XAML event handler in a nonroot object - xaml

Question

Imagine the following XAML:
<Page
x:Class="MyProject.MainPage"
xmlns:local="using:MyProject">
<local:MyStackPanel>
<Button Content="Go" Click="OnGo"/>
</local:MyStackPanel>
</Page>
XAML assumes that OnGois a method in the page class. Can I somehow tell it declaratively that OnGo resides in MyStackPanel instead?
I know I can assign the event handler programmatically once the page is loaded. I'm wondering if it's possible by purely XAML means. "No" is an acceptable answer :)

Answer 1

For your requirement, you could bind the MyStackPanel DataContext with itself. Then create BtnClickCommand that used to bind button command in the MyStackPanel class like following.
public class MyStackPanel : StackPanel
{
public MyStackPanel()
{
}
public ICommand BtnClickCommand
{
get
{
return new RelayCommand(() =>
{
});
}
}
}
public class RelayCommand : ICommand
{
private readonly Action _execute;
private readonly Func<bool> _canExecute;
/// <summary>
/// Raised when RaiseCanExecuteChanged is called.
/// </summary>
public event EventHandler CanExecuteChanged;
/// <summary>
/// Creates a new command that can always execute.
/// </summary>
/// <param name="execute">The execution logic.</param>
public RelayCommand(Action execute)
: this(execute, null)
{
}
/// <summary>
/// Creates a new command.
/// </summary>
/// <param name="execute">The execution logic.</param>
/// <param name="canExecute">The execution status logic.</param>
public RelayCommand(Action execute, Func<bool> canExecute)
{
if (execute == null)
throw new ArgumentNullException("execute");
_execute = execute;
_canExecute = canExecute;
}
/// <summary>
/// Determines whether this RelayCommand can execute in its current state.
/// </summary>
/// <param name="parameter">
/// Data used by the command. If the command does not require data to be passed,
/// this object can be set to null.
/// </param>
/// <returns>true if this command can be executed; otherwise, false.</returns>
public bool CanExecute(object parameter)
{
return _canExecute == null ? true : _canExecute();
}
/// <summary>
/// Executes the RelayCommand on the current command target.
/// </summary>
/// <param name="parameter">
/// Data used by the command. If the command does not require data to be passed,
/// this object can be set to null.
/// </param>
public void Execute(object parameter)
{
_execute();
}
/// <summary>
/// Method used to raise the CanExecuteChanged event
/// to indicate that the return value of the CanExecute
/// method has changed.
/// </summary>
public void RaiseCanExecuteChanged()
{
var handler = CanExecuteChanged;
if (handler != null)
{
handler(this, EventArgs.Empty);
}
}
}
Usage
<local:MyStackPanel DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<Button Command="{Binding BtnClickCommand}" Content="ClickMe" />
</local:MyStackPanel>