After the [feature request] cascade selector initializes the binding of a value ['headquarters'], click to open the drop-down box, and how to expand the next level of the value of the binding at the same time? (or how to trigger an event of a mouse hover option in the source code?)

[wildcatDownstairs]

Existing Component

Yes

Component Name

el-cascader 级联选择器

Description

重现地址：https://codepen.io/nachen/pen/MWaqVYv 需求描述： 如在线代码示例，整个级联选择器一级节点就一个值（真实项目里比如一级节点就是当前用户的公司），所以自然初始化时就默认绑定了这个节点，那么，当我手动打开级联选择器的时候，就应该去自动加载我所绑定的这个值的下一页数据（如果有children）。而不是像现在这样鼠标还得先划到’总公司‘，再展开下级页面

[element-bot]

Translation of this issue:

Existing Component

Yes

Component Name

El cascade cascade selector

Description

Return address: https://codepen.io/nachen/pen/mwaqvyv

Requirement Description: For example, in the online code example, the first level node of the whole cascade selector is a value (for example, the first level node in the real project is the current user's company), so this node is bound by default during natural initialization. When I manually open the cascade selector, I should automatically load the next page of data (if there is children) of this value that I bind. Instead of using the mouse as it is now, you have to click the head office first, and then expand the lower level page

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.