Questions on UI for WPF Forum

1 answer

34 views

Bug: NullReferenceException raised by IGridViewEditor.SetText in DateTimePickerGridViewEditor when typing a key into a GridViewDataColumn that contains a collapsed RadDateTimePicker

Is this the best place to report bugs?

This is with 2024.4.1213.462.

To duplicate the issue:

With VS 2022, create a WPF (.NET Framework) application,
Delete MainWindow.xaml and MainWindow.xaml.cs
Unzip the attached file, place MainWindow.xaml and MainWindow.xaml.cs from the zip where the old files were or use the pasted text below
Build and run the application
Put focus on a cell in a row in the grid and type a letter

Expect the following exception to be raised

	Name	Value	Type
◢	$exception	{"Object reference not set to an instance of an object."}	System.NullReferenceException

at Telerik.Windows.Controls.DateTimePickerGridViewEditor.Telerik.Windows.Controls.GridView.IGridViewEditor.SetText(String text) in Telerik.Windows.Controls\DateTimePickerGridViewEditor.cs:line 56

In case the zip doesn't work:

MainWindow.xaml.cs:

namespace WpfApp14
{
    using System;
    using System.ComponentModel;
    using System.Windows;
    using System.Collections.ObjectModel;

    public sealed class GridValueViewModel : INotifyPropertyChanged
    {
        private string someValue = string.Empty;

        public GridValueViewModel(string someValue)
        {
            this.SomeValue = someValue;
        }

        public event PropertyChangedEventHandler PropertyChanged;

        public string SomeValue
        {
            get
            {
                return this.someValue;
            }

            set
            {
                value = value ?? string.Empty;
                if (this.SomeValue != value)
                {
                    this.someValue = value;
                    this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(this.SomeValue)));
                }
            }
        }

        public DateTime? DateValue
        {
            get
            {
                if (DateTime.TryParse(this.SomeValue, out var value))
                {
                    return value;
                }

                return null;
            }

            set
            {
                if (value == null)
                {
                    this.SomeValue = string.Empty;
                    return;
                }

                this.SomeValue = value.ToString();
            }
        }

        public ObservableCollection<string> SomeValueItems { get; } = new ObservableCollection<string>(
            new[]
            {
                "cat",
                "dog",
                "bird"
            });
        
    }

    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            this.InitializeComponent();
            this.DataContext = this;
        }

        public ObservableCollection<GridValueViewModel> Values { get; } = new ObservableCollection<GridValueViewModel>(
            new[]
            {
                new GridValueViewModel("cat"),
                new GridValueViewModel("dog"),
                new GridValueViewModel("bird")
            });
    }
}

MainWindow.xaml:

<Window x:Class="WpfApp14.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <telerik:RadGridView
        AutoGenerateColumns="False"
        ItemsSource="{Binding Values, Mode=OneWay}">
        <telerik:RadGridView.Columns>
            <telerik:GridViewDataColumn
                Header="Column 1">
                <telerik:GridViewDataColumn.CellTemplate>
                    <DataTemplate>
                        <Label
                            Content="{Binding SomeValue}" />
                    </DataTemplate>
                </telerik:GridViewDataColumn.CellTemplate>
                <telerik:GridViewDataColumn.CellEditTemplate>
                    <DataTemplate>
                        <Grid>
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition
                                    Width="*" />
                            </Grid.ColumnDefinitions>
                            <TextBox
                                Grid.Column="0"
                                Text="{Binding SomeValue, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}"
                                Visibility="Collapsed" />
                            <telerik:RadComboBox
                                Grid.Column="0"
                                HorizontalAlignment="Stretch"
                                IsEditable="False"
                                ItemsSource="{Binding SomeValueItems}"
                                SelectedItem="{Binding SomeValue}" />
                            <telerik:RadDateTimePicker
                                Grid.Column="0"
                                HorizontalAlignment="Stretch"
                                InputMode="DatePicker"
                                DateTimeWatermarkContent="{x:Null}"
                                SelectedValue="{Binding DateValue, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}"
                                Visibility="Collapsed" />
                        </Grid>
                    </DataTemplate>
                </telerik:GridViewDataColumn.CellEditTemplate>
            </telerik:GridViewDataColumn>
        </telerik:RadGridView.Columns>
    </telerik:RadGridView>
</Window>

DateTimePicker

GridView

answered on 07 Aug 2025

0 answers

25 views

Filter on CalculatedItem

Hello,

is there a possibility to create a Value Filter or some sort of filtering on a CalculatedItem (https://docs.telerik.com/devtools/wpf/controls/radpivotgrid/features/localdatasourceprovider/local-calc-items)?

Best

Simon

PivotGrid

asked on 01 Aug 2025

1 answer

43 views

Add a custom palette with its own name in a Telerik RadColorPicker

Hello, I want to add a custom palette with its own names and colors in WPF. But seems like I can only work with built-in MainPalette, HeaderPalette, AdditionalContent

The image below shows my intention. I want to add not only 2 of them, but as many as I want.

ColorPicker

answered on 29 Jul 2025

1 answer

37 views

EditMask With DateTimePicker

Is there a way to use RadMaskedDateTimeInput with RadDateTimePicker? Users want to be able dates in MM/dd/yyyy format (without typing the slashes) or use the calendar picker. I believe RadDateTimePicker uses RadWatermarkTextBox which does not have tight input control.

