Accessible Terminal

[Marc Mulcahy <marc mulcahy sun com>]

Hi all,

An initial stab at the libzvt accessibility support is done with the 
following rather important issues outstanding:

1. There is no role for the Accessible terminal.  How about adding 
ATK_ROLE_TERMINAL to ATK?

2. There is no efficient way to implement getRunAttributes in the 
terminal.  Unless there are objections, I'll just implement runs of one 
character a piece as per Java accessibility.

3. The ZvtTerm widget doesn't emit a signal when the selection 
changes.  Should it, and if so, I assume the signal handler in 
ZvtAccessible would emit the "selection" property change.

4. The ZvtTerm widget emits a signal for text added, but as far as I can 
tell, the signal doesn't contain information about where the text was 
written to the screen.  Is it acceptable to emit a "text changed" signal 
and leave it up to the AT to figure out the details of the change?

5. Screen readers which read text from terminals often need to do the 
following task which isn't very well suppported, if at all, by AtkText:
	a. New text is received and prepared to be written to the screen.
	b. The screen reader examines the proposed location of the new text, and 
grabs the text
		currently in that location on the screen.
	c. If the text is the same but the attributes show it is switching from 
highlighted to normal,
		nothing is spoken.
	d. Otherwise, the text is spoken.

How can we do this with AtkText?