From db68a9741e2d66030bfd97d836aeae94a8cfd1f9 Mon Sep 17 00:00:00 2001
From: Markus Ewald <cygon@nuclex.org>
Date: Sat, 16 Feb 2019 20:06:34 +0000
Subject: [PATCH] The multi page view can now deal with multi page view models
 that change the active page from a different thread (as it should be, in WPF
 all bound property change notifications are allowed to come from any thread)

git-svn-id: file:///srv/devel/repo-conversion/nuwi@56 d2e56fa2-650e-0410-a79f-9358c0239efd
---
 Source/ViewModels/ThreadedViewModel.Test.cs |  4 +++-
 Source/Views/MultiPageViewForm.cs           | 15 +++++++++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/Source/ViewModels/ThreadedViewModel.Test.cs b/Source/ViewModels/ThreadedViewModel.Test.cs
index 0431150..34b9a03 100644
--- a/Source/ViewModels/ThreadedViewModel.Test.cs
+++ b/Source/ViewModels/ThreadedViewModel.Test.cs
@@ -152,7 +152,9 @@ namespace Nuclex.Windows.Forms.ViewModels {
       /// <summary>Runs a background process that causes the specified error</summary>
       /// <param name="error">Error that will be caused in the background process</param>
       public void CauseErrorInBackgroundThread(Exception error) {
-        RunInBackground(() => throw error);
+        RunInBackground(
+          delegate() { throw error; }
+        );
       }
 
       /// <summary>
diff --git a/Source/Views/MultiPageViewForm.cs b/Source/Views/MultiPageViewForm.cs
index 30e0064..a0ebf1f 100644
--- a/Source/Views/MultiPageViewForm.cs
+++ b/Source/Views/MultiPageViewForm.cs
@@ -130,7 +130,7 @@ namespace Nuclex.Windows.Forms.Views {
         Control control = Controls[index];
 
         // Only check container controls
-        if((control is ContainerControl) || (control is Panel)) { 
+        if((control is ContainerControl) || (control is Panel)) {
           if(firstContainer == null) {
             firstContainer = control;
           }
@@ -194,7 +194,14 @@ namespace Nuclex.Windows.Forms.Views {
       if(arguments.AreAffecting(nameof(MultiPageViewModel<object>.ActivePage))) {
         var viewModelAsMultiPageviewModel = DataContext as IMultiPageViewModel;
         if(viewModelAsMultiPageviewModel != null) {
-          activatePageView(viewModelAsMultiPageviewModel.GetActivePageViewModel());
+          if(InvokeRequired) {
+            Invoke(
+              new Action<object>(activatePageView),
+              viewModelAsMultiPageviewModel.GetActivePageViewModel()
+            );
+          } else {
+            activatePageView(viewModelAsMultiPageviewModel.GetActivePageViewModel());
+          }
         }
       }
     }
@@ -210,7 +217,7 @@ namespace Nuclex.Windows.Forms.Views {
         var activePageViewAsView = this.activePageView as IView;
         if(activePageViewAsView == null) {
           return null;
-        } else { 
+        } else {
           return activePageViewAsView.DataContext;
         }
       }
@@ -257,7 +264,7 @@ namespace Nuclex.Windows.Forms.Views {
           disableActivePageView();
         } else {
           Control pageViewContainer = getPageViewContainer();
-          using(new RedrawLockScope(pageViewContainer)) { 
+          using(new RedrawLockScope(pageViewContainer)) {
             disableActivePageView();
 
             this.activePageView = getOrCreatePageView(pageViewModel);