DateTimePicker

answered on 29 Jul 2025

0 answers

38 views

WPF Diagram Export to pdf,shape border deformation

When adding a graphic to the diagram, adjust its width and height, and set the border to 2（or other value）

After exporting the PDF, the thickness of each border is inconsistent.At the same time, the thickness of the border is also different from the set value,I feel like the border has been stretched and enlarged as a whole,You can test Microsoft Visio, it doesn't have this issue.

Test code use the sample sdk project:ExportToPDF_WPF

Please refer to the image

Diagram

updated question on 25 Jul 2025

0 answers

52 views

Subject: RadDatePicker Calendar Popup Shows Today's Date Instead of SelectedDate in Test Environment

Product: Telerik UI for WPF

Control: RadDatePicker (custom inherited as NewDatePicker)

Target Framework: .NET Framework 4.7

Issue Summary:

W're facing an inconsistency in behavior with the RadDatePicker control between development and test environments.

We have a custom control NewDatePicker that inherits from RadDatePicker.
At runtime, we bind a SelectedDate value (e.g., Jan 23, 2025) to the control.
When the user clicks to open the calendar popup:
- In development, the calendar popup correctly opens to SelectedDate.
- In test, the calendar popup opens to today's date (July 2025) instead of the bound SelectedDate.

Steps to Reproduce:

Use a RadDatePicker or inherited control.

2. Set SelectedDate = DateTime.Now.AddMonths(-6) (e.g., Jan 23, 2025).

3. Run the application and open the DatePicker calendar.

4. Observe the calendar view:

Dev: shows January 2025 (as expected).
Test: jumps to current date (July 2025), even though SelectedDate is Jan 23.

What We Tried:

Manually calling this.DisplayDate = this.SelectedDate.Value; inside OnPreviewMouseDown.
Using Dispatcher.BeginInvoke(..., DispatcherPriority.Loaded) to defer the update.
Accessing and setting PART_Calendar.DisplayDate explicitly.
Ensured that SelectedDate has a valid value.
Tried handling Loaded, OnApplyTemplate, and custom SyncDisplayDate() method.
Everything works well in development — but not in the test environment.

Questions:
1. Is there a recommended approach to ensure the calendar opens to the correct month consistently in all environments?

Note: In Test environment First time click that time its show the current Date secound time I click that time it show the expected output.

the below the calendar need to show the 23 jan 2025 but its show current date.

DatePicker

updated question on 24 Jul 2025

2 answers

35 views

Turn off Ctrl-Mouse Wheel zooming

Is there anyway to disable this functionality in the pdf viewer so that I can handle zooming manually?

PDFViewer

answered on 22 Jul 2025

0 answers

59 views

Simple Word Document Crashes WPF RadRichTextBox

I am using Telerik UI for WPF 2024 Q4\Binaries.NoXaml\WPF80\Telerik.Windows.Documents.Flow.FormatProviders.Doc.dll (version 2024.4.1106.60) on Windows 11 Pro (24H2). The program is developed using VS 2022.

It simply tries to load and display the attached DOCX file and the component crashes during layout with a null reference exception.

         using var instream = File.OpenRead(path);

         var openXmlRadDocProvider =
            new Telerik.Windows.Documents.FormatProviders.OpenXml.Docx.DocxFormatProvider();

         var raddoc = openXmlRadDocProvider.Import(instream);
         RadRtb.Document = raddoc;

Word displays this perfectly. Trying to determine if this is a Telerik bug or a "me" problem.

Stenly replied and said he was unable to reproduce using 2025.2.707. I am able to reproduce the crash with that version. I have attached my project in case I'm doing something wrong in code.

Thanks.

-John Reilly.

RichTextBox

updated question on 16 Jul 2025

1 answer

121 views

Setting a font size for the entire application

I am using the Material Theme, here's my app.xaml code

<Application x:Class="Desktop_Application.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Application.Resources>
        
        <ResourceDictionary>
            <!-- Global default font size -->
            <Style TargetType="{x:Type Control}">
                <Setter Property="FontSize" Value="8"/>
            </Style>
            
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/System.Windows.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.Chart.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.Data.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.FixedDocumentViewers.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.GridView.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.ImageEditor.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.Input.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.Navigation.xaml"/>
                <ResourceDictionary Source="/Telerik.Windows.Themes.Material;component/Themes/Telerik.Windows.Controls.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

However, the application does not reflect the new font size, is there a way to do it?

General Discussions

answered on 16 Jul 2025

0 answers

61 views

Update problem with some telerik packages

I'm using central package management, where my Directory.Build.props has folliwing entries:

<ItemGroup>
    <PackageVersion Include="Telerik.UI.for.Wpf.NetCore.Xaml" Version="2024.1.423" />
    <PackageVersion Include="Telerik.Windows.Controls.Data.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.DataVisualization.for.Wpf.Xaml" Version="2024.3.924" />
    <PackageVersion Include="Telerik.Windows.Controls.Diagrams.Extensions.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.Diagrams.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.Diagrams.Ribbon.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.GridView.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.Input.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.Navigation.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Controls.RibbonView.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Data.for.Wpf.Xaml" Version="2025.2.707" />
    <PackageVersion Include="Telerik.Windows.Diagrams.Core.for.Wpf.Xaml" Version="2025.2.707" />
</ItemGroup>

As you can maybe see,

Telerik.UI.for.Wpf.NetCore.Xaml has 2024.1.423
Telerik.Windows.Controls.DataVisualization.for.Wpf has 2024.3.924

when using the manage nuget packages dialog from within visual studio it does not report that any updates are necessary, but the build tells me that (of course) there is a version mismatch,

The dialog even tells me that there is a newer version:

What could be the problem that it doesn't get updated or is not found to require an update?

General Discussions

updated question on 15 Jul 2025