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Flutter 如何在列表上方添加按钮?_Flutter_Dart_Flutter Layout_Flutter Listview - Fatal编程技术网

Flutter 如何在列表上方添加按钮?

Flutter 如何在列表上方添加按钮?,flutter,dart,flutter-layout,flutter-listview,Flutter,Dart,Flutter Layout,Flutter Listview,我试图在列表视图上方添加一个RaisedButton。我用了一个column,但我出错了。有人能告诉我我的错误在哪里吗?提前谢谢 body: Column( children: <Widget>[ RaisedButton( child: Text("Test"), onPressed: null, ), ListView.builder(

我试图在
列表视图
上方添加一个
RaisedButton
。我用了一个
column
,但我出错了。有人能告诉我我的错误在哪里吗?提前谢谢

 body: Column(
        children: <Widget>[
          RaisedButton(
            child: Text("Test"),
            onPressed: null,
          ),
          ListView.builder(
            itemCount: exercises.length,
            itemBuilder: (context, i) {
              return Container(
                child: Text(
                  exercises[i]["text"],
                ),
              );
            },
          ),
        ],
      ),
body:Column(
儿童:[
升起的按钮(
子项:文本(“测试”),
onPressed:null,
),
ListView.builder(
itemCount:exercises.length,
itemBuilder:(上下文,i){
返回容器(
子:文本(
练习[i][“文本”],
),
);
},
),
],
),

您需要用扩展的小部件包装listview

     body: Column(
    children: <Widget>[
      RaisedButton(
        child: Text("Test"),
        onPressed: null,
      ),
      Expanded( // added widget
     child: ListView.builder(
        itemCount: exercises.length,
        itemBuilder: (context, i) {
          return Container(
            child: Text(
              exercises[i]["text"],
            ),
          );
        },
      ),
    ],
  ),
  )
body:Column(
儿童:[
升起的按钮(
子项:文本(“测试”),
onPressed:null,
),
扩展的(//添加的小部件
子项:ListView.builder(
itemCount:exercises.length,
itemBuilder:(上下文,i){
返回容器(
子:文本(
练习[i][“文本”],
),
);
},
),
],
),
)

添加到@Viren answer中,您应该使用灵活的而不是扩展的

body: Column(
        children: <Widget>[
          RaisedButton(
            child: Text("Test"),
            onPressed: null,
          ),
          Flexible(
            child: Container(
              child: ListView.builder(
                itemCount: 5,
                itemBuilder: (context, i) {
                  return Container(
                    child: Text(
                      'jitesh',
                    ),
                  );
                },
              ),
            ),
          )
        ],
      ),
body:Column(
儿童:[
升起的按钮(
子项:文本(“测试”),
onPressed:null,
),
灵活的(
子:容器(
子项:ListView.builder(
物品计数:5,
itemBuilder:(上下文,i){
返回容器(
子:文本(
“吉特什”,
),
);
},
),
),
)
],
),
请查找差异