WebView2 in WPF VSTO Addin does not load

[kjb15]

Environment: Visual Studio 2017 Community
NuGet: Microsoft.Web.WebView2, 0.9.628-prerelease
Net Framework: 4.6.2
Project type: VSTO Outlook Addin
Reference: https://docs.microsoft.com/en-us/microsoft-edge/webview2/gettingstarted/wpf

WebView2 does not load any URL inside the control while docked in UserControl of VSTO Addin project

XAML page:

XAML.cs page:

Addin.cs page:

Outlook Custom Task Pane view:

Can someone look into this issue?

Thanks

[champnic]

Have you checked out the other VSTO issues? In particular:
#187

Was WebView2 working in your VSTO before docking it in the UserControl?

I also noticed you are using the Source property rather than EnsureCoreWebView2Async. That does implicit initialization and will create a default UserDataFolder where the code lives, which will be in C:\Program Files... and the Runtime won't have write permissions, so will fail. You need to specify a UserDataFolder somewhere else, using EnsureCoreWebView2Async, or CoreWebView2CreationProperties with Source property.

[kjb15]

Thanks @champnic Appreciate the quick response. Certainly, this worked for me:

var env = await CoreWebView2Environment.CreateAsync(null, @"C:\temp");
await webView.EnsureCoreWebView2Async();

Wondering about what should be the workaround while deploying to Production?

[champnic]

This isn't a workaround per se, it's just a necessary part of writing the VSTO with WebView2. That said, you should probably pick a different location for the UserDataFolder (besides C:\temp) before deploying to production, to make it less accessible and unique to your VSTO. Potentially somewhere in the AppData folder?

[champnic]

I'm going to close this issue. If you'd like me to reopen please let me know with extra details, or open a new issue if you run into something else. Thanks!

[abhinovpankaj]

I am facing this similar issue.
Have tried the method mentioned in the thread but it still fails to resolve my issue.

Code in my WPF mainwindow.xaml.cs#

public LoginControl()
        {
            InitializeComponent();

            webView.Initialized += WebView_Initialized;
            webView.BringIntoView();
            
        }

        private void  WebView_Initialized(object sender, EventArgs e)
        {
             InitializeAsync();
        }

     
        public async void InitializeAsync()
        {
            string folder = @"C:\temp"; //Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
            var env = await CoreWebView2Environment.CreateAsync(null, folder);
            await webView.EnsureCoreWebView2Async(env);

            webView.CoreWebView2.Navigate("https://www.microsoft.com");
            webView.CoreWebView2.WebResourceResponseReceived += CoreWebView2_WebResourceResponseReceived;

        }

Additonally if I diectly call InitializeAsync from LoginControl constructor, I get below exception

System.InvalidOperationException: 'EnsureCoreWebView2Async cannot be used before the application's event loop has started running.'

[champnic]

Hey @abhinovpankaj - what is the error you get when trying the "C:\temp" folder?

[abhinovpankaj]

webview just wont display the page.

[champnic]

@abhinovpankaj do you have a sample app you would be able to share that reproduces this issue? Thanks!

[abhinovpankaj]

https://github.com/point5nyble/OutlookPopup

Git repo with the source code. it's an Outlook Add-on project. It's the withLicensing__ branch .
It's in development so few extra projects and a bit of test and trial code here and there
But the webview2 logic has been written in LoginControl.

Thanks
Abhinov

[abhinovpankaj]

@champnic

@abhinovpankaj do you have a sample app you would be able to share that reproduces this issue? Thanks!

Did you get chance to check on this?