您好 umi,
正常情况下,当我们在XAML视图中选中集合控件的某一项的时候。 Design视图就会显示中此集合控件的所有元素并高亮显示被选中的那一个元素。

当你的控件变得比较复杂的时候,Design视图有可能无法把所有的元素都正确的显示。 我们仍然可以通过属性视图来修改被选中的集合控件某一项的样式。
Best Regards,
Li Wang
We are trying to better understand customer views on social support experience, so your participation in this interview project would be greatly appreciated if you have time. Thanks for helping make community forums a great place.
Click
HERE to participate the survey.