How to bind WPF button to a command in ViewModelBase?
I have a view AttributeView that contains all sorts of attributes. There's also a button that when pressed, it should set the default values to the attributes. I also have a ViewModelBase class that is a base class for all ViewModels I have. The problem is I can't seem to get the button bound to the command with WPF.
I've tried this, but it just doesn't do anything:
<Button Command="{Binding DataInitialization}" Content="{x:Static localProperties:Resources.BtnReinitializeData}"></Button>
The command is defined (in the ViewModelBase ) like this:
public CommandBase DataInitialization { get; protected set; }
and on application startup a new instance is created for the command:
DataInitialization = new DataInitializationCommand()
However, the WPF binding doesn't seem to "find" the command (pressing the button does nothing). The ViewModel used in the current view is derived from the ViewModelBase . What else I can try (I'm quite new to WPF so this might be a very simple question)?
<Grid >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button Command="{Binding ClickCommand}" Width="100" Height="100" Content="wefwfwef"/>
</Grid>
the code behind for the window:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
DataContext = new ViewModelBase();
}
}
And the ViewModel:
public class ViewModelBase
{
public ViewModelBase()
{
_canExecute = true;
}
private ICommand _clickCommand;
public ICommand ClickCommand
{
get
{
return _clickCommand ?? (_clickCommand = new CommandHandler(() => MyAction(), _canExecute));
}
}
private bool _canExecute;
public void MyAction()
{
}
}
public class CommandHandler : ICommand
{
private Action _action;
private bool _canExecute;
public CommandHandler(Action action, bool canExecute)
{
_action = action;
_canExecute = canExecute;
}
public bool CanExecute(object parameter)
{
return _canExecute;
}
public event EventHandler CanExecuteChanged;
public void Execute(object parameter)
{
_action();
}
}
I hope this will give you the idea.
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