Button becomes grayed out when command is added to it

[Avngarde]

Hello! There's an issue i couldn't find solution for. When i add a command to a button it becomes grayed out, and it's not click able.

<Button Width="80" Height="50" HorizontalAlignment="Right" VerticalAlignment="Center" IsEnabled="True" Margin="0,0,10,0" Command="{Binding OnButtonClick}">Play now</Button>

private void OnButtonClick(object sender, RoutedEventArgs e) { Console.WriteLine("Played!"); }

[maxkatz6]

I am not sure about Avalonia, but in WPF and UWP Binding doesn't support event handlers as Command value (except x:Bind in UWP, but it is special). So you need use just Click="OnButtonClick" without commands.

Or create property of type ICommand, for example:

public ICommand ButtonClickCommand { get; }

Command="{Binding ButtonClickCommand}"

You should also implement ICommand or find some MVVM framework with it. Something like ReactiveUI.

[Avngarde]

So i should rather implement the command in ViewModel with ReactiveUI than in view?

[maxkatz6]

@ShamanDev for MVVM - yes, commands should be defined in ViewModel.

[Avngarde]

I think i found the real issue here. Command makes my button grayed out when it's part of ItemsPresenter, yet implementing command in ViewModel with ReactiveUI works for buttons outside of it.

[jpgarza93]

Can we reopen this? I have the same issue. I am using MvvmToolkit to create my commands.

ViewModel c#

[RelayCommand]
private async Task StartRecorderAsync()

and then in xaml

<Button Content="Start" Command="{Binding StartRecorderCommand}"/>

This will result in a grayed-out button in the VS22 UI preview

[timunie]

Use CompiledBindings

[jpgarza93]

I do use compile bindings.

my current workaround to enable buttons in UI preview is to add Priority like this:

<Button Content="Start" Command="{Binding StartRecorderCommand, Priority=1}"/>

[timunie]

Please open a new Q&A with a sample attached. I'll not reopen such an old issue, must be something similar but not the exact same thing. Thx.