select_region
Description:
Selects a range of characters in the label, if the label is selectable.
See set_selectable. If the label is not selectable, this function has no
effect. If start_offset or end_offset are -1, then the end of the label will be substituted.
Parameters:
| this |
a Label |
| start_offset |
start offset (in characters not bytes) |
| end_offset |
end offset (in characters not bytes) |