diff options
Diffstat (limited to 'Xamarin.Forms.Core/NavigationPage.cs')
| -rw-r--r-- | Xamarin.Forms.Core/NavigationPage.cs | 72 |
1 files changed, 22 insertions, 50 deletions
diff --git a/Xamarin.Forms.Core/NavigationPage.cs b/Xamarin.Forms.Core/NavigationPage.cs index 7663d1bf..7b393b9c 100644 --- a/Xamarin.Forms.Core/NavigationPage.cs +++ b/Xamarin.Forms.Core/NavigationPage.cs @@ -1,6 +1,5 @@ using System; using System.Collections.Generic; -using System.Collections.ObjectModel; using System.Linq; using System.Threading.Tasks; using Xamarin.Forms.Internals; @@ -28,10 +27,7 @@ namespace Xamarin.Forms static readonly BindablePropertyKey CurrentPagePropertyKey = BindableProperty.CreateReadOnly("CurrentPage", typeof(Page), typeof(NavigationPage), null); public static readonly BindableProperty CurrentPageProperty = CurrentPagePropertyKey.BindableProperty; - - static readonly BindablePropertyKey RootPagePropertyKey = BindableProperty.CreateReadOnly(nameof(RootPage), typeof(Page), typeof(NavigationPage), null); - public static readonly BindableProperty RootPageProperty = RootPagePropertyKey.BindableProperty; - + public NavigationPage() { _platformConfigurationRegistry = new Lazy<PlatformConfigurationRegistry<NavigationPage>>(() => new PlatformConfigurationRegistry<NavigationPage>(this)); @@ -65,23 +61,17 @@ namespace Xamarin.Forms internal Task CurrentNavigationTask { get; set; } - Page INavigationPageController.Peek(int depth) + Stack<Page> INavigationPageController.StackCopy { - if (depth < 0) - { - return null; - } - - if (PageController.InternalChildren.Count <= depth) + get { - return null; + var result = new Stack<Page>(PageController.InternalChildren.Count); + foreach (Page page in PageController.InternalChildren) + result.Push(page); + return result; } - - return (Page)PageController.InternalChildren[PageController.InternalChildren.Count - depth - 1]; } - IEnumerable<Page> INavigationPageController.Pages => PageController.InternalChildren.Cast<Page>(); - int INavigationPageController.StackDepth { get { return PageController.InternalChildren.Count; } @@ -95,12 +85,6 @@ namespace Xamarin.Forms private set { SetValue(CurrentPagePropertyKey, value); } } - public Page RootPage - { - get { return (Page)GetValue(RootPageProperty); } - private set { SetValue(RootPagePropertyKey, value); } - } - public static string GetBackButtonTitle(BindableObject page) { return (string)page.GetValue(BackButtonTitleProperty); @@ -313,14 +297,8 @@ namespace Xamarin.Forms void InsertPageBefore(Page page, Page before) { - if (page == null) - throw new ArgumentNullException($"{nameof(page)} cannot be null."); - - if (before == null) - throw new ArgumentNullException($"{nameof(before)} cannot be null."); - if (!PageController.InternalChildren.Contains(before)) - throw new ArgumentException($"{nameof(before)} must be a child of the NavigationPage", nameof(before)); + throw new ArgumentException("before must be a child of the NavigationPage", "before"); if (PageController.InternalChildren.Contains(page)) throw new ArgumentException("Cannot insert page which is already in the navigation stack"); @@ -331,9 +309,6 @@ namespace Xamarin.Forms int index = PageController.InternalChildren.IndexOf(before); PageController.InternalChildren.Insert(index, page); - if (index == 0) - RootPage = page; - // Shouldn't be required? if (Width > 0 && Height > 0) ForceLayout(); @@ -344,13 +319,15 @@ namespace Xamarin.Forms if (((INavigationPageController)this).StackDepth == 1) return; - Element[] childrenToRemove = PageController.InternalChildren.Skip(1).ToArray(); - foreach (Element child in childrenToRemove) + var root = (Page)PageController.InternalChildren.First(); + + var childrenToRemove = PageController.InternalChildren.ToArray().Where(c => c != root); + foreach (var child in childrenToRemove) PageController.InternalChildren.Remove(child); - CurrentPage = RootPage; + CurrentPage = root; - var args = new NavigationRequestedEventArgs(RootPage, animated); + var args = new NavigationRequestedEventArgs(root, animated); EventHandler<NavigationRequestedEventArgs> requestPopToRoot = PopToRootRequestedInternal; if (requestPopToRoot != null) @@ -361,7 +338,8 @@ namespace Xamarin.Forms await args.Task; } - PoppedToRoot?.Invoke(this, new PoppedToRootEventArgs(RootPage, childrenToRemove.OfType<Page>().ToList())); + if (PoppedToRoot != null) + PoppedToRoot(this, new PoppedToRootEventArgs(root, childrenToRemove.OfType<Page>().ToList())); } async Task PushAsyncInner(Page page, bool animated) @@ -382,29 +360,24 @@ namespace Xamarin.Forms await args.Task; } - Pushed?.Invoke(this, args); + if (Pushed != null) + Pushed(this, args); } void PushPage(Page page) { PageController.InternalChildren.Add(page); - if (PageController.InternalChildren.Count == 1) - RootPage = page; - CurrentPage = page; } void RemovePage(Page page) { - if (page == null) - throw new ArgumentNullException($"{nameof(page)} cannot be null."); - - if (page == CurrentPage && CurrentPage == RootPage) + if (page == CurrentPage && ((INavigationPageController)this).StackDepth <= 1) throw new InvalidOperationException("Cannot remove root page when it is also the currently displayed page."); if (page == CurrentPage) { - Log.Warning("NavigationPage", "RemovePage called for CurrentPage object. This can result in undesired behavior, consider calling PopAsync instead."); + Log.Warning("NavigationPage", "RemovePage called for CurrentPage object. This can result in undesired behavior, consider called PopAsync instead."); PopAsync(); return; } @@ -413,11 +386,10 @@ namespace Xamarin.Forms throw new ArgumentException("Page to remove must be contained on this Navigation Page"); EventHandler<NavigationRequestedEventArgs> handler = RemovePageRequestedInternal; - handler?.Invoke(this, new NavigationRequestedEventArgs(page, true)); + if (handler != null) + handler(this, new NavigationRequestedEventArgs(page, true)); PageController.InternalChildren.Remove(page); - if (RootPage == page) - RootPage = (Page)PageController.InternalChildren.First(); } void SafePop() |