Last Updated: 06 Dec 2021 14:44 by ADMIN

If you enter a format with a 24 hour time( Format="dd MMM yyyy HH:mm:ss")  for the Timepicker

If you enter the same format for the DateTimePicker the TimePicker in the DateTimePicker looks like this:


It seems like this is a bug as the only way I can change the DateTimePicker time UI is to alter my language/culture whereas the TimePicker displays correctly based on my format. 




Last Updated: 03 Dec 2021 10:40 by ADMIN
Selected items are not preserved when loading the state when the component is bound to ExpandoObjects
Last Updated: 02 Dec 2021 12:23 by ADMIN

I have a ComboBox/DropDownList that gets data from a remote service, using virtualization. When the PageSize property is big enough (in my case 20), I have issues scrolling up the selection box dropdown list. I'm trying to scroll but then resets to the currently selected item making it almost impossible to scroll up. You can use your own demo examples to replicate this issue.

To reproduce the issue, try the ComboBox - Virtualization, in Telerik REPL (Demo), change the PageSize from 10 to 20. Open the dropdown and select an item. Then, open again the dropdown and scroll slowly up.

Last Updated: 01 Dec 2021 17:19 by ADMIN

It looks like when the applied culture uses comma as decimal separator, the floating-point parsing is not successful and the StartValueChanged and EndValueChanged are not triggered.

They should fire on start or end value change regardless of the used culture.

Last Updated: 01 Dec 2021 16:16 by ADMIN
If the Multiselect has items selected and is not focused, clearing one item does not focus the component while clearing all items does. Deselecting single item should focus the component as well.
Last Updated: 29 Nov 2021 12:05 by ADMIN

Here is the problem or bug I would like you to look at: If the percent entry component that is in the test application is not in an EditorTemplate, then the OnFocusOut event will fire in Firefox when the Tab or Enter keys is pressed. When the component is within an EditorTemplate, the OnFocusOut event does not fire in Firefox for the Tab/Enter key. This leads me to believe that it is a bug in the Grid and Treelist that is blocking that event from firing in Firefox.

Steps to reproduce:

  1. Run the attached project in Firefox.
  2. Change one value in percent and press Tab
  3. Open the same page in Chrome and repeat

---------------------ADMIN EDIT---------------------

There is one way you can use here to avoid manipulating the onfocusout event to handle percentage input. You can create in your model two properties/values. One value for visualization, with a custom format to represent percentage. Another value to pass along to the business logic, that has the actual fraction. You can see a reference to the described approach in this REPL link.

Last Updated: 26 Nov 2021 12:58 by ADMIN
Created by: Eli
Comments: 1
Category: Editor
Type: Bug Report

When you paste a table in the Editor or insert one through the InsertHTML tool, the Editor adds two  <tbody> tags making this invalid HTML.

If you include a table in the initially rendered content (not pasting it afterwards), two <tbody> tags appear as well.

If you create table using the Create Table tool this behavior is not present, only one <tbody> tag is added as expected.

Last Updated: 24 Nov 2021 09:14 by ADMIN
Field and Value properties from GridCommandEventArgs don't populate in Incell editing. Their value is always null and thus I cannot get information for the edited field.
Last Updated: 22 Nov 2021 14:24 by ADMIN
Loading Groups on Demand in a column with a nullable data type groups all records under the "Null" group
Last Updated: 22 Nov 2021 11:35 by ADMIN
I have a record with id 1. In the OnEdit event, we check if the Edited item has Id == 1 and if so we cancel the edit. Now, the UI, if the Grid is in Read mode (not in Edit) clicking on the Grid cell that has Id == 1 does not trigger the edit, thus the editor is not rendered. On the other hand, if we open a previous cell that is editable and we click enter (tab) multiple times the non-editable cell will enter Edit mode and the editor is rendered.
Last Updated: 19 Nov 2021 13:45 by ADMIN
Created by: Gary
Comments: 0
Category: Grid
Type: Bug Report
The value provided to the Id parameter of the GridCommandButton is not rendered in the HTML. For reference, the TelerikButton renders its Id value.
Last Updated: 19 Nov 2021 08:56 by ADMIN


I have found a bug with the TelerikNumericTextBox in that it doesn't function correctly with nullable types (at least it doesn't with Nullable<int>). I have confirmed this is the case for both 2.28 and 2.29 versions of Kendo for Blazor.

Description of the issue:

If "TelerikNumericTextBox" is "@bind-Value" to a nullable int, the control exhibits some unusual behaviour. If you manually type 0 into the control, it is accepted and the value updates the view-model property. However, if you use either the down-arrow button or arrow keys to select 0 (on a fresh load so there is no existing value selected/set), it does not set/update the view-model property. However, it does work correctly if you select another value first (such as 1) and then select 0.

Unfortunately, this is confusing the end-users of my application and I believe it is a bug (I haven't noticed this when using the Kendo for Angular or Kendo for JQuery).

In my application, I need users to be able to set the value of 0 but we do not want to set an initial value for the NumericTextBox to be 0 as this could lead our customers on; the application in question is requiring the end-user to manually select the number rather than allowing them to just leave it as default. Therefore, the view-model property I am binding to has been put as "int?" so that the default value is null and validation will require the user to select a valid value if they just try and press save without making any changes. Please note, for our use case, the number 0 is a valid option!

