Further Environment Informations

Component: @progress/kendo-angular-treeview
Severity: regression (worked in v23, broken in v24)

rxjs: 7.8.2

zone.js 0.15.1 (zone-based, not zoneless)

typescript 6.0.3

Summary

When a flat [nodes] array is bound to kendo-treeview and the array reference is replaced after the first change-detection pass, the TreeView keeps rendering the initial nodes and never reflects the new data. In v23.x the same binding updated correctly.

Minimal reproduction (standalone, drop into a blank Angular 22 app / StackBlitz)

import { Component, signal } from '@angular/core';
import { bootstrapApplication } from '@angular/platform-browser';
import { TreeViewModule } from '@progress/kendo-angular-treeview';

interface Node { name: string; }

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [TreeViewModule],
  template: `
    <button (click)="replaceNodes()">Replace nodes</button>

    <p>Plain list (control — reflects the current data):</p>
    <ul>
      @for (n of nodes(); track n.name) { <li>{{ n.name }}</li> }
    </ul>

    <p>Kendo TreeView (bug — stays on the initial data):</p>
    <kendo-treeview
      [nodes]="nodes()"
      textField="name"
      [kendoTreeViewSelectable]="{ enabled: false }"
    >
      <ng-template kendoTreeViewNodeTemplate let-dataItem>
        {{ dataItem.name }}
      </ng-template>
    </kendo-treeview>
  `,
})
export class AppComponent {
  protected readonly nodes = signal<Node[]>([{ name: 'A' }, { name: 'B' }]);
  protected replaceNodes(): void {
    this.nodes.set([{ name: 'X' }, { name: 'Y' }, { name: 'Z' }]);
  }
}

bootstrapApplication(AppComponent).catch(err => console.error(err));

Steps to reproduce

1. Load the component — TreeView renders A, B.
2. Click Replace nodes (assigns a brand-new array [X, Y, Z]).

Expected

The TreeView re-renders and shows X, Y, Z (like the plain <ul> control right above it, which updates correctly — proving the data really changed and change detection ran).

Actual (v24.2.2)

The TreeView still shows A, B. The new [nodes] reference is ignored.

Regression

Identical code updated correctly on @progress/kendo-angular-treeview 23.x. It broke on the upgrade to 24.x. Bisecting across 24.0.0 → 24.2.2 would pinpoint the exact patch.

Current workaround

Force the TreeView to be destroyed and recreated whenever the data reference changes:
@for (nodes of [data()]; track nodes) {
  <kendo-treeview [nodes]="nodes" textField="name" ...>...</kendo-treeview>
}
This works but is obviously undesirable (full teardown/rebuild on every data change, loss of internal state).

Hi,

This works with Angular 20, must be a change related to that.

If I assign data to the TreeView synchronously, it works, but e.g. in a setTimeout, it doesn't any more. (I assign the full array, change detection is set to eager.)

Reproduction can be found here: https://codesandbox.io/p/devbox/mutable-glade-39twhs?workspaceId=ws_P4gPDf6RC2r5W8xExWQehV

Best regards,
Michael

`@progress/kendo-intl` incorrectly formats timezone offsets whose minute component is non-zero.

For example, a JavaScript `Date` with the historical Warsaw offset `UTC+01:24` is formatted as `+01:04` instead of `+01:24`.

This affects all tested `Z`, `X`, and `x` timezone format variants.

Environment

- `@progress/kendo-angular-intl`: `24.2.0`
- `@progress/kendo-intl`: `3.2.1`

- Browser/Node timezone: `Europe/Warsaw`
- Operating system: Windows
- Format: `yyyy-MM-ddTHH:mm:ssZZZZZ`

The same formatting implementation appears in `@progress/kendo-intl` versions `3.1.2` and `3.2.1`.

