wpf: how to show tooltip when button disabled by command?
ToolTipService.ShowOnDisabled="True"
This is a good method to add to your startup code:
ToolTipService.ShowOnDisabledProperty.OverrideMetadata(
typeof(FrameworkElement),
new FrameworkPropertyMetadata(true));
It ensures that for any class inheriting from FrameworkElement, tooltips are shown even if a control instance is disabled. This covers all elements that can have a tooltip.