Events
Templated Picker for Xamarin exposes a SelectionChanged event which is raised when the user confirms the selected item.
Example
<telerikInput:RadTemplatedPicker SelectionChanged="RadTemplatedPicker_SelectionChanged" x:Name="picker">
<telerikInput:RadTemplatedPicker.SelectorTemplate>
<ControlTemplate>
<telerikInput:RadCalendar SelectedDate="{TemplateBinding SelectedValue, Mode=TwoWay}"/>
</ControlTemplate>
</telerikInput:RadTemplatedPicker.SelectorTemplate>
</telerikInput:RadTemplatedPicker>
and the SelectionChanged event, where the sender is the RadTemplatedPicker control
private void RadTemplatedPicker_SelectionChanged(object sender, System.EventArgs e)
{
// implement your logic here
}