Basically I've got a command binding for the command itself assigned to Window.CommandBindings:
<CommandBinding Command="local:TimerViewModel.AddTimer"
CanExecute="local:TimerViewModel.AddTimer_CanExecute"
Executed="local:TimerViewModel.AddTimer_Executed" />
local is a namespace generated by default pointing to the namespace of the application. What I'm trying to achieve here is to have the command handling inside the TimerViewModel but I keep getting the following error:
CanExecute="local:TimerViewModel.AddTimer_CanExecute" is not valid. 'local:TimerViewModel.AddTimer_CanExecute' is not a valid event handler method name. Only instance methods on the generated or code-behind class are valid.
The TimerViewModel is pretty simple though but I believe I am missing something:
public class TimerViewModel : ViewModelBase
{
public TimerViewModel()
{
_timers = new ObservableCollection<TimerModel>();
_addTimer = new RoutedUICommand("Add Timer", "AddTimer", GetType());
}
private ObservableCollection<TimerModel> _timers;
public ObservableCollection<TimerModel> Timers
{
get { return _timers; }
}
private static RoutedUICommand _addTimer;
public static RoutedUICommand AddTimer
{
get { return _addTimer; }
}
public void AddTimer_CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = true;
}
public void AddTimer_Executed(object sender, ExecutedRoutedEventArgs e)
{
_timers.Add(new TimerModel(TimeSpan.FromSeconds((new Random()).Next())));
}
}
Can anyone point out the mistakes I'm making?
Also take a look at Josh Smith's RelayCommand. Using it would enable you to write the above like this:
public class TimerViewModel : ViewModelBase {
public TimerViewModel() {
Timers = new ObservableCollection<TimerModel>();
AddTimerCommand = new RelayCommand(() => AddTimer());
}
public ObservableCollection<TimerModel> Timers {
get;
private set;
}
public ICommand AddTimerCommand {
get;
private set;
}
private void AddTimer() {
Timers.Add(new TimerModel(TimeSpan.FromSeconds((new Random()).Next())));
}
}