C#•4y ago

❔ Issue with NotifyCanExecuteChangedFor from MVVM CommunityTK

The problem occurs in my view model (Avalonia MVVM), I set a variable

[ObservableProperty]
[NotifyCanExecuteChangedFor(nameof(PreCheckCommand))]
public string username;

[ObservableProperty]
[NotifyCanExecuteChangedFor(nameof(PreCheckCommand))]
public string username;

[ObservableProperty]
[NotifyCanExecuteChangedFor(nameof(PreCheckCommand))]
public string username;

[ObservableProperty]
[NotifyCanExecuteChangedFor(nameof(PreCheckCommand))]
public string username;

and try to run my function

[RelayCommand]
public void PreCheck() { ... }

[RelayCommand]
public void PreCheck() { ... }

[RelayCommand]
public void PreCheck() { ... }

[RelayCommand]
public void PreCheck() { ... }

whenever the text in to box is changed, it never executes though. Anyone has an idea what the issue is?

This is how I use the binding in my xaml

<TextBox ... Text="{Binding Username, Mode=TwoWay}"></TextBox>

<TextBox ... Text="{Binding Username, Mode=TwoWay}"></TextBox>

<TextBox ... Text="{Binding Username, Mode=TwoWay}"></TextBox>

<TextBox ... Text="{Binding Username, Mode=TwoWay}"></TextBox>

Starlk•11/9/22, 5:39 PM

Did you set the data-context for the view?

1FriendlyDogeOP•11/9/22, 5:39 PM

Other bindings work, so yeah

Starlk•11/9/22, 5:39 PM

what UI framework is this?

1FriendlyDogeOP•11/9/22, 5:39 PM

Avalonia MVVM

Twiner•11/9/22, 5:40 PM

Notification is for properties not fields

Twiner•11/9/22, 5:40 PM

In wpf atleast

TTwiner Notification is for properties not fields

1FriendlyDogeOP•11/9/22, 5:41 PM

Everything besides my function executing works, values update etc, so notification isnt the issue

MMelo Blerd You need OnUsernameChanged method that mvvmtoolkit will gen for you. Then from...

1FriendlyDogeOP•11/9/22, 5:44 PM

And how do I get that?

1FriendlyDogeOP•11/9/22, 5:45 PM

not there for me, do I have to put it into the constructor or something? Just typing it in the class doesnt work for me, although the object exists

MMelo Blerd should be private

1FriendlyDogeOP•11/9/22, 5:47 PM

I set the var to private, didnt change anything

1FriendlyDogeOP•11/9/22, 5:47 PM

partial

1FriendlyDogeOP•11/9/22, 5:48 PM

It inherits from ObservableObject

1FriendlyDogeOP•11/9/22, 5:49 PM

Oh, it needed partial void

1FriendlyDogeOP•11/9/22, 5:51 PM

That finally fixed it, wow, 2 hours wasted :( thank you a lot for helping me out!

1FriendlyDogeOP•11/9/22, 5:52 PM

Yeah, I would have never guessed this, pretty weird way to go about this in my opinion...

333fred•11/9/22, 6:00 PM

/cc @Sergio

Sergio•11/9/22, 6:01 PM

You're confusing things

Sergio•11/9/22, 6:01 PM

NotifyCanExecuteChangedForNotifyCanExecuteChangedFor doesn't invoke your command

Sergio•11/9/22, 6:01 PM

It just causes the command to signal its CanExecuteChangedCanExecuteChanged event

11FriendlyDoge The problem occurs in my view model (Avalonia MVVM), I set a variable ```cs [Obs...

Sergio•11/9/22, 6:01 PM

This was in reply to this

Sergio•11/9/22, 6:02 PM

If you want to run code whenever that changes, just do:

partial void OnUsernameChanged(string value)
{
    // TODO: do stuff here
}

partial void OnUsernameChanged(string value)
{
    // TODO: do stuff here
}

Accord•11/22/22, 8:29 PM

Was this issue resolved? If so, run

/close

/close

otherwise I will mark this as stale and this post will be archived until there is new activity.