public MainPage(){
InitializeComponent();
if (phoneAppService.State.TryGetValue("currentLanguage", out someObject))
{ // Yes: go on
var uri = "/Pages/Page_A.xaml";
this.Dispatcher.BeginInvoke(() => this.NavigationService.Navigate(new Uri(uri, UriKind.Relative)));
}
else
{ // No: select language before proceeding
var uri = "/Pages/Page_B.xaml";
this.Dispatcher.BeginInvoke( () => this.NavigationService.Navigate(new Uri(uri, UriKind.Relative)));
}
}
**// if previous page was Page_A or Page_B then exit application**
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
string sourcePage = "";
if (NavigationContext.QueryString.TryGetValue("from", out sourcePage)) {
if ((string.Compare(sourcePage.ToString(), "Page_A")) == 0 ? true : false) {
**// EXIT APPLICATION**
}
if ((string.Compare(sourcePage.ToString(), "Page_B")) == 0 ? true : false) {
**// EXIT APPLICATION**
}
}
base.OnNavigatedTo(e);
}
// Back Button pressed: notify MainPage so it can exit application
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
NavigationService.Navigate(new Uri(uri, UriKind.Relative));
base.OnBackKeyPress(e);
}
// Back Button pressed: notify MainPage so it can exit application
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
var uri = "/MainPage.xaml?from=Page_B";
NavigationService.Navigate(new Uri(uri, UriKind.Relative));
base.OnBackKeyPress(e);
}
RootFrame.Navigated += RootFrame_Navigated;
void RootFrame_Navigated(object sender, NavigationEventArgs e)
{
var pageBURI = "/Pages/Page_B.xaml";
var pageAURI = "/Pages/Page_A.xaml";
if ((e.Uri == pageAURI || e.Uri == pageBURI) && RootFrame.BackStack.Count() > 0)
{
RootFrame.RemoveBackEntry();
}
}