We have edit dialogs with editable fields on them, and we want to display a confirmation dialog if the user tries to close the edit dialog without saving. Simplified code to illustrate the issue: 

https://blazorrepl.telerik.com/GIEwwBvM54V6RbH952 

Sometimes we need custom filter logic. 

The advised approach currently is to use the OnRead event and have to manage the fetching of data manually  https://docs.telerik.com/blazor-ui/components/grid/manual-operations

If we could set a column to use a filter function  that has Func<GridDataType, Bool>? then we could apply this complex filter without having to repeatedly query the database and apply filters server side. 

For example, if I wanted to filter a column that related to an object that had a property that was a Collection<T> I could check the values of this collection against a filter UI I have made somewhere in the grid or outside of it. Then when the columns filterdescriptior was reviewed it would check my Func which returned True if any of the Rows Collection<T> matched my custom filter UI options.

Example use case that this feature would allow; 

For reasons unknown, our TelerikGrid rows all render with each <tr> element having the "k-alt k-table-alt-row" classes associated with them. This causes the background colour for each row to be the same, rather than alternating between two colours.

For example, the following block of code...

<TelerikGrid Id="@(Utility.CleanCssId("CrewGrid"))"
                 DetailTemplate="GridDetailTemplate"
                 EnableLoaderContainer="@ShowLoading"
                 Groupable="false"
                 Height="100%"
                 OnRead="@OnGridRead"
                 OnStateChanged="@OnGridStateChanged"
                 OnStateInit="@OnGridStateInit"
                 Pageable="true"
                 PageSize="@PageSize"
                 PageSizeChanged="@OnGridPageSizeChanged"
                 Reorderable="IsLargeScreen"
                 Resizable="IsLargeScreen"
                 SelectionMode="GridSelectionMode.Single"
                 ShowColumnMenu="IsLargeScreen"
                 Size="@GetGridSize"
                 Sortable="true"
                 SortMode="SortMode.Multiple"
                 TItem="CrewListItem"
                 @ref="Grid"
                 @bind-SelectedItems="@SelectedItems"
                 OnRowRender="OnRowRender">
    <NoDataTemplate>
        <strong>@RecordsMessage</strong>
    </NoDataTemplate>
    <GridSettings>
        <GridColumnMenuSettings Lockable="false" FilterMode="ColumnMenuFilterMode.None" />
        <GridPagerSettings InputType="PagerInputType.Buttons" PageSizes="@PageSizes" ButtonCount="5" Adaptive="false" Position="PagerPosition.Bottom" />
    </GridSettings>
    <GridColumns>
        <GridColumn Field="@nameof(CrewListItem.Color)"
                    Width="@(IsLargeScreen ? "40px" : "50px")"
                    Resizable="false"
                    ShowColumnMenu="false"
                    Groupable="false"
                    ShowColumnChooser="false"
                    Sortable="false"
                    HeaderClass="k-text-transparent"
                    OnCellRender="OnGridCellRender">
            <Template>
                @{
                    var item = (CrewListItem)context;
                    <M360ListColumnColor Color="@item.Color" IsLargeScreen="IsLargeScreen" />
                }
            </Template>
        </GridColumn>
        <GridColumn Field="@nameof(CrewListItem.Name)" Title="@TMessages.Crew" OnCellRender="OnGridCellRender" VisibleInColumnChooser="false">
            <Template>
                @{
                    var item = (CrewListItem)context;
                    <div class="k-d-flex k-h-full @(IsLargeScreen ? "k-align-items-stretch" : "k-align-items-center")">
                        <M360ListColumnLink Url="@string.Concat("crew/", item.Id)" Text="@item.Name" EntityType="Crew" IsPrimary="true" />
                    </div>
                }
            </Template>
        </GridColumn>
        <GridColumn Field="@nameof(CrewListItem.DivisionsJson)" Title="Division(s)" Sortable="true" Visible="IsLargeScreen" OnCellRender="OnGridCellRender">
            <Template>
                @{
                    var item = (CrewListItem)context;
                    <M360ListColumnList Items="@item.Divisions.ToList()" />
                }
            </Template>
        </GridColumn>
         .
         .
         .
    </GridColumns>
</TelerikGrid>

...results in markup like this...

<tbody class="k-table-tbody" role="rowgroup">
  <tr
    role="row"
    class="k-master-row k-table-row k-alt k-table-alt-row"
    data-render-row-index="0"
    aria-rowindex="1"
  >
    . . .
  </tr>
  <tr
    role="row"
    class="k-master-row k-table-row k-alt k-table-alt-row"
    data-render-row-index="1"
    aria-rowindex="3"
  >
    . . .
  </tr>
  <tr
    role="row"
    class="k-master-row k-table-row k-alt k-table-alt-row"
    data-render-row-index="2"
    aria-rowindex="5"
  >
    . . .
  </tr>
  . . .
</tbody>

I can see that the "aria-rowindex" increments by two, yet the "data-render-row-index" increments by one. Are we missing something simple, yet crucial here? What could cause the skipping of rows during render?

