小编use*_*644的帖子

我用MVVM模式创建了最简单的WPF项目.如何ShowMessageAsync从我的viewModel 调用？

 if (DisciplineText!="")
 {
     Disciplines.Add(new Discipline(){ChairID = SelectedChair.ChairID,SemesterID = SelectedSemester.SemesterID,Discipline1 = DisciplineText});
     Context.SaveChanges();
 }
 else
 {
     //  ShowMessageAsync????????
 }