{"id":485,"date":"2012-02-01T15:23:01","date_gmt":"2012-02-01T14:23:01","guid":{"rendered":"https:\/\/ridgesolutions.ie\/?p=485"},"modified":"2013-10-15T15:37:20","modified_gmt":"2013-10-15T14:37:20","slug":"example-of-calling-dispatcher-directly-from-non-ui-code-in-net-wpf","status":"publish","type":"post","link":"https:\/\/www.ridgesolutions.ie\/index.php\/2012\/02\/01\/example-of-calling-dispatcher-directly-from-non-ui-code-in-net-wpf\/","title":{"rendered":"Example of Calling Dispatcher Directly from non-UI code in .NET WPF"},"content":{"rendered":"

.NET’s Threading module isn’t the best, it has the look of a model that was designed by the type of software people who like to keep practical multi-threading a good long arm’s length away. It’s workable but sometimes it requires that you jump through hoops to do simple everyday things with threads – like updating a UI element from a non UI thread etc. You may see errors akin to the following:<\/p>\n

<\/div>\n

“Must create DependencySource on same Thread as the DependencyObject.”<\/p><\/blockquote>\n

“This type of CollectionView does not support changes to its SourceCollection from a thread different from the Dispatcher thread.”<\/p><\/blockquote>\n

To get around this all a .NET developer needs to do is to remember a few ritualistic looking invocations to appease the .NET small gods – but of course I can never remember the details so am recording one such here:<\/p>\n

<\/div>\n

To dispatch to the UI from a non-UI thread and non-UI code, use something like the following:<\/p>\n

<\/div>\n
\r\nusing System.Windows;\r\n\r\nApplication.Current.Dispatcher.Invoke(new Action (() => Thumbnails.Add(thumbnail)));\r\n<\/pre>\n
<\/div>\n","protected":false},"excerpt":{"rendered":"
.NET’s Threading module isn’t the best, it has the look of a model that was designed by the type of software people who like to keep practical multi-threading a good long arm’s length away. It’s workable but sometimes it requires that you jump through hoops to do simple everyday things with threads – like updating […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,1],"tags":[57,189,190,187],"class_list":["post-485","post","type-post","status-publish","format-standard","hentry","category-tech-stuff","category-uncategorized","tag-net","tag-threading","tag-ui","tag-wpf"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t