.bold,
                      fontSize: 14.0),
                ),
                Text(
                  'أظهر الجلسات السابقة',
                  style: TextStyle(
                      fontFamily: 'Janna',
                      color: Colors.green,
                      fontWeight: FontWeight.bold,
                      fontSize: 14.0),
                ),
              ],
            ),
          ),
          SizedBox(
            height: 20.0,
          ),
          GridView.count(
            shrinkWrap: true,
            physics: ClampingScrollPhysics(),
            crossAxisCount: 2, // Number of Cards in each Row
            primary: false,
            crossAxisSpacing: 4.0, // Space between Cards
            mainAxisSpacing: 4.0, // Space between Rows

            children: <Widget>[
              _buildCard('فدوى', 'متوفر', 1,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
              _buildCard('فدوى', 'متوفر', 2,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
              _buildCard('فدوى', 'متوفر', 3,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
              _buildCard('فدوى', 'متوفر', 4,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
              _buildCard('فدوى', 'متوفر', 5,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
              _buildCard('فدوى', 'متوفر', 6,
                  'https://i.pinimg.com/originals/64/ce/92/64ce9246abec3f86b7d5a8d2a562a03c.jpg'),
            ],
          )
        ],
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }

  Widget _buildCard(String name, String status, int cardIndex, String img) {
    return Card(
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.0)),
      elevation: 7.0,
      child: Column(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: <Widget>[
          SizedBox(
            height: 12.0,
          ),
          Container(
            child: Column(
              children: <Widget>[
                Stack(
                  children: <Widget>[
                    CircleAvatar(
                      radius: 35.0,
                      backgroundImage: NetworkImage(img),
                    ),
                    Container(
//                      padding: EdgeInsets.fromLTRB(0, 0, 0, 0),
                      child: CircleAvatar(
                        radius: 10.0,
                        backgroundColor: Colors.white,
                        child: CircleAvatar(
                          radius: 6.0,
                          backgroundColor:
                              status == 'بعيد' ? Colors.grey : Colors.green,
                        ),
                      ),
                    ),
                  ],
                ),
                SizedBox(
                  height: 8.0,
                ),
                Text(
                  status,
                  style: TextStyle(
                      fontFamily: 'Janna',
                      fontSize: 14.0,
                      fontWeight: FontWeight.bold,
                      color: Colors.grey),
                ),
              ],
            ),
          ),
          Container(
            padding: EdgeInsets.all(7.0),
            width: double.infinity,
            decoration: BoxDecoration(
              color: status == 'بعيد' ? Colors.grey : Colors.green,
              borderRadius: BorderRadius.only(
                bottomLeft: Radius.circular(10.0),
                bottomRight: Radius.circular(10.0),
              ),
            ),
            child: Center(
              child: Text(
                'طلب',
                style: TextStyle(
                  fontSize: 20.0,
                  fontFamily: 'Janna',
                  fontWeight: FontWeight.bold,
                  color: Colors.white,
                ),
              ),
            ),
          )
        ],
      ),
      margin: cardIndex.isEven
          ? EdgeInsets.fromLTRB(25.0, 0.0, 5.0, 10.0)
          : EdgeInsets.fromLTRB(10.0, 0.0, 25.0, 10.0),
    );
  }
}

每次我得到这个错误，不管我改变了什么。

╞═════════════════════════════════════════════════════════i/

( 9523)：呈现库performResize I/flutter (9523)捕获的══╡异常:在performResize()：I/flutter (9523)期间抛出以下断言:垂直视图被赋予无限高。I/颤振( 9523)：视图在滚动方向展开以填充它们的容器。在这种情况下，垂直I/颤振( 9523)：viewport被给予无限的垂直空间来扩展。这种情况I/flutter ( 9523)：通常发生在可滚动小部件嵌套在另一个可滚动小部件中时。I/flutter ( 9523)：如果这个小部件总是嵌套在一个可滚动的小部件中，那么就不需要使用视口了，因为I/flutter ( 9523)：将始终有足够的垂直空间供子部件使用。在这种情况下，可以考虑使用列I/颤振( 9523)：代替。否则，考虑使用"shrinkWrap“属性(或.

)

Answer 1

我也试过你的最小复制，它看起来很好。正如注释中提到的，您可以尝试运行flutter clean然后运行flutter run。此问题可能是由未包含在构建中的代码更改造成的。

如果未定义父部件高度，则通常会导致错误"Vertical viewport was given unbounded height"。这将导致ListView的高度无限，ListView需要定义其高度。