DropDown popup overflows the top of the viewport - items wrapper max-height ignores the filter container height

Radzen.Blazor Components
1

Environment

- Radzen.Blazor 12.1.5

- .NET 10, Blazor Server (interactive server render mode)

- RadzenDropDown with AllowFiltering="true", FilterAsYouType="true", Multiple="true" (also single-select)

- The dropdown is rendered inside a side dialog (DialogService.OpenSideAsync)

What happens

On a small viewport the dropdown has more room above the trigger than below, so the list opens upwards with the default max-height: 200px on .rz-dropdown-items-wrapper. After a visual viewport resize event fires, the popup becomes much taller (max-height changes to 496.6px) and its top edge, including the filter input, moves above the top of the screen.

Setting a fixed height as suggested in Change Dropdown number of drop items - Radzen.Blazor Components - Radzen seems to do the job, but is not ideal for varying screen sizes.

Any suggestions? Thank you in advance.

2

We will do our best to improve it in our next update before the end of the week.

1 Like