MVVM Light RelayCommand Parameters

Question

I'm having an issue with passing a parameter to a relaycommand using the GalaSoft MVVM Light framework. I know that mvvm light's implementation of relaycommand doesn't use lambda parameters, so I did some research and found a way that people worked around it by doing something like this:

public RelayCommand ProjMenuItem_Edit {     get     {         if (_projmenuItem_Edit == null)         {             //This should work....             _projmenuItem_Edit = new RelayCommand(ProjEditNode);         }         return _projmenuItem_Edit;     } }  private void ProjEditNode(object newText) {     var str = newText as string;     OrganLocationViewModel sel =          ProjectOrganLocationView.GetExtendedTreeView().GetTopNode();      //Console.WriteLine(sel.OrganDisplayName);     sel.OrganDisplayName = str; } 

However, I keep getting an error on the line _projmenuItem_Edit = new RelayCommand(ProjEditNode); that says Argument 1: cannot convert from 'method group' to 'System.Action'

What am I missing?

Answer 1

I believe this will work:

_projmenuItem_Edit = new RelayCommand<object>((txt)=>ProjEditNode(txt)); 

-- EDIT --

You'll need to define your RelayCommand with the type as well:

e.g.

public RelayCommand<string> myCommand { get; private set; } myCommand = new RelayCommand<string>((s) => Test(s));  private void Test(string s) {     throw new NotImplementedException(); }