label <-
selection: char_array|imageCurrently displayed text or image
object. If the selection is a text (instance of class char_array),
it is displayed in label<-font.
If it is a markup
object, the markup is rendered, mixing fonts, styles and (theme)
colours. The label<-font
is used for text without a font in the markup. If the label is not
active, the colours of the text in the markup are ignored. The field
width is described by label<-length.
If the actual text does not fit in the field the label is automatically
enlarged.