Reproduction

const { formatDate } = require('@progress/kendo-intl');

process.env.TZ = 'Europe/Warsaw';

const date = new Date(1900, 0, 1, 16, 0, 0);

console.log(date.toString());
console.log(date.getTimezoneOffset());
console.log(formatDate(date, 'yyyy-MM-ddTHH:mm:ssZZZZZ'));

Actual Result

Mon Jan 01 1900 16:00:00 GMT+0124
-84
1900-01-01T16:00:00+01:04

Expected Result

1900-01-01T16:00:00+01:24

Date#getTimezoneOffset() returns -84, meaning the local timezone is 84 minutes ahead of UTC:

84 minutes = 1 hour 24 minutes

Other Examples

The issue is not limited to positive offsets:

UTC is also formatted differently depending on the token, but that behavior may be intentional:

Tested Format Specifiers

All applicable format variants use the same incorrect minute calculation:

Z      -> +0104
ZZ     -> +0104
ZZZ    -> +0104
ZZZZ   -> GMT+01:04
ZZZZZ  -> +01:04

X      -> +0104
XX     -> +0104
XXX    -> +01:04
XXXX   -> +0104
XXXXX  -> +01:04

x      -> +0104
xxx    -> +01:04
xxxxx  -> +01:04

Changing from ZZZZZ to XXXXX or XXX therefore does not resolve the problem.

Suspected Root Cause

The current formatter appears to perform approximately this calculation:

const offset = date.getTimezoneOffset() / 60;
const hoursMinutes = Math.abs(offset).toString().split('.');
const minutes = hoursMinutes[1] || 0;

For an 84-minute offset:

84 / 60 = 1.4

The decimal portion "4" is then treated as four minutes and padded to "04".

However, the fractional part represents a fraction of an hour:

0.4 hours * 60 = 24 minutes

Likewise, for 210 minutes:

210 / 60 = 3.5

The formatter produces 03:05, although 0.5 hours is 30 minutes.

Suggested Fix

Timezone offsets should remain integer minute values throughout formatting:

function formatTimeZone(date, info, options) {
    const totalMinutes = date.getTimezoneOffset();
    const absoluteMinutes = Math.abs(totalMinutes);
    const hours = Math.floor(absoluteMinutes / 60);
    const minutes = absoluteMinutes % 60;
    const sign = totalMinutes <= 0 ? '+' : '-';

    // Continue applying shortHours, separator, optionalMinutes,
    // localizedName and zZeroOffset options using hours and minutes.
}

The important calculations are:

const hours = Math.floor(Math.abs(offsetMinutes) / 60);
const minutes = Math.abs(offsetMinutes) % 60;

Converting the offset to a decimal hour and splitting its string representation is not reliable.

Suggested Regression Tests

it('formats a positive timezone offset with minutes', () => {
    const date = new Date(2024, 5, 25, 12, 7, 5);
    vi.spyOn(date, 'getTimezoneOffset').mockReturnValue(-84);

    expect(formatDate(date, 'yyyy-MM-ddTHH:mm:ssZZZZZ'))
        .toBe('2024-06-25T12:07:05+01:24');
});

it('formats a negative timezone offset with minutes', () => {
    const date = new Date(2024, 5, 25, 12, 7, 5);
    vi.spyOn(date, 'getTimezoneOffset').mockReturnValue(210);

    expect(formatDate(date, 'yyyy-MM-ddTHH:mm:ssZZZZZ'))
        .toBe('2024-06-25T12:07:05-03:30');
});

Other useful cases include:

-345 -> +05:45
-330 -> +05:30
210 -> -03:30
0 -> Z or +00:00, depending on the selected token

Impact

This can corrupt serialized date-time values when they are passed to systems that honor the emitted offset, including .NET DateTimeOffset.

Example:

Intended: 1900-01-01T16:00:00+01:24
Emitted:  1900-01-01T16:00:00+01:04

These values represent instants 20 minutes apart.

The issue affects:

• Historical dates from regions that previously used local mean time.
• Current timezones with half-hour or quarter-hour offsets.
• Any test or custom Date implementation returning a non-whole-hour offset.

