How to manage keyboard interactions with text field in Blazor ListBox?

Overview

When integrating text fields such as SfTextBox or SfNumericBox within a SfListBox component, it is essential to manage keyboard interactions properly to ensure a seamless user experience. A common issue arises when the first key press is not recognized due to the default action of the SfListBox not being cancelled. This article provides a solution to prevent the default list box event when editing text fields and re-enable it once editing is complete.

Solution

To resolve the issue of the first key press not being recognized in text fields within a SfListBox, we can utilize the focusin and focusout events of the SfTextBox and SfNumericBox. By handling these events, we can control when to prevent the default action of the SfListBox.

Here is a code snippet demonstrating how to implement this solution:

<SfListBox @ref="listObj" TValue="string[]" DataSource="@Data" TItem="ListData">
    <ListBoxFieldSettings Text="Text"></ListBoxFieldSettings>
    <ListBoxTemplates TItem="ListData">
        <ItemTemplate>
            <SfTextBox Placeholder=@((context as ListData).Text) @onfocusin="@keyPress" @onfocusout="@onBlur"></SfTextBox>
        </ItemTemplate>
    </ListBoxTemplates>
    <ListBoxEvents TValue="string[]" TItem="ListData" OnActionBegin="OnActionBegin" ListBoxItemKeyDown="ListBoxItemKeyDown"></ListBoxEvents>
</SfListBox>

@code {
    public void OnActionBegin(Syncfusion.Blazor.DropDowns.ActionBeginEventArgs args)
    {
        args.Cancel = isEditing;
    }
    private void keyPress()
    {
        isEditing = true;
    }
    private void onBlur()
    {
        isEditing = false;
    }
    private void ListBoxItemKeyDown(ListBoxKeyDownEventArgs args)
    {
        args.PreventDefaultAction = !isEditing;
    }
}

In the above code:

• OnActionBegin event is used to cancel all events of the SfListBox when editing is in progress.
• keyPress event sets a flag isEditing to true when the text field gains focus.
• onBlur event resets the isEditing flag to false when the text field loses focus.
• ListBoxItemKeyDown event is used to prevent the default action of the SfListBox only when isEditing is false.

By implementing the above code, the SfListBox will allow keyboard typing in the text fields without interfering with the first key press.

Demo

To see this solution in action, visit the following demo link: Syncfusion Blazor Playground

References

• Syncfusion ListBox Documentation
• Syncfusion TextBox Documentation
• Syncfusion NumericBox Documentation

Please note that the provided code snippet and demo link are based on the Syncfusion Blazor components and may require adjustments if used with other frameworks or versions.

Conclusion:

I hope you enjoyed learning about how to manage keyboard interactions with text field in Blazor ListBox.

You can refer to our Blazor ListBox feature tour page to know about its other groundbreaking feature representations and documentation, and how to quickly get started for configuration specifications.

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