Gets the location of a specified offset in the current composed text,
or of the selection in committed text.
This information is, for example, used to position the candidate window
near the composed text, or a composition window near the location
where committed text will be inserted.
If the component has composed text (because the most recent
InputMethodEvent sent to it contained composed text), then the offset is
relative to the composed text - offset 0 indicates the first character
in the composed text. The location returned should be for this character.
If the component doesn't have composed text, the offset should be ignored,
and the location returned should reflect the beginning (in line
direction) of the highlight in the last line containing selected text.
For example, for horizontal left-to-right text (such as English), the
location to the left of the left-most character on the last line
containing selected text is returned. For vertical top-to-bottom text,
with lines proceding from right to left, the location to the top of the
left-most line containing selected text is returned.
The location is represented as a 0-thickness caret, that is, it has 0
width if the text is drawn horizontally, and 0 height if the text is
drawn vertically. Other text orientations need to be mapped to
horizontal or vertical orientation. The rectangle uses absolute screen
coordinates.
Returns:
a rectangle representing the screen location of the offset
Parameters:
- offset - the offset within the composed text, if there is composed
text; null otherwise