Examples of modern fractional offsets include UTC+05:30, UTC+05:45, UTC+09:30, and UTC-03:30.

Additional Context

We initially encountered this with Europe/Warsaw and 1900-01-01. The JavaScript runtime correctly reports Warsaw's historical offset as UTC+01:24. The incorrect UTC+01:04 value is introduced only during Kendo formatting.

We have implemented a temporary application-level workaround that formats the date portion with Kendo and calculates the timezone offset directly from integer minutes.

StackBlitz

When dateinput format is "d/M/y" and "allowCaretMode" is enabled, users are unable to enter valid dates. Tested with dateinput and datepicker components.

Steps to reproduce

1. Setup a kendo-dateinput component with "allowCaretMode" set to "true" and the "format" set to "d/M/y" (see stackblitz below).
2. Enter a valid single-digit day and valid single-digit month into the input.
3. Try typing a year.
4. Observe that only one character of the year can be entered and the input locks up, preventing the user from completing a valid date.
5. Try typing a double digit month.
6. Observe that only one character of the month can be entered and the input locks up.
7. Try typing a double digit day.
8. Observe that only one character of the day can be entered and the input locks up.

Stackblitz example - angular v22 + kendo v24

https://stackblitz.com/edit/angular-kendo-dateinput-bug-rdocwtvr

Expected Behaviour:

The user should be able to enter a full year, month, and day after typing a valid single-digit day and month.

Observed Behaviour:

After entering a single-digit day and month, the input locks up, preventing the user from typing more than one character for the year or month. This prevents users from entering valid dates, making the input unusable in this scenario.

Thanks

The built-in kendoDropDownFilter directive normalizes text using String.prototype.toLowerCase() when caseSensitive: false. This is locale-insensitive and produces incorrect results for languages with non-standard case-folding rules, most notably Turkish.

The correct fix is to use String.prototype.toLocaleLowerCase(locale), which respects locale-specific case rules. The DropDownFilterSettings interface should expose a locale option for this:

filterSettings = {
  caseSensitive: false,
  operator: 'startsWith',
  locale: 'tr-TR'   // ← proposed new option
};

Affected components: kendoDropDownFilter directive (used with AutoCompleteComponent, ComboBoxComponent, MultiColumnComboBoxComponent, DropDownListComponent, MultiSelectComponent).

Signal Forms are now stable with Angular@22.

It would be nice to have an ability to use all kendo widgets with new form API.

For the Kendo DatePicker, if you try to set the size on a kendo-datepicker with plain text, it will not render and give a console error of "ERROR TypeError: Cannot read properties of undefined (reading 'nativeElement')".

Errors:

// HTML
<kendo-datepicker size="small" ... />

---

But on the other hand, it does work if you create a field of type "DateInputSize" and pass that variable to the size.

// TS
protected size: DateInputSize = 'small';
 

// HTML
<kendo-datepicker [size]="size" ... />

You're docs say

Open the example in a new window to evaluate it with Axe Core or other accessibility tools.  for the Kendo angular grid

When i do that i see the attached error, which is the same issue i get in our product when running playwright axe

That suggests to me that it is not WCAG 2.2 compliant

Ensure elements with an ARIA role that require child roles contain them

.demo-frame.loaded.demo-module--wrap--718a6 > .demo-module--demoWrap--d1437 > .demo-module--explorerWrap--4bf1f.flex-grow-1 > .demo-module--demoBody--97eee > iframe #k-fbe44131-4768-4755-93c3-e321b714780e

<div role="grid" kendodragtargetcontainer="" kendodroptargetcontainer="" mode="manual" class="k-grid-aria-root" id="k-fbe44131-4768-4755-93c3-e321b714780e" aria-label="Data table" aria-rowcount="62" aria-colcount="5">

<div tabindex="-1" class="k-grid-content k-virtual-content">
 
 

   I have tested kendo grid accessibility with AXE Dev tool. Found following errors that seems difficult to fix.

