Question

我是扑扑的新手，我只是学习扑扑的所有基本知识。我遇到了按钮小部件并按下了功能，然后创建了一个简单的容器，里面有一个这样的按钮

这是容器

Container(

    child: Padding(
    padding: const EdgeInsets.only(top: 25.0, left: 30),
    child: Text("Item 1", style: TextStyle(
    color: Colors.lightBlueAccent,
    fontWeight: FontWeight.bold,
    fontSize: 20,
            ),
           ),
          ),

这是按钮

child: FloatingActionButton(

     onPressed(){},
    child: Text("+", style: TextStyle(
    fontSize: 20,
                 ),
                ),
    backgroundColor: Colors.lightBlue,

               ),

并且我想使按钮具有将容器背景更改为某种颜色（例如蓝色）的功能。但是我想我似乎无法在互联网上找到答案。有什么我可以应用的方法或我不知道存在的代码？

提前谢谢！

Answer 1

声明默认材料颜色

fetch

在onPressed（）内更改上述颜色

push

Answer 2

尽管您仍然从jitsm555得到了一个很棒的答案，但这是完整的示例，我希望它可以为您提供进一步的帮助。


import 'package:flutter/material.dart';

void main() {
  runApp(ColorChange());
}

class ColorChange extends StatefulWidget {
  @override
  _ColorChangeState createState() => _ColorChangeState();
}

class _ColorChangeState extends State<ColorChange> {
  //Initially color is set to yellow which will be changed when button is pressed
  Color color = Colors.yellow;
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text("Change Container Color"),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              Container(
                width: 300,
                height: 300,
                color: color, //value of color which we will change by pressing buttons
              ),

             /* Below Row of Button when pressed will fire up 
                the setState and the state of our default color variable will 
                change according to Button which is pressed
             */
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  RaisedButton(
                    color: Colors.red,
                    child: Text("Red"),
                    onPressed: () {
                      setState(() {
                        color = Colors.red;
                      });
                    },
                  ),
                  RaisedButton(
                    color: Colors.green,
                    child: Text("Green"),
                    onPressed: () {
                      setState(() {
                        color = Colors.green;
                      });
                    },
                  ),
                  RaisedButton(
                    color: Colors.blue,
                    child: Text("Blue"),
                    onPressed: () {
                      setState(() {
                        color = Colors.blue;
                      });
                    },
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }
}

输出：

可以更改容器背景颜色/颤动颜色的按钮

2 个答案: