#860 – Making a Tooltip Partially Transparent

You’ll normally want your tooltips fully opaque so that the user can easily read the content on the tooltip.  However, there might be cases when you’d like the tooltip at least partially transparent, to hint at content behind the tooltip.

To make a tooltip partially transparent, you can set its Background property to a color that includes an alpha value indicating transparency.

The alpha component of a color value ranges from 0-255 (00-FF), with a value of 0 representing a fully transparent color and 255 representing a fully opaque color.

In the example below, we set the alpha portion of the color value to D5, which is slightly transparent.

        <Button Content="Read a Book"
                Padding="10,5" HorizontalAlignment="Center">
            <Button.ToolTip>
                <ToolTip Background="#D5F0F0FF">
                    <StackPanel>
                        <TextBlock Text="Reading Suggestion" FontWeight="Bold"/>
                        <TextBlock Text="Charles Dickens" Margin="5"/>
                    </StackPanel>
                </ToolTip>
            </Button.ToolTip>
        </Button>

When the tooltip appears, you can see through it to the button behind it.