MessageBox.Show from ViewModel?

[acormier]

Hi,
Trying to get my head around using RxUI. In
ReactiveUI.Samples / ReactiveUI.Samples.Commands / RxUI / MainVIewModel.cs
There's a call to MessageBox.Show(...). That seems wrong. Shouldn't that be in the view?

[arielbh]

Basically you are right, but the samples are intended to show Rx in the most simple way possible.
You can hide the MessageBox beyond a service.

[anaisbetts]

Definitely. One good MVVM-correct way to show message boxes is through the UserError framework, here's the docs on how that works

[acormier]

Thanks. That's great info on errors.

What I was doing when I looked up this example was a command to open a file. It goes like this:

• A btn is bound to a GetFilePath ReactiveCommand that's in the VM
• from the view constructor: this.ViewModel.GetFilePath.Subscribe(_ => OpenFileDialog and pass file name to BLL.OpenFile)
• BLL.OpenFile(fileName) (legacy code that I can't change) reads file and fires OnOpenFile event
• handle OnOpenFile event in VM and add the content to a property that's bound to a Text control

I need to find the RxUI way of doing the last step but otherwise I hope I'm on the right track.

This is probably not the right place to post this ...
Thanks

[anaisbetts]

Observable.FromEventPattern<STUFF,OTHERSTUFF>(x => OnOpenFile += x)
    .InvokeCommand(this, x => x.ViewModel.FileChosen);

FileChosen.Subscribe(x => {
    var file = (string)x;
    // Do a Thing
});