async Task PushHierarchicalView(BaseNavigationPage mainPage, Page page, ViewTransitionArgs transArgs, object args = null)
{
if (transArgs == null)
{
transArgs = new ViewTransitionArgs();
}
if (mainPage != null)
{
var numPages = mainPage.Navigation.NavigationStack.Count;
var currentPage = (numPages > 1) ? mainPage.Navigation.NavigationStack[numPages - 1] : mainPage;
System.Diagnostics.Debug.WriteLine("number of pages in navigationstack for currentpage: " + currentPage.Navigation.NavigationStack.Count);
System.Diagnostics.Debug.WriteLine("number of pages in navigationstack for mainpage: " + mainPage.Navigation.NavigationStack.Count);
if (transArgs.IsModal)
{
await currentPage.Navigation.PushModalAsync(page, transArgs.IsAnimated);
}
else
{
await currentPage.Navigation.PushAsync(page, transArgs.IsAnimated);
}
}
else
{
Application.Current.MainPage = new BaseNavigationPage(page);
}
}
/// <summary>
/// Implements the corresponding method in the INavigationService interface.
/// Removes the current page from the stack.
/// </summary>
/// <param name="transArgs"> to specify if the page is modal </param>
public void PopView(ViewTransitionArgs transArgs)
{
var mainPage = Application.Current.MainPage as BaseNavigationPage;
System.Diagnostics.Debug.WriteLine("before pop: #pages in navigationstack: " + mainPage.Navigation.NavigationStack.Count);
System.Diagnostics.Debug.WriteLine("before pop: #pages in modalstack: " + mainPage.Navigation.NavigationStack.Count);
if (transArgs.IsModal)
{
mainPage.Navigation.RemovePage(mainPage.Navigation.ModalStack[mainPage.Navigation.ModalStack.Count - 1]);
}
else
{
mainPage.Navigation.RemovePage(mainPage.Navigation.NavigationStack[mainPage.Navigation.NavigationStack.Count - 1]);
}
}
/// <summary>
/// Implements the corresponding method in the INavigationService interface.
/// </summary>
/// <param name="page"> page to navigate to </param>
/// <param name="transArgs"> isModal and isAnimated </param>
/// <param name="args"> optional paraters for the page </param>
/// <returns></returns>
public async Task PushView(Page page, ViewTransitionArgs transArgs, object args = null)
{
var mainPage = Application.Current.MainPage;
if (mainPage == null)
{
Application.Current.MainPage = new MasterDetailPage();
}
if (mainPage is MasterDetailPage)
{
await PushDetailView(mainPage as MasterDetailPage, page, args);
}
else if (mainPage is BaseNavigationPage)
{
await PushHierarchicalView(mainPage as BaseNavigationPage, page, transArgs, args);
}
}