1)Certain ARIA roles must contain particular children

2)Scrollable region must have keyboard access

Any suggestion to fix these above-mentioned issues could be very helpful. Noticed these issues even exist in kendo grid demos published in kendo documentation. Check the link below

stack blitz link : https://stackblitz.com/edit/angular-uhjyd3x9?file=src%2Findex.html

When a tooltip of a dialog is shown and the dialog is closed, the tooltip is still present and is moved into the top left corner.

We use e.g. `kendo-dialog-titlebar` and the close button has a tooltip.

Hi,

if I use both the features locked columns and sticky rows, the sticky rows do not stick in the locked columns.

For me it would be logical if they would stick there too (now the UI looks inconsistent):

Reproduction (forked from your example): https://stackblitz.com/edit/angular-wak7v99i 

Can you please take a look at it?

Best regards,
Michael

Hi,

if I change the [placeholder] input on a kendo-editor, the changes are not reflected.

Reproduction (forked from your example): https://stackblitz.com/edit/angular-uqbchubd

Can you please take a look at it?

Best regards,
Michael

The DrawerAnimation interface isn't exposed in the index file.

DrawerItem, DrawerMode, and DrawerPosition are all exported but DrawerAnimation is missing.

In firefox, open the Kendo Radio Button documentation and slowly resize the window (https://www.telerik.com/kendo-angular-ui/components/inputs/radiobutton)

The radio button will kind of jiggle around and occasionally the white dot in the radio button will become off-center.

This also seems to happen in response to some material bouncy (cubic-bezier) animation transitions.

The directive `kendoGridColumnChooserTool` does not work correctly when having columns which are grouped. See this example: https://stackblitz.com/edit/angular-r9duqpcn?file=src%2Fapp%2Fapp.component.ts

1. It shows that 0 items are selected ("0 Selected items") - This is incorrect because all columns are selected by default. In the example above, I would expect it shows that 4 items are selected.
2. When unselecting an item in the list (popup), it does not actually hide any column.
3. When using directive `kendoGridToolbarTemplate` with `kendo-grid-column-chooser` component, it works as expected. I would expect that `kendoGridColumnChooserTool` directive would work (behave) exactly the same way.

import { Component } from '@angular/core';
import { FormsModule } from '@angular/forms';
import {
  KENDO_GRID,
  KENDO_GRID_EXCEL_EXPORT,
  KENDO_GRID_PDF_EXPORT,
} from '@progress/kendo-angular-grid';
import { KENDO_TOOLBAR } from '@progress/kendo-angular-toolbar';
import { KENDO_LABELS } from '@progress/kendo-angular-label';
import { KENDO_INPUTS } from '@progress/kendo-angular-inputs';
import { KENDO_BUTTONS } from '@progress/kendo-angular-buttons';
import { Product } from './model';
import { products } from './products';

@Component({
  selector: 'my-app',
  standalone: true,
  imports: [
    FormsModule,
    KENDO_GRID_EXCEL_EXPORT,
    KENDO_GRID_PDF_EXPORT,
    KENDO_GRID,
    KENDO_BUTTONS,
    KENDO_TOOLBAR,
    KENDO_LABELS,
    KENDO_INPUTS,
  ],
  template: `
    <kendo-grid
      [kendoGridBinding]="products"
      [pageSize]="5"
      [pageable]="true"
      [sortable]="{ mode: 'multiple' }"
      [style.width.%]="gridWidth"
    >
      <ng-template kendoGridToolbarTemplate position="bottom">
        <kendo-grid-column-chooser></kendo-grid-column-chooser>
      </ng-template>

      <kendo-toolbar overflow="scroll">
        <kendo-toolbar-button kendoGridColumnChooserTool></kendo-toolbar-button>
      </kendo-toolbar>