Many thanks,

Nem

Hi,

I haven't been able to find this as a request or as a topic of discussion (If it iss feel free to point me to it and close this request) but I feel the Grouping feature is limiting. If I use the group field in say the DropDownList the grouping works fine but it orders it alphabetically.

I propose adding a number of features to enhance this. The first being a GroupAscending or GroupDescending tag. Takes a boolean value and allows you to change the order to ascending (default/True) or descending (False).

The second, and more complicated feature upgrade could be a GroupOrder tag. This would take a List of the group field names ordered in the way you require and apply that order to the grouping in the DropDownList. for instance if you had the list ordered as Category 1, Category 3, Category 2 it would display the items in each grouping in that order top to bottom.

Regards,

Luke

Hi,
I have a little problem with changing the LoadGroupsOnDemand value. Depending on the data in my grid, I set this value to true or false. When updating grid data requires changing the LoadGroupsOnDemand value, I can't do it this way:

LoadGroupsOnDemand = true;
GridData = result;
GridRef.SetStateAsync(GridRef.GetState());

This code throws me an exception.
I need to do something like this to make it work:

LoadGroupsOnDemand = true;
GridRef.LoadGroupsOnDemand = LoadGroupsOnDemand;
GridData = result;
GridRef.SetStateAsync(GridRef.GetState());

This is the code that is executed in onclick. After OnRead is executed, the exception is thrown.

Let me know if you need more information.

See below repl

https://blazorrepl.telerik.com/GeYodYvp135zJH7N22

The first dropdown is populated correctly, it is not in a FormItem or Template

The second one, populated in the same way but inside a FormItem context does not show the data, it only redraws and shows data when entering another control i.e. the other working dropdown.

This was previously working when the application was using .net 6 and Telerik 3.6.1
It has since been updated to .net 8 and Telerik 5.1.1

What is the correct way to populate this?
Can you provide more information?

Thanks.

Currently using Telerik.DataSource.QueryableExtensions.CreateDataSourceResult() results in queryable.Count() + queryable.Skip(...).Take(...). done seperatelly. EF Core specific tests are already present it seems, based on decompiled code, I can see: "if (!sort.Any() && queryable.Provider.IsEntityFrameworkProvider())". 

Request: Add support for other ORM's that are more capable than EF Core. In case of pagination, window-function could be used to save from extra count query. A short sample bellow:

var dbResults = await queryable
	.Select(x => new {
		Item = x,
		TotalCount = Sql.Ext.Count().Over().ToValue()
	})
	.Skip(() => offset)
	.Take(() => limit)
	.ToListAsync();

var count = dbResults.FirstOrDefault()?.TotalCount ?? 0;
var items = dbResults.Select(x => x.Item);

Read more about Window functions: https://statics.teams.cdn.office.net/evergreen-assets/safelinks/1/atp-safelinks.html 

Hi,

Here is my demo DatePicker Demo

In Firefox, after I use the mouse to black all texts out, then DatePicker only selects the month field in the place holder. I expect to select all texts.

In Chrome or Edge, the DatePicker works as expected, after blacking texts out, it selects all texts in the place holder

Could you please check the issue?

Thanks and regards,

Tung

I just spent hours trying to understand why my grid did not work and threw a "source can't be null" exception at me when I set data to a 100% initialized - not null - list of a struct type.. Eventually I figured that the struct was the problem and turning it into a class fixed it, but that was just by chance.

Please for the sake of developer sanity give this a proper check.

Hi Telerik Team,

when using the (currently) latest versions of VS (17.11.0) and Blazor 8.0.8 runtimes (and custom css theme version 8.2.0) I get the following error when running my project in debug mode:

TypeError: Cannot read properties of null (reading 'classList')
Stapelüberwachung:
 >  at e.addClass (https://localhost:7038/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js:50:1122923)
 >    at v.resetCallout (https://localhost:7038/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js:50:1372516)
 >    at v.adjustCalloutPosition (https://localhost:7038/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js:50:1372355)
 >    at e.invokeComponentMethod (https://localhost:7038/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js:50:1112736)
 >    at https://localhost:7038/_framework/blazor.webassembly.js:1:2878
 >    at new Promise (<anonymous>)
 >    at b.beginInvokeJSFromDotNet (https://localhost:7038/_framework/blazor.webassembly.js:1:2835)
 >    at Object.vn [as invokeJSJson] (https://localhost:7038/_framework/blazor.webassembly.js:1:58849)
 >    at https://localhost:7038/_framework/dotnet.runtime.8.0.8.80cvijctdx.js:3:178428
 >    at Ll (https://localhost:7038/_framework/dotnet.runtime.8.0.8.80cvijctdx.js:3:179262)

It looks like the problem has something to do with a function that wants to set the css "k-callout-e" class to some object.
The problem appears in js when e is null in the following method:
e.classList.add(t)

In this case e = null and t = "k-callout-e". It seems there's no null check for e and VS 2022 reports the problem.

The debugger in VS cannot be disabled for js content as it seems it's the same debugger for Blazor itself.
When hitting F5 to continue multiple times the projects keeps running until it hits the same problem again.

In my project I added a single "TelerikTooltip" component for Tooltips. I tried disabling it but still the same problem.
Maybe the js code is used for some other component.

