V3 版本如何自定义header ？

[EsZhangHome]

您好，我想自定义header ，这个header 是一个gif 图，用老版本的时候可以这样自定义，现在V3 版本的我想自定义，改如何自定义。下面是使用老版本库，自定义header 的代码，其中引用了一个 gif 图。 `///自定义顶部加载提示动画 class CustomRefreshHeader extends Header { /// Key final Key key;

final LinkHeaderNotifier linkNotifier = LinkHeaderNotifier();

CustomRefreshHeader({ this.key, bool enableHapticFeedback = true, bool enableInfiniteRefresh = false, }) : super( extent: 100.0, triggerDistance: 100.0, float: false, enableHapticFeedback: enableHapticFeedback, enableInfiniteRefresh: enableInfiniteRefresh, );

@override Widget contentBuilder( BuildContext context, RefreshMode refreshState, double pulledExtent, double refreshTriggerPullDistance, double refreshIndicatorExtent, AxisDirection axisDirection, bool float, Duration completeDuration, bool enableInfiniteRefresh, bool success, bool noMore) { // 不能为水平方向 assert( axisDirection == AxisDirection.down || axisDirection == AxisDirection.up, 'Widget cannot be horizontal'); linkNotifier.contentBuilder( context, refreshState, pulledExtent, refreshTriggerPullDistance, refreshIndicatorExtent, axisDirection, float, completeDuration, enableInfiniteRefresh, success, noMore); return Stack( children: [ Positioned( top: 0.0, bottom: 0.0, left: 0.0, right: 0.0, child: Container( alignment: Alignment.bottomCenter, color: Colors.transparent, child: Row( mainAxisAlignment: MainAxisAlignment.center, children: [ Image.asset( Assets.imgLoadingTop, width: 100, height: 100, ), ], ), ), ), ], ); } }`

[xuelongqy]

参考已有样式哈，照着写就可以，主要是高度和指示器的几个状态