Unity 5.4.1f1 - No keyboard input for native UWP element (WebView)

Try adding -dontConnectAcceleratorEvent command line argument.
Regardless of result please report a bug.

 

This will be pointless without your repro project, so please submit a bug.

 

We connect to AcceleratorEvent on CoreWindow in order to receive certain keyboard keys that are not available in other events. This flag disables that, which means we don't connect the even and won't handle those keys (F10, Shift, Alt, Ctrl keys should be tested in your app now, some will not be seen by Unity).

It looks we broke the event handler when fixing issues with touch screen keyboard ('@' was impossible to type in some languages).

Missing documentation is another bug

 

Hey Maisey,

I've looked at this problem...Sadly the code

Code (csharp):

1.  
2. var simpleWebView = new WebView();
3. simpleWebView.Source = new Uri("https://google.com");
4. var someDialog = new ContentDialog();
5. someDialog.Content = simpleWebView;
6.  
7. someDialog.ShowAsync();
8.  

doesn't work for me, as in the webpage is never loaded, so I can't reproduce the problem with this script. So I tried adding WebView component directly into MainPage.xaml, where webpage would load correctly, but keyboard input worked correctly there, can you confirm that?

I am guessing the issue is, Unity doesn't detect that your control has focus, that's why it's intercepting input.

 

It simply means Unity didn't care about those input events and didn't handle them, that's why WebView was able to handle them instead. But Unity does handle all key events except when it's aware that XAML element (which is a child of SwapChainPanel) is focused, in that case Unity will let that XAML element to handle those.

Now the issue with ContentDialog, it's not a part of MainPage XAML tree view, by the looks of it, it's a child of a Popup element, thus Unity is not aware that it's focused and wants key input events.

Still looking what would be the proper way of handling this.

Stay tuned.

 

What if you call UnityPlayer.AppCallbacks.Instance.UnitySetInput(false); before showing that popup window, and then restoring UnityPlayer.AppCallbacks.Instance.UnitySetInput(true) after that window is closed, does that work for you then?

 

Hmph, it should have worked... because it effectively makes Unity unsubscribe from AcceleratorKeyActivated event, which causing the issue.

I think in older versions, there was an opposite effect, while it may worked in this case, the input would also leak to Unity's text field.

Do you have a repro project with winfbsdk involved, because like I said above code doesn't work for me.

 

Hey,

we discussed this problem with Microsoft, on how we can detect that there's a popup window focused, but the workaround was not straightforward, so we're still thinking.

On the other side, I checked UnitySetInput function and it fixes your problem, I guess you've used UnitySetInput function in MainPage constructor, in that case that's wrong, because Unity was still initializing in the background and at some point overwrites that setting, but if you call this function after Unity is intialized everything should work.

 

Like I said, the problem here is Unity has no straight way of detecting that there's a popup window showing, but even if this fixed, if you use UnitySetInput (for enabling/disabling Unity input handling) function, there's no harm in that.

Stay tuned

 

Oh sorry... but sadly no, that specific function comes from UnityPlayer.winmd file which is not referenced by Assembly-CSharp.dll so you can not directly access it.

I guess we could expose such function in https://docs.unity3d.com/ScriptReference/WSA.Application.html, but I doubt it will happen in 5.4.x version.

 

Actually, there may be a way to do this via reflection, will be back in few minutes

 

Alright, it's not very pretty, but it works, and can be executed from inside Unity script.

Code (csharp):

1.  
2. using UnityEngine;
3. using System.Collections;
4. using System;
5.  
6. #if NETFX_CORE
7. using Windows.UI.Xaml.Controls;
8. using System.Reflection;
9. using System.Linq;
10. using Windows.UI.Xaml.Input;
11. #endif
12.  
13. public class NewBehaviourScript : MonoBehaviour
14. {
15.     async void ShowImpl()
16.     {
17. #if NETFX_CORE
18.         UnitySetInput(false);
19.         var simpleWebView = new WebView();
20.         simpleWebView.Source = new Uri("https://google.com");
21.         var someDialog = new ContentDialog();
22.         someDialog.Content = simpleWebView;
23.         someDialog.PrimaryButtonText = "Quit";
24.  
25.         ContentDialogResult res = await someDialog.ShowAsync();
26.  
27.         UnitySetInput(true);
28. #endif
29.     }
30.  
31.     void OnGUI()
32.     {
33.         if (GUILayout.Button("Test"))
34.         {
35.             UnityEngine.WSA.Application.InvokeOnUIThread(() =>
36.             {
37.                 ShowImpl();
38.             }, false);
39.         }
40.     }
41.  
42.     #region Magic
43. #if NETFX_CORE
44.     private object m_AppCallbacksObject;
45.     private MethodInfo m_UnitySetInputMethod;
46.  
47.     private void UnitySetInput(bool enabled)
48.     {
49.         if (m_AppCallbacksObject == null)
50.         {
51.             var app = Windows.UI.Xaml.Application.Current;
52.             var appCallbacksField = app.GetType().GetTypeInfo().DeclaredFields.Where(f => f.Name == "appCallbacks").FirstOrDefault();
53.             m_AppCallbacksObject = appCallbacksField.GetValue(app);
54.             m_UnitySetInputMethod = m_AppCallbacksObject.GetType().GetTypeInfo().DeclaredMethods.Where(m => m.Name == "UnitySetInput").FirstOrDefault();
55.  
56.             if (m_UnitySetInputMethod == null)
57.                 throw new MissingMethodException("Failed to locate UnitySetInput function");
58.         }
59.  
60.         m_UnitySetInputMethod.Invoke(m_AppCallbacksObject, new object[] { enabled });
61.     }
62. #endif
63. #endregion
64. }
65.  
66.  

 

What is the particular issue you're running into? We have no known bug reports open on any related issues as far as I can tell.

 

What if add command line argument: -dontConnectAcceleratorEvent

With this argument some keyboard keys will not be registered by Unity, but if you don't use them, you'll be fine. From memory F7 and some Ctrl or Alt, but better test it, I don't remember exactly.

 

One thing to check is whether you're invoking that API from the correct thread. AppCallbacks methods usually have to be invoked from the UI thread, not from Unity main thread.

As for command line arguments - read this; https://docs.unity3d.com/Manual/CommandLineArguments.html