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Button not enabling when its CanX property returns true

See original GitHub issue

Reproduced in this repo here:

I’m using the default Stylet template with dotnet core 3.1. I simply added a property/method for reproducing the issue.

<TextBox Text="{Binding Username, 
         Width="100" Height="100"/>

<Button Command="{s:Action Do}">Foo</Button>
public class ShellViewModel : Screen
    public string Username { get; set; }

    public void Do() { }

    public bool CanDo => !string.IsNullOrWhiteSpace(Username);

Breakpoint on CanDo property is hit once and never hit again. Changing the value in the TextBox, while calling set, does not retrigger the CanDo property.

I’ve also tried using backing fields with SetAndNotify, to no avail:

public string Username { get => username; set => SetAndNotify(ref username, value, nameof(Username)); }

Issue Analytics

  • State:closed
  • Created 3 years ago
  • Comments:10 (5 by maintainers)

github_iconTop GitHub Comments

canton7commented, Jul 28, 2020

Yes, you’ll need to raise an INPC event for CanLogin whenever Username changes. I’ll make sure the wiki makes this clear.

I normally wire things together in the constructor:

Bind(s => s.Username, (o, e) => NotifyOfPropertyChange(nameof(CanLogin)));
haven1433commented, Aug 24, 2020

I’d be happy to handle the wiki change if you’d like

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