BackgroundColor is not applied when the View is focused on UWP

Question

This seems to be behavior in Entry also. But we can change this behavior in Entry using Effects (https://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/effects/). We have tried CustomView but the entire behavior is changed In Xamarin.Forms UWP does not update the background color in focused state. In this, I have created “NumericTextBox” which is inherit from TextBox in UWP. And I have created a “NumericTextBox_Forms” inherits from View in XForms. In UWP Renderer class create a new instance for “NumericTextBox” and set native control. And please find my sample below.

<StackLayout Padding="0,20,0,0">
        <Entry Keyboard="Numeric">
            <Entry.Effects>
                <local:FocusEffect/>
            </Entry.Effects>
            <Entry.Triggers>
                <Trigger TargetType="Entry" Property="IsFocused" Value="True">
                    <Setter Property="BackgroundColor" Value="Yellow" />
                </Trigger>
            </Entry.Triggers>
        </Entry>
        <NumericTextBox_Forms>
            <NumericTextBox_Forms.Effects>
                <local:FocusEffect/>
            </NumericTextBox_Forms.Effects>
            <NumericTextBox_Forms.Triggers>
                <Trigger TargetType="sync:SfMaskedEdit" Property="IsFocused" Value="True">
                    <Setter Property="BackgroundColor" Value="Blue" />
                </Trigger>
            </NumericTextBox_Forms.Triggers>
        </NumericTextBox_Forms >

    </StackLayout>

CoCaIceDew CoCaIceDew · Accepted Answer · 2020-05-22T04:44:30

BackgroundColor is not applied when the View is focused on UWP

For the testing SfMaskedEdit contains method internal override IsFocused trigger. For the scenario, I suggest make custom render for NumericTextBox_Forms then edit the bg color in control GettingFocus event.

[assembly: ExportRenderer(typeof(NumericTextBox_Forms), typeof(NumericTextBoxRender))]
namespace XamarinEffect.UWP
{
    public class NumericTextBoxRender :SfMaskedEditRenderer
    {
        protected override void OnElementChanged(ElementChangedEventArgs<Syncfusion.XForms.MaskedEdit.SfMaskedEdit> e)
        {
            base.OnElementChanged(e);

            if(Control != null)
            {
                Control.GettingFocus += Control_GettingFocus;
            }
        }

        private void Control_GettingFocus(Windows.UI.Xaml.UIElement sender, Windows.UI.Xaml.Input.GettingFocusEventArgs args)
        {
            Control.Background = new SolidColorBrush(Colors.Blue);
        }
    }
}

I tried above, it works well in my side, hope could solve your problem.

BackgroundColor is not applied when the View is focused on UWP

1 Answers