relaycommand

What is the Difference between the RoutedCommand and RelayCommand ? When to use RoutedCommand and when to use RelayCommand in MVVM pattern ? wekempf RoutedCommand is part of WPF, while RelayCommand was created by a WPF Disciple, Josh Smith ;). Seriously, though, RS Conley described some of the differences. The key difference is that RoutedCommand is an ICommand implementation that uses a RoutedEvent to route through the tree until a CommandBinding for the command is found, while RelayCommand does no routing and instead directly executes some delegate. In a M-V-VM scenario a RelayCommand

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 =

Consider the reference Josh Smith' article WPF Apps With The Model-View-ViewModel Design Pattern , specifically the example implementation of a RelayCommand (In Figure 3). (No need to read through the entire article for this question.) In general, I think the implementation is excellent, but I have a question about the delegation of CanExecuteChanged subscriptions to the CommandManager 's RequerySuggested event. The documentation for RequerySuggested states: Since this event is static, it will only hold onto the handler as a weak reference. Objects that listen for this event should keep a

How can I use the RelayCommand in wpf? Relay command doesn't exist in WPF, it is just a external class that raised to prominence after it was defined in this MSDN article . You need to write it yourself if you want to use it. Otherwise you can you the Delegate command from the WPF toolkit here which has a little bit of extra functionality over the RelayCommand code. Ah, the question changed while I was typing this answer. Assuming that you are using the RelayCommand as defined above you need to supply it with one or two delegates, one that returns a bool which determines whether the command is