See gtksource.print_compositor.PrintCompositor.setHeaderFormat for more information about the parameters.
true if you want a separator line to be printed.
a format string to print on the left of the footer.
a format string to print on the center of the footer.
a format string to print on the right of the footer.
See gtksource.print_compositor.PrintCompositor.setHeaderFormat for more information about the parameters.