systemFontsDidChange method Null safety
mustCallSuper">@mustCallSuperprotected">@protected
A callback that is called when system fonts have changed.
By default, markNeedsLayout is called on the RenderObject implementing this mixin.
Subclass should override this method to clear any extra cache that depend on font-related metrics.
Implementation
@protected
@mustCallSuper
void systemFontsDidChange() {
markNeedsLayout();
}