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Window Position

The Window offers several ways to control its position:

The Window renders in the root of the application or in its containment element. If the app is using special CSS positioning, margins, or other offsets on the Window ancestors, these CSS styles may affect the position of the Window.


The Centered parameter determines if the Window displays centered in the viewport. The parameter value is true by default.

A centered Window applies the following CSS styles, which maintain the centered position even if the viewport size changes:

.k-centered {
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);

If the Top or Left parameters are set and not empty, they take precedence over Centered. To center the Window dynamically through its Centered parameter, bind the Top and Left parameters too, so you can reset them to string.Empty or null.

Center the Window

<TelerikWindow Centered="true" Visible="true">
        Window Title
        A Centered Window


By default, users can drag and resize the Window without constraints. You can restrict the Window's visual position to the boundaries of a specific container:

  1. Define a non-modal Window component inside the desired container.
  2. Set the Window ContainmentSelector parameter to a unique CSS selector, which points to the container.
  3. Apply a position:relative style to the container.

In this case, the Window will render inside the specified container and not as a child of the TelerikRootComponent.

Using ContainmentSelector to limit Window dragging and resizing

<div id="window-container"
     style="position: relative; border: 1px solid red; margin: 20vh; height: 50vh; width: 50vw;">

    <TelerikButton OnClick="@( () => WindowVisible = !WindowVisible )">Toggle Window</TelerikButton>

    <TelerikWindow ContainmentSelector="#window-container"
            <WindowAction Name="Maximize" />
            <WindowAction Name="Close" />
        <WindowTitle>Contained Window</WindowTitle>
            This Window can be dragged, resized, and maximized within the boundaries of the red box.


@code {
    private bool WindowVisible { get; set; } = true;

    private string WindowWidth { get; set; } = "300px";

Top and Left

The Top and Left parameters control the Window placement on the page. The resulting position depends on the whole page content and not on the viewport or the current scroll offset.

When the Window ContainmentSelector parameter is set, the Top and Left parameters apply with regard to the top-left corner of the containment element.

Using Top and Left to manage the Window position

    <code>WindowLeft</code>: @WindowLeft
    <br />
    <code>WindowTop</code>: @WindowTop

<TelerikWindow @bind-Left="@WindowLeft"
        The values of <code>WindowLeft</code> and <code>WindowTop</code> change after the user ends dragging or resizing.

@code {
    private string WindowLeft { get; set; } = "50px";

    private string WindowTop { get; set; } = "50px";

See Also

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