类似的还有其他三个属性ChatEnabled、UserInfoEnabled、GroupMebEnabled，我通过控制MainState来控制界面UserControl的显隐： 之前我也是这样做的，不过控制的是普通界面元素的显隐（如Button，Textbook等），但是我发现同样的方法用在UserControl上就不管用了（结果是全部显示）。

Model-view-viewmodel works well with XAML and .NET. Now there’s a first-class implementation from the .NET community Microsoft has always been good at working with developers, right from its earliest ...

After the first part of this series dealt with Windows Forms, we will now look at Windows Presentation Foundation (WPF) and Windows UI Library 3 (WinUI 3). Both GUI frameworks are based on XAML ...