Flutter学习--Wrap组件

一、介绍

Wrap流式布局组件，一行或者一列放不下子组件时，会自动换行

二、Wrap源码

Wrap({
    Key key,
    this.direction = Axis.horizontal,//排列方向
    this.alignment = WrapAlignment.start,//x轴对齐方式
    this.spacing = 0.0,//x轴子组件间距
    this.runAlignment = WrapAlignment.start,//y轴对齐方式
    this.runSpacing = 0.0,//y轴子元素间距
    this.crossAxisAlignment = WrapCrossAlignment.start,
    this.textDirection,//x轴文本方向
    this.verticalDirection = VerticalDirection.down,//y轴文本方向
    this.clipBehavior = Clip.hardEdge,
    List children = const [],//子组件集合
  }) : assert(clipBehavior != null), super(key: key, children: children);

三、Wrap属性介绍

属性	说明
direction	Axis.horizontal水平排列 Axis.vertical垂直排列
alignment	x轴对齐方式 WrapAlignment.start 默认左对齐 WrapAlignment.end 默认右对齐 WrapAlignment.center居中对齐 WrapAlignment.spaceBetween左右对齐 间距与控件 同时平分空间 WrapAlignment.spaceAround左右对齐 间距平分 两边没间隙 WrapAlignment.spaceEvenly/左右对齐 间距平分 两边有间隙
spacing	x轴间距
runAlignment	y轴对齐方式 WrapAlignment.start 默认顶部对齐 WrapAlignment.end 默认底部对齐 WrapAlignment.center居中对齐 WrapAlignment.spaceBetween左右对齐 间距与控件 同时平分空间 WrapAlignment.spaceAround左右对齐 间距平分 两边没间隙 WrapAlignment.spaceEvenly/左右对齐 间距平分 两边有间隙
runSpacing	y轴间距
textDirection	x轴文本方向 TextDirection.ltr从左往右 TextDirection.rtl从右往左
verticalDirection	y轴文本方向 VerticalDirection.down从上往下 VerticalDirection.up从下往上
children	子组件集合

四、demo

class WrapStu extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      color: Colors.amberAccent,
      width: 500,
      height: 500,
      child: Wrap(
        direction: Axis.horizontal,
        textDirection: TextDirection.ltr,
        verticalDirection: VerticalDirection.down,
        alignment: WrapAlignment.spaceAround,
        spacing: 10,
        runSpacing: 10,
        runAlignment: WrapAlignment.center,
        crossAxisAlignment: WrapCrossAlignment.center,
        children: [
          MyText("111111"),
          MyText("222"),
          MyText("333333333"),
          MyText("4433333"),
          MyText("55555555555555"),
          MyText("6666")
        ],
      ),
    );
  }
}

class MyText extends StatelessWidget {
  String msg;

  MyText(this.msg);

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: EdgeInsets.fromLTRB(8, 10, 8, 10),
      decoration: BoxDecoration(
          border: Border.all(color: Colors.red, width: 1),
          borderRadius: BorderRadius.all(Radius.circular(8))),
      child: Text(msg),
    );
  }
}

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