flutter treeview库的onTap函数如何使用

Question

您好，我正在使用这个 pubdev 包 https://pub.dev/packages/tree_view/example . My problem is that when I use the onTap function the expanded does not work, I was checking the library and I noticed that it is because of this code, however I do not know how to solve it or if there is another way to access that function from the library from the widget. Any ideas

如果你注意到当onTap函数与empty不同时，toggleExpanded()函数不适用

有什么想法吗？？

Answer 1

您需要使用 startExpanded property of the TreeView 小部件自行控制扩展。

首先，您的 StatefulWidget 中有一个布尔变量（比如 _startExpanded），用于保存扩展状态，您可以将其设置为默认状态（例如，false).

bool _startExpanded = false;

然后，您将变量传递给 TreeView 小部件：

TreeView(
    startExpanded: _startExpanded,
    children: _getChildList(documentList),
),

展开，调用：

setState((){
  _startExpanded = true;
});

要关闭，请调用：

setState((){
  _startExpanded = false;
});