在Flutter 时，容器有填充物:
padding: const EdgeInsets.only(
left: MyMeasurements.globalLeftPadding,
right: 20.0,
),
我希望能够推翻"左"字.
如果我这样做，我会得到一个运行时错误:
class MySectionHeader extends StatelessWidget {
final double left;
MySectionHeader({
this.left,
});
// down to the widget body
padding: const EdgeInsets.only(
left: left ?? MyMeasurements.globalLeftPadding,
right: 20.0,
),
// and in the container that has the override...
new MySectionHeader(
left: 12.0,
),
这还会得到一个运行时错误:
padding: const EdgeInsets.only(
left: left ?? 14.0,
right: 20.0,
),
// and in the container that has the override...
new MySectionHeader(
left: 12.0,
),
有什么建议吗？