How to detect events from an added template user control inside main form

Question

Having a user control template SubCtrl that gets an id on constructor to set a label CounterLabelText and consists on:

1 checkbox
1 button
1 RadNumeric

<Grid Height="27" Width="602">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="533*" />
            <ColumnDefinition Width="44*" />
        </Grid.ColumnDefinitions>
        <Label                          Margin="26,0,492,0" Content="{Binding CounterLabelText}" />
        <CheckBox                       Height="16" HorizontalAlignment="Left" Margin="7,5,0,0"     Name="ChkBxOrder"              Width="21" VerticalAlignment="Top"  telerik:StyleManager.Theme="Vista" IsManipulationEnabled="True" />
        <!--<telerik:RadButton          Height="22" HorizontalAlignment="Left" Margin="343,1,0,0"   Name="ButtonDoSomething"       Width="58" VerticalAlignment="Top"  telerik:StyleManager.Theme="Vista" Content="Set Points" Click="ButtonDoSomething_Click" />-->
        <telerik:RadNumericUpDown       Height="18" HorizontalAlignment="Left" Margin="412,1,0,0"   Name="radx"                    Width="40" VerticalAlignment="Top"  IsInteger="True" telerik:StyleManager.Theme="Vista"/>
    </Grid>




public partial class SubCtrl : UserControl
{
    private string _counterLabelText;
    public string CounterLabelText
    {
        get
        {
            return _counterLabelText;
        }
        set
        {
            _counterLabelText = value;
            OnPropertyChanged("CounterLabelText");
        }
    }

    public SubCtrl(int id)
    {
        InitializeComponent();
        CounterLabelText = id.ToString();
        DataContext = this;
    }
    #region INotifyPropertyChanged Members

    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
    #endregion
}

As user control is created dynamically on ADD button inside main form passing a counter like

public partial class MainCtrl : UserControl
{
    int templateRowsCounter;

    //constructor and variables
    //...
    //...
    private void AddTemplate_Click(object sender, RoutedEventArgs e)
    {
        StackRefinement.Children.Add(new SubCtrl (++templateRowsCounter));
    }

    private void DelTemplate_Click(object sender, RoutedEventArgs e)
    {
        //how to remove it based on templateRowsCounter ???
    }

}

I have two questions

1. How can I add remove last added template with DelTemplate_Click() ?
2. Having SubCtrl with a checkbox, a button and a radNumeric How can I know when ButtonDoSomething_Click() method must be called when pressing ButtonDoSomething, and also how to get state of checkbox and RadNumeric, I mean How to detect the events?

Answer 1

Update

SubCtrl class

• I added an event ButtonDoSomethingClicked
• added event handler to ButtonDoSomething.Click
• invoked ButtonDoSomethingClicked in the event handler

additionally I would prefer to use DependencyProperty instead of INotifyPropertyChanged when I am having UserControl as base class so modified CounterLabelText too

public partial class SubCtrl : UserControl
{
    public event EventHandler ButtonDoSomethingClicked;

    public string CounterLabelText
    {
        get { return (string)GetValue(CounterLabelTextProperty); }
        set { SetValue(CounterLabelTextProperty, value); }
    }

    // Using a DependencyProperty as the backing store for CounterLabelText.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty CounterLabelTextProperty =
        DependencyProperty.Register("CounterLabelText", typeof(string), typeof(SubCtrl), new PropertyMetadata(null));


    public SubCtrl(int id)
    {
        InitializeComponent();
        CounterLabelText = id.ToString();
        DataContext = this;
        ButtonDoSomething.Click += ButtonDoSomething_Click;
    }

    void ButtonDoSomething_Click(object sender, RoutedEventArgs e)
    {
        ButtonDoSomethingClicked.Invoke(this, EventArgs.Empty);
    }
}

code for the MainCtrl

• added event handler for ButtonDoSomethingClicked
• updated to use templateRowsCounter for deletion.

class code

public partial class MainCtrl : UserControl
{
    int templateRowsCounter;

    private void AddTemplate_Click(object sender, RoutedEventArgs e)
    {
        SubCtrl sub = new SubCtrl(++templateRowsCounter);
        sub.ButtonDoSomethingClicked += sub_ButtonDoSomethingClicked;
        StackRefinement.Children.Add(sub);
    }

    private void DelTemplate_Click(object sender, RoutedEventArgs e)
    {
        SubCtrl sub = (SubCtrl)StackRefinement.Children[--templateRowsCounter];
        sub.ButtonDoSomethingClicked -= sub_ButtonDoSomethingClicked;
        StackRefinement.Children.Remove(sub);
    }

    void sub_ButtonDoSomethingClicked(object sender, EventArgs e)
    {
        //your do something logic
    }
}

so this sample propogates up the ButtonDoSomethingClicked, rest can also be implemented in same way. ButtonBase.Click is also useful when you can not modify the code, also it is bit more generic approach.

previous

here is your quick solution for question 1

private void DelTemplate_Click(object sender, RoutedEventArgs e)
{
    //remove last added template, advisable to check if exists before deleting it
    StackRefinement.Children.RemoveAt(StackRefinement.Children.Count - 1);
}