RadNumericUpDown non-visible initial value when initially focused by FocusManager.FocusedElement="{Binding ..}"

[Ian Verona]

I have an issue where the initial value of a RadNumericUpDown is not visible, when focused by FocusManager.FocusedElement in xaml.

If FocusManager is removed or you tab out of the input-field, the value showed correctly.

A little bug, but big usability-impact in our application.

Telerik version: 2014.3.1021.40
Visual Studio version: Premium 2012

Screendump attached.
I have a small POC app if required.

[Kalin]

Hello Ian,

Can you please share some sample code that demonstrates the exact implementation as I was not able to reproduce the described issue?

I'm looking forward to hearing from you.

Regards,
Kalin
Telerik

 

 

[Ian Verona]

Hi Kalin.

Thanks for your response. 
I can only attach images, so I'll paste code here :)

Xaml:

<Window x:Class="RadNumericTextBoxFocusTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerik="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Input"
        Title="MainWindow" Height="350" Width="525"
        FocusManager.FocusedElement="{Binding ElementName=UpDown}">
    <Grid>
        <StackPanel>
            <telerik:RadNumericUpDown
                Minimum="1"
                Maximum="20"
                Value="{Binding SomeInt, UpdateSourceTrigger=PropertyChanged}"
                Name="UpDown"/>
            <TextBox />
        </StackPanel>
    </Grid>
</Window>

Code behind:

/// <summary>
   /// Interaction logic for MainWindow.xaml
   /// </summary>
   public partial class MainWindow : Window
   {
       public MainWindow()
       {
           InitializeComponent();
       }

       protected override void OnInitialized(EventArgs e)
       {
           base.OnInitialized(e);

           DataContext = new Aclass() {SomeInt = 10};
       }


   }

   public class Aclass : ViewModelBase
   {
       private int _someInt;

       public int SomeInt
       {
           get { return _someInt; }
           set
           {
               _someInt = value;
               OnPropertyChanged(() => SomeInt);
           }
       }
   }

Thanks in advance.

/Ian V. Andersen

[Kalin]

Hello Ian,

The observed behavior is caused by the fact that the NumericUpDown gets focused before the DataContext is set. In order to get it working correctly you can set the DataContext above InitializeComponent:

public MainWindow()
{
    DataContext = new Aclass() { SomeInt = 10 };
    InitializeComponent();
}

Hope this helps.

Regards,
Kalin
Telerik