Steps to reproduce the issue:

Use the following razor HTML

The new value is: @TheValue

<TelerikNumericTextBox Format="D" Max="10" Min="0" Step="1" @bind-Value="@TheValue"></TelerikNumericTextBox>

@code {
    public int? TheValue { get; set; }

Click into the control and either press "down" on the keyboard arrow keys or press the "down" icon next to the control, so the value is set to be 0. The number 0 will not be set/persisted to the view-model property even though the control shows a 0 value.

If you have multiple controls on the page, following the above steps will mean that as soon as you click into another control, 0 is deleted (I believe because the VM prop has not been set), this does not happen if you type 0 into the control.


If you continue to use the same Razor code above and any of the following workflows, it will set the controls view-model property correctly:

  • Type 0 into the control - value is set correctly and property on the view-model is updated
  • Select "up" on the keyboard (so the value is 1) and then press down (so the value is 0) - 0 is set correctly and property on the view-model is updated
  • Select "up" on the numeric textbox's up arrow button (so the value 1) and then press "down" on the down arrow button (so the new value is 0) - 0 is set correctly and property on the view-model is updated

Additional notes:

  • I have noticed this only seems to apply to the nullable version of the int type, if the prop is just an int, the control works fine but is automatically defaulted to 0 (which is not appropriate for my use case)
  • It seems that as soon as the control/view model property has an initial value, the control behaves normally and the issue no longer happens anymore (both with keyboard navigation and the control's up/down buttons).
  • I have not tested with any other types/primitives, just on INT so far
  • I have confirmed this happens if you have the control in an "<EditForm/>" or outside of an EditForm. 

I have attached a sample project where I have replicated the issue, it is just a simple NET5 WASM Blazor project (generated from the default template) and I have just added the latest Kendo for Blazor. Nothing else has been done except for demoing on the "index.razor" both binding approaches I have tried/been able to replicate this issue on.


I hope the above makes sense, let me know if you need any further clarification.

Last Updated: 18 Nov 2021 12:45 by ADMIN
When you use Virtual Scrolling you cannot control the scroll position with the Skip parameter if the data is received after initializing the GridState.
Last Updated: 15 Nov 2021 13:59 by ADMIN
Created by: Denver
Comments: 0
Category: DropDownList
Type: Bug Report
On a tablet, when the DropDownList, the MultiSelect or the ComboBox components are clicked, any appearance or disappearance of the tablet keyboard will cause them to display an empty popup.

This only happens if the popup somehow could otherwise overflow the viewport, i.e. only when the DropDownList, the MultiSelect or the ComboBox component are very close to the bottom of the viewport.
Last Updated: 15 Nov 2021 12:20 by ADMIN
When you use RowTemplate and Virtual Scrolling you cannot control the scroll position with the Skip parameter when the Grid state is initialized.
Last Updated: 10 Nov 2021 16:13 by ADMIN
Created by: Chris
Comments: 0
Category: Splitter
Type: Bug Report

When trying to drag/resize the splitter to the sides on a touch screen, you are only able to move the splitter a little bit before the whole screen starts moving.

To reproduce, go to the splitter demo (Blazor Splitter Demos - Overview | Telerik UI for Blazor), open the inspector, and change the view to a mobile device. I tested specifically on the iPad option.

I've tested the behavior on an Amazon Fire 10, One Plue 8T, and a Google Pixel 4, and all 3 of them have displayed the behavior. I also tested on a 7th gen Ipad (in safari) and found the control did indeed work as expected there.

Last Updated: 01 Nov 2021 10:39 by ADMIN

The following knowledge base article describes how to select the default value in a drop down, but if there's no default value the selection is not cleared using this method.


When setting the bind value to null (or the default, or frankly anything that doesn't exist in the drop down) I'd like the drop down list selection to be cleared when there's no default value set on the DropDownList.


@page "/"

<br />

<TelerikButton OnClick="@ClearSelection">Clear selection</TelerikButton>
<TelerikDropDownList Data="@data" @bind-Value="selectedValue" />

@code {
    List<string> data = new() { "selection" };
    string selectedValue;

    void ClearSelection()
        // This does not cause the drop down to clear the selection and I think it should.
        selectedValue = null;

Last Updated: 21 Oct 2021 14:35 by ADMIN
Create a page that hosts a TreeView with checkbox selection inside a TelerikWindow. Provide an initially checked item and navigate to this page. When it renders the checkbox is not in a checked state. 
Last Updated: 20 Oct 2021 13:26 by ADMIN

When using the TelerikCheckBoxListFilter component in a FilterMenuTemplate, it does render a checkbox with a blank label, but selecting it does not generate a filter descriptor.

For reference, the built-in CheckBoxList filtering correctly filters null values.

Last Updated: 19 Oct 2021 14:23 by ADMIN

I want to apply some custom CSS to hide the disabled dates. However, it appears that k-state-disabled class is not applied to all of them. 

For example, if I set the Max parameter to October 15th 2021, the remaining dates of October have the k-state-disabled but the ones in November only have k-other-month class.


The same behavior occurs when I set the Min parameter - the dates from the previous month do not have k-state-disabled class.




Note: This bug also affects Calendar, DateRangePicker and DateTimePicker components.

As a workaround for the time being you might try another approach - all the disabled cells have aria-disabled = "true" attribute which you can use as a CSS selector to target the disabled cells:

    [aria-disabled="true"] {
        visibility: hidden;

<TelerikDatePicker @bind-Value="datePickerValue" Max="@MaxValue"></TelerikDatePicker>

@code  {
    DateTime datePickerValue { get; set; } = new DateTime(2021, 10, 1);
    DateTime MaxValue { get; set; } = DateTime.Now;


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