ngraham added a comment.
How about changing the outline or background of the text box to the Positive or Negative color from the active color theme? That way (for people with sensible color themes), the text box would show red if the value is invalid. I believe GNOME does something similar to this for their IP address validator, and in my experience it works quite nicely. REPOSITORY R116 Plasma Network Management Applet REVISION DETAIL https://phabricator.kde.org/D15093 To: andersonbruce, #plasma, jgrulich, pino Cc: acrouthamel, K900, pino, lbeltrame, ngraham, plasma-devel, ragreen, Pitel, ZrenBot, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas, apol, mart
