[GTK] Fix visibility of hidden pages in the stack (#3904)

ylatuya · PureWeen · commit b5b9404bda76 · 2018-10-02T12:45:16.000-06:00
When navigating to a new page, we should hide the previous
content and show the new one so that the previous page
renderer is not taken in account for redraws and resizes
diff --git a/Xamarin.Forms.Platform.GTK/Controls/Page.cs b/Xamarin.Forms.Platform.GTK/Controls/Page.cs
@@ -1,6 +1,7 @@
 ﻿using Gdk;
 using Gtk;
 using System;
+using System.Linq;
 using Xamarin.Forms.Platform.GTK.Extensions;
 
 namespace Xamarin.Forms.Platform.GTK.Controls
@@ -93,6 +94,22 @@ public void SetBackgroundImage(string backgroundImagePath)
 			}
 		}
 
+		public void PushModal(Widget modal)
+		{
+			Children.Last().Hide();
+			Attach(modal, 0, 1, 0, 1);
+			modal.ShowAll();
+		}
+
+		public void PopModal(Widget modal)
+		{
+			if (Children.Length > 0)
+			{
+				Remove(modal);
+			}
+			Children.Last().Show();
+		}
+
 		public override void Dispose()
 		{
 			base.Dispose();
diff --git a/Xamarin.Forms.Platform.GTK/Platform.cs b/Xamarin.Forms.Platform.GTK/Platform.cs
@@ -181,28 +181,7 @@ Task<Page> INavigation.PopModalAsync(bool animated)
 
 			Device.BeginInvokeOnMainThread(() =>
 			{
-				if (pageControl != null)
-				{
-					var page = pageControl.Control;
-
-					if (page != null)
-					{
-						if (page.Children.Length > 0)
-						{
-							page.Remove(modalPage);
-						}
-
-						if (page.Children != null)
-						{
-							foreach (var child in page.Children)
-							{
-								child.ShowAll();
-							}
-
-							page.ShowAll();
-						}
-					}
-				}
+				pageControl?.Control?.PopModal(modalPage);
 
 				DisposeModelAndChildrenRenderers(modal);
 			});
@@ -258,17 +237,7 @@ Task INavigation.PushModalAsync(Page modal, bool animated)
 
 					if (page != null)
 					{
-						page.Attach(modalRenderer.Container, 0, 1, 0, 1);
-
-						if (page.Children != null)
-						{
-							foreach (var child in page.Children)
-							{
-								child.ShowAll();
-							}
-
-							page.ShowAll();
-						}
+						page.PushModal(modalRenderer.Container);
 					}
 				}
 			});
diff --git a/Xamarin.Forms.Platform.GTK/Renderers/NavigationPageRenderer.cs b/Xamarin.Forms.Platform.GTK/Renderers/NavigationPageRenderer.cs
@@ -330,7 +330,7 @@ private async Task<bool> AddPageAsync(Page page, bool animated)
 			if (oldPage != null && Platform.GetRenderer(oldPage) != null)
 			{
 				var oldPageRenderer = Platform.GetRenderer(oldPage);
-				oldPageRenderer.Container.Sensitive = false;
+				oldPageRenderer.Container.Visible = false;
 			}
 
 			return true;
@@ -343,7 +343,7 @@ private async Task RemovePageAsync(Page page, bool removeFromStack, bool animate
 			if (oldPage != null && Platform.GetRenderer(oldPage) != null)
 			{
 				var oldPageRenderer = Platform.GetRenderer(oldPage);
-				oldPageRenderer.Container.Sensitive = true;
+				oldPageRenderer.Container.Visible = true;
 			}
 
 			(page as IPageController)?.SendDisappearing();

Original file line number	Diff line number	Diff line change
`@@ -330,7 +330,7 @@ private async Task<bool> AddPageAsync(Page page, bool animated)`
`330`	`330`	`if (oldPage != null && Platform.GetRenderer(oldPage) != null)`
`331`	`331`	`{`
`332`	`332`	`var oldPageRenderer = Platform.GetRenderer(oldPage);`
`333`		`- oldPageRenderer.Container.Sensitive = false;`
	`333`	`+ oldPageRenderer.Container.Visible = false;`
`334`	`334`	`}`
`335`	`335`
`336`	`336`	`return true;`
`@@ -343,7 +343,7 @@ private async Task RemovePageAsync(Page page, bool removeFromStack, bool animate`
`343`	`343`	`if (oldPage != null && Platform.GetRenderer(oldPage) != null)`
`344`	`344`	`{`
`345`	`345`	`var oldPageRenderer = Platform.GetRenderer(oldPage);`
`346`		`- oldPageRenderer.Container.Sensitive = true;`
	`346`	`+ oldPageRenderer.Container.Visible = true;`
`347`	`347`	`}`
`348`	`348`
`349`	`349`	`(page as IPageController)?.SendDisappearing();`