namespace Message_MainApplication.ViewModels; public class MainViewModel : BindableBase { private readonly IRegionManager _regionManager; public MainViewModel(IRegionManager regionManager) { _regionManager = regionManager; OpenCommand = new DelegateCommand(Open); } public DelegateCommand OpenCommand { get; private set; } public void Open(string viewName) { _regionManager.Regions["MainRegion"].RequestNavigate(viewName); } }