AsyncCommand CanExecute handler

I am using the @Stephen-Cleary AsyncCommand implementation in WPF (.NET 4.0) and now I am trying to find out how to specify the CanExecute handler during command definition.

Usually I create the command like this:

            SaveCommandAsync = AsyncCommand.Create(async token =>
            {
                //async code    
            });

I don't see any Create overload so I can specify CanExecute logic.

Thank you,

Igor

Use Stephen Cleary's Nito.Mvvm.Async project to achieve what you need.

Add nuget reference to the package: <package id="Nito.Mvvm.Async" version="1.0.0-eta-05" targetFramework="net45" />

Create Xaml binding:

<Button Content="Toggle" Command="{Binding MyAsyncCommand}"></Button>

Create CustomAsyncCommand, specifying CanExecute function

MyAsyncCommand = new CustomAsyncCommand(AsyncAction, x=> !_isWorking);

Do some async work in AsyncAction

private async Task AsyncAction(object obj) {
    _isWorking = true;
    MyAsyncCommand.OnCanExecuteChanged();
    await Task.Delay(2000);
    _isWorking = false;
    MyAsyncCommand.OnCanExecuteChanged();
}

And finally: enjoy.