If you need more information just let me know.

Regards,
Tom

Hi, I just came accross a bug in the TelerikStepper.

I try to create a custom version that switches to a custom success icon after a step is completed.
It contains the following codesnippets:

<TelerikStepper Linear="true" ValueChanged="@HandleValueChanged">
    <StepperSteps>
        @for (int i = 0; i < IsValidArray.Length; i++)
        {
            <StepperStep Valid="@IsValidArray[i]"></StepperStep>
        }
    </StepperSteps>
</TelerikStepper>

@code {
    bool?[] IsValidArray = [null, null, null, null];

    public void HandleValueChanged(int index)
    {
        for (int i = 0; i < IsValidArray.Length; i++)
        {
            IsValidArray[i] = index > i ? true : null;
        }
    }
}

Forward it works like expected:

When moving backwards it behaves strange:

Except if you are debugging (Visual Studio debugger), then everything works as expected:

Same thing can be achived when not debugging but clicking on the step a second time.


This can not be solved by adding the @key parameter as suggested in https://feedback.telerik.com/blazor/1659827-bug-in-the-telerikstepper-in-blazor from Hristian Stefanov!

Nevertheless, it turns out that the Task.Delay(1); seems to solve the Issue somehow.

Is this intended?

Using Microsoft Visual Studio Professional 2022 (64-bit) - Current Version 17.11.0

Trying to create a new Telerik for Blazor project using Telerik C# Blazor Application Template.

Visual Studio freezes after I Name the project and click create. Only way to exit out of Visual Studio is to kill it through task manager.

Trying your project walk through for Blazor, RpsTrackingBlazor, After I add the nuget packages and try to add the using statement to _imports.razor as in the tutorial I get the error that the type or namespace name telerik could not be found.

Your project uses <TargetFramework>netcoreapp3.1</TargetFramework>

I also tried framework net8.0

Hi Team,

I am looking for captcha component to verify user as human like below screenshot. Please let me know if this feature is available

I recently had a breakthrough moment in my journey learning and using Telerik Blazor that I believe highlights a crucial area for improvement in your documentation strategy. I believe that this will significantly help me learn and use your components,  I suspect others may still fall into the same trap as me.  I'm confident that implementing this suggestion will make the learning process considerably easier for all users.

As a developer with over 35 years of experience, my initial approach to learning new technologies is to rely heavily on official documentation. I expect to find comprehensive resources that facilitate a smooth learning curve. However, after years of struggling with Telerik Blazor components, I stumbled upon the Component Demos section (https://demos.telerik.com/blazor-ui). This discovery, triggered by a specific Google search for "telerik blazor drawer submenu," is a game-changer.

The Component Demos contain a wealth of practical examples for each component, offering invaluable "cut-and-paste" starting points. Before this, I primarily relied on StackOverflow and other online resources and until today, I finally landed on the Telerik Blazor Component demos. The fact that I have been unaware of this resource for so long represents a significant shortcoming in the current documentation.  How easy it would be to add a link in the overview to the component's demos which would have saved me countless hours of trying to solve problems that have already been solved on the demos page, like the Drawer submenu mentioned above.

   Integrating direct links to each component's respective demo page within the main documentation would dramatically improve the discover-ability of these demos and empower users to independently solve many common challenges. Currently, the limited examples within the documentation are insufficient for comprehensive understanding.

In summary, prominently featuring the Component Demos within the core Telerik Blazor documentation would vastly enhance the learning experience, reduce support requests, and empower developers to utilize the full potential of your components.

Peter

When enabling/disabling a form element that is defined in a child component, the element is successfully disabled, however a console error occurs. The error occurs whether the child component makes the update or the parent makes the update through a passed parameter.  The error does not occur for form elements defined in the parent.  The error does not occur for basic html input elements defined in the child. 

Element definition:

<TelerikTextBox 
     Id="ElementMisc" 
     AutoComplete="new-password" 
     @bind-Value="@_searchModel.ElementMisc" 
     Enabled="!_elementSelectMode" 
     class="textbox-75"
     DebounceDelay="0">
 </TelerikTextBox>

Update Code defined in child:

 if (results.Data.Count > 1)
 {   
     _elementSelectMode= true;
     StateHasChanged();

 }

Console Error:

Uncaught (in promise) Error: Assertion failed - heap is currently locked
    at mr (blazor.web.js:1:158963)
    at Object.beginInvokeDotNetFromJS (blazor.web.js:1:157244)
    at w.invokeDotNetMethodAsync (blazor.web.js:1:3978)
    at C.invokeMethodAsync (blazor.web.js:1:5486)
    at r.invokeMethodAsync (telerik-blazor.js:22:1272553)
    at r.onBlur (telerik-blazor.js:22:1463592)
    at ye.setOrRemoveAttributeOrProperty (blazor.web.js:1:28630)
    at ye.applyAttribute (blazor.web.js:1:27574)
    at ye.applyEdits (blazor.web.js:1:24601)
    at ye.updateComponent (blazor.web.js:1:23606)

Within the grids, be able to filter and group using And & Or statements.  The following is our design.