set_subtitle

Description:

public void set_subtitle (string? subtitle)

Sets the subtitle of the header bar.

The title should give a user an additional detail to help them identify the current view.

Note that [class@HeaderBar] by default reserves room for the subtitle, even if none is currently set. If this is not desired, set the [ property@HeaderBar:has-subtitle] property to `FALSE`.

Parameters:

this	a header bar
subtitle	a subtitle