C# UWP - Keep Button Border Visible During Mouse Over

Question

I have a page with several buttons that all follow this template:

<Button
    Grid.Row="0"
    Grid.Column="0"
    Width="50"
    Height="100"
    BorderBrush="Silver"
    BorderThickness="1">
    <TextBlock
        FontSize="12"
        Foreground="Black">UN</TextBlock>
</Button>

The border is visible so long as the mouse is not over the button. It disappears as soon as the mouse hovers over it.

How can I keep the border visible at all times?

Answer 1

Update:

As @Raymond Chen mentioned, an easier way is to put the Button inside a Border so that the Button will be a child of the Border. So you don't need to set the BorderBrush and BorderThickness of the Button. Also, you don't need to change the style.

Old reply:

The reason for this behavior is that when your pointer moves over the button, it triggers the PointerOver state of the button which will change the BorderBrush and the border will change.

To change this behavior, what you need is to find out the style of the button and disable the BorderBrush change in VisualStates like PointerOver or Pressed, etc.

Here are the steps that you could follow:

1. You need to get button style first. There are two ways to do it.

   A. Get the default style of Button control from generic.xaml file and apply the style to your Button control.

   B. open the Document Outline Window in your VS and find the target button control. Right-click on the button, go to Edit Template -> Edit a copy. Then the VS will create a default style of the button automatically.

2. Find the PointerOver, Pressed, Disabled VisualStates in the added style, and remove the ObjectAnimationUsingKeyFrames that targets the BorderBrush.

The code looks like this:

        <Style x:Key="ButtonStyle1" TargetType="Button">
        <Setter Property="Background" Value="{ThemeResource ButtonBackground}"/>
        <Setter Property="BackgroundSizing" Value="OuterBorderEdge"/>
        <Setter Property="Foreground" Value="{ThemeResource ButtonForeground}"/>
        <Setter Property="BorderBrush" Value="{ThemeResource ButtonBorderBrush}"/>
        <Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}"/>
        <Setter Property="Padding" Value="{StaticResource ButtonPadding}"/>
        <Setter Property="HorizontalAlignment" Value="Left"/>
        <Setter Property="VerticalAlignment" Value="Center"/>
        <Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}"/>
        <Setter Property="FontWeight" Value="Normal"/>
        <Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}"/>
        <Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}"/>
        <Setter Property="FocusVisualMargin" Value="-3"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="Button">
                    <ContentPresenter x:Name="ContentPresenter" AutomationProperties.AccessibilityView="Raw" Background="{TemplateBinding Background}" BackgroundSizing="{TemplateBinding BackgroundSizing}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" ContentTemplate="{TemplateBinding ContentTemplate}" CornerRadius="{TemplateBinding CornerRadius}" Content="{TemplateBinding Content}" ContentTransitions="{TemplateBinding ContentTransitions}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}">
                        <VisualStateManager.VisualStateGroups>
                            <VisualStateGroup x:Name="CommonStates">
                                <VisualState x:Name="Normal">
                                    <Storyboard>
                                        <PointerUpThemeAnimation Storyboard.TargetName="ContentPresenter"/>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="PointerOver">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPointerOver}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <!--<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPointerOver}"/>
                                        </ObjectAnimationUsingKeyFrames>-->
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPointerOver}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <PointerUpThemeAnimation Storyboard.TargetName="ContentPresenter"/>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Pressed">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPressed}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <!--<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPressed}"/>
                                        </ObjectAnimationUsingKeyFrames>-->
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPressed}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <PointerDownThemeAnimation Storyboard.TargetName="ContentPresenter"/>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Disabled">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundDisabled}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <!--<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushDisabled}"/>
                                        </ObjectAnimationUsingKeyFrames>-->
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundDisabled}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                            </VisualStateGroup>
                        </VisualStateManager.VisualStateGroups>
                    </ContentPresenter>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

And make sure your button applies this style

  <Button Style="{StaticResource ButtonStyle1}"

Now you could make the border always available on your Button.