      <kendo-grid-column-group title="TestA">
      <kendo-grid-column
        field="ProductName"
        title="Product Name"
      ></kendo-grid-column>
      </kendo-grid-column-group>

      <kendo-grid-column-group title="TestB">
      <kendo-grid-column
        field="UnitPrice"
        filter="numeric"
        title="Price"
      ></kendo-grid-column>
      <kendo-grid-column
        field="Discontinued"
        filter="boolean"
        title="Discontinued"
      ></kendo-grid-column>
      <kendo-grid-column
        field="UnitsInStock"
        filter="numeric"
        title="Units In Stock"
      ></kendo-grid-column>
      </kendo-grid-column-group>
    </kendo-grid>
  `,
  styles: [
    `
      .example-info {
        background: rgba(83, 146, 228, 0.1);
        border-radius: 2px;
        margin: 10px auto 10px auto;
        padding: 15px;
        border-left: 4px solid #5392e4;
        font-size: 14px;
      }
    `,
  ],
})
export class AppComponent {
  public gridWidth: number = 100;
  public products: Product[] = products;
}

Hello Support,

There is a feature request for this, but I see this as a bug. The Agenda view in the scheduler is advertised to work perfectly on mobile, but I would expect to see the event column one way or another. Now you can only see timeslots, which is not that useful. Can you fix it by making the event column available, maybe as part of the time as text or some other solution.

Ran this on StackBlitz 

import { Component } from '@angular/core';
import {
  LegendLabelsContentArgs,
  SeriesClickEvent,
} from '@progress/kendo-angular-charts';
import { IntlService } from '@progress/kendo-angular-intl';

@Component({
  selector: 'my-app',
  template: `
    <kendo-chart
      (plotAreaClick)="onClick($event)"
      [transitions]="false"
      title="World Population by Broad Age Groups"
    >
      <kendo-chart-legend position="bottom"></kendo-chart-legend>
      <kendo-chart-series>
        <kendo-chart-series-item
          type="donut"
          [data]="pieData"
          field="value"
          categoryField="category"
          explodeField="exploded"
          [labels]="{ visible: true, content: labelContent }"
        >
        </kendo-chart-series-item>
      </kendo-chart-series>
    </kendo-chart>
  `,
})
export class AppComponent {
  public pieData: Array<{
    category: string;
    value: number;
    exploded: boolean;
  }> = [
    { category: '0-14', value: 0.2545, exploded: false },
    { category: '15-24', value: 0.1552, exploded: false },
    { category: '25-54', value: 0.4059, exploded: false },
    { category: '55-64', value: 0.0911, exploded: false },
    { category: '65+', value: 0.0933, exploded: false },
  ];

  constructor(private intl: IntlService) {
    this.labelContent = this.labelContent.bind(this);
  }

  public labelContent(args: LegendLabelsContentArgs): string {
    return `${args.dataItem.category} years old: ${this.intl.formatNumber(
      args.dataItem.value,
      'p2'
    )}`;
  }

  public onClick(event: any): void {
    console.log('Click');
  }
}

When the event is seriesClick, it works as expected, and if I change the type to bar, it works as expected, but when it's as shown as above, the onClick event isn't triggered. 

As I have donuts/pies that might not have data in it, I needed to use plotAreaClick (which I have done for the bar charts)

Thanks,

Add support for Angular's Trusted Types to eliminate CSP compatibility issues and errors when using the Kendo UI for Angular components in applications with strict Trusted Types security policies.

At the moment, the internal logic of the Kendo UI for Angular components uses innerHTML in various scenarios, like placeholder content for virtualization, dynamic rendering of icons and indicators, etc.

Thus, when applications have strict CSP with Trusted Types enabled, developers encounter a "This document requires 'TrustedHTML' assignment" error. 

Although all content set via innerHTML is internally controlled and secure, the Kendo UI for Angular components should work seamlessly in applications with strict CSP and Trusted Types policies without requiring developers to modify their security configuration.