FractionallySizedBox

一个将其子部件大小调整为总可用空间一定比例的部件。有关布局算法的更多细节,请参见 RenderFractionallySizedOverflowBox

示例

SizedBox.expand(
  child: FractionallySizedBox(
    widthFactor: 0.5,
    heightFactor: 0.5,
    alignment: Alignment.center,
    child: DecoratedBox(
      decoration: BoxDecoration(border: Border.all(color: Colors.blue, width: 4)),
    ),
  ),
)

这个例子展示了根据Factor系数将子组件的宽高都设置为父组件的50%,根据alignment设置排列子组件在父组件中间。

构造函数

FractionallySizedBox.new({
  Key? key, 
  AlignmentGeometry alignment = Alignment.center, 
  double? widthFactor, 
  double? heightFactor, 
  Widget? child
})

属性

属性名属性类型说明
alignmentAlignmentGeometry对齐方式
childWidget?子组件
heightFactordouble?高度系数
widthFactordouble?宽度系数