public MainVM(IShell shell)
{
this.shell = shell;
exitCommand = new DelegateCommand(obj => shell.ExitApplication());
okCommand = new DelegateCommand(OkClicked);
aboutCommand = new DelegateCommand(AboutClicked);
themeCommand = new DelegateCommand(ChangeThemeClicked);
switcherVM = new ThemeSwitcherVM(shell);
countries = InitCountries();
}
