Why Is OnNavigatedTo firing in different ways

[GWawrzeniecki]

Hello

I have different ViewModels which are implementing the INavigationAware interface.
In one ViewModel OnNavigatedTo is firing just after the constructor and all the binding are working properly and in the second view model the OnNavigatedTo is firing after the bindings which results in binding errors.
It's really disappointing.

[brianlagunas]

Without any context to the code you are using, which is usually the first source of any potential issues, Prism does not control when the .NET Framework bindings happen. Also, having OnNavigated to fired after the bindings does not cause a binding error. Binding errors occur when a binding cannot be found on the data context. So either the data context has not been set yet, or the property doesn't exist on the data context.

[GWawrzeniecki]

I could add a null check-in for all properties which are bind to the view.
So this is the only way I can solve this?

[brianlagunas]

I really have no idea what your issue is. If you are getting runtime null exceptions, then yes you have to guard against null.

[GWawrzeniecki]

View Model:
https://github.com/GWawrzeniecki/Pawnshop/blob/master/Modules/PawnShop.Modules.Contract/ViewModels/RenewContractDataViewModel.cs
View:
https://github.com/GWawrzeniecki/Pawnshop/blob/master/Modules/PawnShop.Modules.Contract/Views/RenewContractData.xaml

Here you have the code where I have this issue

[brianlagunas]

You are using object instances (and properties off that object) in your getters of other properties without checking for null.

[GWawrzeniecki]

okay, so I will just add null checks.
Thank you very much for your valuable time.