Question

我是新手，要在按下按钮后显示文本小部件。

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<p id="demo"></p>

Answer 1

我不明白您到底想在代码中做什么，但是如果您需要在按下按钮后显示“文本”小部件，只需定义一个bool变量即可检测按钮单击，如下所示：

import 'package:flutter/material.dart';

void main() => runApp(MaterialApp(
      home: MyApp(),
    ));

class MyApp extends StatefulWidget {
  @override
  MyAppState createState() {
    return new MyAppState();
  }
}

class MyAppState extends State<MyApp> {
  bool pressed = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView(
        children: <Widget>[
          pressed ? Text(" text is here ") : SizedBox(),
          RaisedButton(
            child: Text("show text"),
            onPressed: () {
              setState(() {
                pressed = true;
              });
            },
          )
        ],
      ),
    );
  }
}

Answer 2

我是扑朔迷离的新手，想在按下按钮后显示文本小部件。抱歉，我是第一次使用这个平台

  import 'package:flutter/material.dart';
  class dellecturer extends StatefulWidget {
@override
_dellecturerState createState() => _dellecturerState();    }
  class _dellecturerState extends State<dellecturer> {
@override
Widget build(BuildContext context) {
  return Card(
    color: Colors.grey.shade300,
    margin: EdgeInsets.all(10.0),
  child: Container(
    margin: EdgeInsets.all(20),
    child: ListView(
      children: <Widget>[
       new Container(
         margin: EdgeInsets.only(top:13,bottom: 25),
         alignment: Alignment.topCenter,
           child:Text("DELETE BY LECTURER ID",style: TextStyle(color: Colors.redAccent,fontWeight:       FontWeight.bold,fontSize: 20.0),),
       ),
       new TextField(
          decoration:InputDecoration(border: OutlineInputBorder(borderSide: BorderSide(style:       BorderStyle.solid),),labelText: "LECTURER ID",hintText: "Enter       lecturer ID",prefixIcon: Icon(Icons.person)),
        ),
        Padding(padding: EdgeInsets.only(top:20),),
       new RaisedButton(child: Text("OK",style: TextStyle(fontWeight: FontWeight.bold,color: Colors.white,fontSize:     15),),color: Colors.red,onPressed: (){Form(child: Search());},),
      ],
    ),


  ),
  ); 

}    Widget Search(){
setState(() {
return Scaffold(
  body: Container(
  child: ListView(
    children: <Widget>[
      new Text("ID :1234",style: TextStyle(color: Colors.redAccent),),
       new Text("ID :1234",style: TextStyle(color: Colors.redAccent),),
        new Text("ID :1234",style: TextStyle(color: Colors.redAccent),),
    ],
  ),
  )
);
});
  }    }
  **

Flutter代码，要在按下按钮时添加或显示小部件，或者在按下方法时设置状态

2 个答案: