Note
The Dialog component already contains a focus trap, it is not necessary to add one yourself.
Usage
By default, when the component is created or enabled, focus is set on the first tabbable child element. This behavior can be modified by using the DefaultFocus property.
If still enabled, the focus is restored to the original element when the component is disposed.
Take note that the focus trap is only for TAB key management; it does not prevent setting the focus elsewhere with the mouse, so you may use an Overlay to prevent this.
<div class="d-flex mb-4"> <MudCheckBox @bind-Value="Disabled" Label="Disabled"></MudCheckBox> <MudSelect @bind-Value="DefaultFocus" Label="Default Focus" Dense="true" Class="ml-4"> <MudSelectItem Value="DefaultFocus.None">None</MudSelectItem> <MudSelectItem Value="DefaultFocus.Element">Element</MudSelectItem> <MudSelectItem Value="DefaultFocus.FirstChild">FirstChild</MudSelectItem> <MudSelectItem Value="DefaultFocus.LastChild">LastChild</MudSelectItem> </MudSelect> </div> <MudTextField T="string" Variant="Variant.Outlined"></MudTextField> <MudPaper Class="pa-4"> <MudFocusTrap Disabled="Disabled" DefaultFocus="DefaultFocus"> <MudTextField T="string" Variant="Variant.Outlined"></MudTextField> <MudTextField T="string" Variant="Variant.Outlined"></MudTextField> <MudTextField T="string" Variant="Variant.Outlined"></MudTextField> </MudFocusTrap> </MudPaper> <MudTextField T="string" Variant="Variant.Outlined"></MudTextField>
@code { bool Disabled { get; set; } DefaultFocus DefaultFocus { get; set; } = DefaultFocus.FirstChild; }