NullReferenceException when XAML Hot Reload (and other cases)

[casas333]

Hi,

I'm experiencing Null Reference exceptions, at least when the XAML Hot Reload is executed in a page where a Plugin.HibridWebView is located.

Steps to reproduce:

1. Have a XAML page with a Plugin.HybridWebView
2. Activarte XAML Hot Reload for Xamarin.Forms
3. Debug the app to a device
4. Make a change in the XAML and save. Hot Reload is executed

expected: Hot Reload is executed without any crash

current: app crashes because of a null reference exception in the HybridWebView dll.

Stack trace:

at Plugin.HybridWebView.Droid.HybridWebViewRenderer+<>c__DisplayClass34_0.<SetCurrentUrl>b__0 () [0x00016] in <2f2d06da51e84164a0ac7ab59cb79a28>:0 at Java.Lang.Thread+RunnableImplementor.Run () [0x00008] in <d706cf8faf5542949900cf6d57864528>:0 at Java.Lang.IRunnableInvoker.n_Run (System.IntPtr jnienv, System.IntPtr native__this) [0x00009] in <d706cf8faf5542949900cf6d57864528>:0 at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.30(intptr,intptr)

Note: this is just one way that I know for sure makes the plugin crash but it's a more generic issue not really related to the Hot Reload itself, I think. I got this null reference exceptions in other scenarios I can't easily reproduce and explain right now.

[stoff99]

+1

[candidodmv]

Hello @casas333 I'm trying to understand why you are using HotReload in a HTML based control in case this control? does it make sense? Maybe you just need a control to apply a refresh on the control to update the rendering content.

Could you explain better your context to justify spend time in investigate this issue?

[casas333]

Hi @candidodmv,

As I said in the note of my first message, I suspect this issue is not really related to the hot reload, but it was just a way to make the plugin crash. I don't know any other way of reproducing it. So

I was in page where I had de HybridWebView and was working on other page components UI. Suddenly, after a HotReload, the app crashed because of the component, that's it.

Thanks for the reply!