Does not work correctly on iOS

[alessandrofrancesconi]

I'm using DialogHost.Avalonia 0.7.7 for an app project targeting both Android and iOS. Avalonia framework version is 11.0.6 and .NET version is 7.

Please check the attached sample project. It simply opens a message dialog (MessageDialog.xaml) when clicking the Button.

Running in Debug mode, it works as expected on Android 11. Instead on iOS (different devices from version 15.8 to 16.2) the popup does not open, or it takes a very long time.

Sorry but I cannot test in Release mode as for now, so I cannot tell you if this is related to a particular Configuration.

PopupTest.zip

[SKProCH]

Hello, @alessandrofrancesconi

I'll try to debug this, but I don't own physical iOS device, so only emulator available. If you find any details - please let me know.

[alessandrofrancesconi]

I'm testing on multiple iOS Simulators, and 1 real device. The issue is present in both conditions.

[alessandrofrancesconi]

Just tested in Release mode and the issue remains. It seems that, only on iOS, it is necessary to start tapping at the center of the screen to let the popup appear.

To add more details, I'm using the following version of Microsoft.iOS: 16.2.2054 / 7.0.100. I am not able to upgrade to a more recent version because I'm using Xcode 14.2 and cannot upgrade.

To test it with this very same version, add the following files to the root of the sample project:

global.json

{
  "sdk": {
    "version": "7.0.100",
    "rollForward": "disable",
    "allowPrerelease": false
  }
}

rollback.json

{
  "microsoft.net.sdk.ios": "16.2.2054/7.0.100"
}

Before compiling, run this:

dotnet workload uninstall ios
dotnet workload install ios --from-rollback-file rollback.json

Let me know if you can reproduce it, thanks!

[SKProCH]

Hmm, okay, thanks.

Can you also try to disabling animations from DialogHost. May be it will help?

[alessandrofrancesconi]

Can you also try to disabling animations from DialogHost. May be it will help?

Already tried with no improvements

[SKProCH]

I tried to begin to determine the cause of the error, downloaded your project, and suddenly realized that the rider could not run it.

After a quick search on the Internet, I realized that without having any Apple device (Mac or iPhone), I cannot somehow launch the application. As I understand it, it is impossible to run an iPhone emulator (or some similarity) if you only have Linux/Windows/Android devices.

Perhaps I missed something and this is not true?

[SKProCH]

Also, one of Avalonia maintainers suggesting you to try latest nightly avalonia build. I think than they fix something continuously, and this bug probably on Avalonia side (since it works everywhere except iOS).

[alessandrofrancesconi]

Just tested Avalonia nightly 11.0.999, but the issue remains. I can tell you that, once you click on the "Show popup" button in the project, I have to tap the center of the screen in order to make the popup appear. Seems that the popup is actually there, but invisible. A tap over it will make it appear.

And yes, in order to launch the app on a iOS Device, or an iOS Simulator, you must have an Apple machine paired with your main development PC.

Some links about this limitation:

• https://docs.avaloniaui.net/docs/0.10.x/tutorials/developing-for-mobile/ios/#:~:text=Due%20to%20Apple's%20policies%20it,in%20a%20Window%20sized%20appropriately.
• https://learn.microsoft.com/en-us/dotnet/maui/ios/pair-to-mac?view=net-maui-8.0

Is there something I can do to help you debug this?

[SKProCH]

You're probably not going to gift me an Apple machine to debug this bug 😄...

So, probably not. I'll try to set aside time on the weekends to install and configure macos on a virtual machine, but I think it will take a while.

If you really want to - you can look how the library works, try to recreate a minimal working library and figure out the point at which it stops working. At least I think that's the way I would pick to figure out what's going wrong. But I also think that you don't have the time and/or desire to look into it.

So, keep me informed if you can find out anything.

[SKProCH]

It might also be worth trying to create dialogue content that manually sets changing Height/Width using a timer. Thus, Avalonia will have to redraw its contents - then, perhaps, the dialog will appear automatically after Avalonia redraws it. If so, maybe we'll get closer to understanding what the problem might be.

Also, seems like 11.0.7 version of Avalonia just released. Can you try it too?

[alessandrofrancesconi]

After upgrading to Avalonia 11.0.7 (released 32 minutes ago!) it worked! I don't know why the nightly did not solve...

[SKProCH]

Wow, that's wonderful!