目录

前言

需求

实现

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前言

最近闲着无聊学习了flutter的一下知识，发现flutter和安卓之间，页面开发的方式还是有较大的差异的，众所周知，android的页面开发都是写在xml文件中的，而flutter直接写在代码里（dart文件中），从目前我的认识来看，两者在UI上的“套娃”方式，flutter更能套，简直就是“套中套”啊哈哈。比如今天的手写一个最简单的自定义按钮吧，效果如下图所示

需求

• 带文本的普通按钮，可修改字体大小和字体颜色
• 提供修改背景色，按下后的背景色支持
• 支持圆角和边框
• 提供点击事件的回调

 这几个需求还是毕竟常用的，目前没考虑渐变色和图标，具体需求具体改吧

实现

本次demo的代码本身属于练手，相当于flutter的"hello world"(毕竟我才刚了解flutter没几天）。

以下是具体的代码实现：

import 'package:flutter/material.dart';

class CustomTextButton extends StatefulWidget {
  //按钮的宽度
  final double? width;
  //按钮的长度
  final double? height;
  final String text;
  final double? textSize;
  final Color textColor;
  final Color backgroundColor;
  final Color pressedBackgroundColor;
  final VoidCallback onClick;
  final double borderRadius;
  final Color borderColor;

  const CustomTextButton(
      {super.key,
      required this.onClick,
      required this.text,
      this.textSize = 16,
      this.width = double.infinity,
      required this.height,
      this.backgroundColor = Colors.white,
      this.pressedBackgroundColor = Colors.white,
      this.borderRadius = 0.0,
      this.borderColor = Colors.white,
      this.textColor = Colors.black});

  @override
  State<CustomTextButton> createState() => _CustomTextButtonState();
}

class _CustomTextButtonState extends State<CustomTextButton> {
  bool _isPressed = false;

  @override
  Widget build(BuildContext context) {
    return ConstrainedBox(
      constraints:
          BoxConstraints.expand(width: widget.width, height: widget.height),
      child: GestureDetector(
        onTap: () {
          widget.onClick();
        },
        onTapDown: (details) {
          setState(() {
            _isPressed = true;
          });
        },
        onTapUp: (details) {
          setState(() {
            _isPressed = false;
          });
        },
        child: Container(
          alignment: Alignment.center,
          decoration: BoxDecoration(
              color: _isPressed
                  ? widget.pressedBackgroundColor
                  : widget.backgroundColor,
              borderRadius: BorderRadius.circular(widget.borderRadius),
              border: Border.fromBorderSide(
                  BorderSide(width: 1, color: widget.borderColor))),
          child: Text(
            widget.text,
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
            style: TextStyle(
              color: widget.textColor,
              fontSize: widget.textSize,
              fontStyle: FontStyle.normal,
            ),
          ),
        ),
      ),
    );
  }
}

extension HexColor on Color {
  /// String is in the format "aabbcc" or "ffaabbcc" with an optional leading "#".
  static Color fromHex(String hexString) {
    final buffer = StringBuffer();
    if (hexString.length == 6 || hexString.length == 7) buffer.write('ff');
    buffer.write(hexString.replaceFirst('#', ''));
    return Color(int.parse(buffer.toString(), radix: 16));
  }

}

代码演示，如何使用，这个还是非常简单易懂的，有什么需要改进的地方，也请大佬指示改进。

Container(
                  margin: const EdgeInsets.only(left: 20, right: 20),
                  child: CustomTextButton(
                    text: '注册',
                    textSize: 18,
                    textColor: Colors.white,
                    backgroundColor: HexColor.fromHex("F9AC00"),
                    pressedBackgroundColor: HexColor.fromHex("E0CE32"),
                    height: 44,
                    borderRadius: 30,
                    onClick: () {
                      Fluttertoast.showToast(
                          msg: "您按了注册",
                          toastLength: Toast.LENGTH_SHORT,
                          gravity: ToastGravity.BOTTOM,
                          timeInSecForIosWeb: 1,
                          backgroundColor: Colors.black12,
                          textColor: Colors.black,
                          fontSize: 14.0);
                    },
                  ),
                ),