Texas Instruments TI-89 Tip List page 350

enddlog
elseif key=270 then
dialog
title "Help"
text "F3"
enddlog
endif
endloop
if dim(m)≠0:expr(m)
disphome
EndPrgm
The basic principles are:
1. Display the graph screen. You may need to clear the axes and make other settings, depending
on your program.
2. Display a custom toolbar with only Title entries, no Item entries.
3. Execute a loop which includes a getkey() call get key press codes, and test the key code for
function keys. The loops traps the function key presses.
When tooltab() is executed and [F2] is pressed, this screen is shown:
The dialog boxes are only examples; your program would instead perform the code needed to perform
the desired function.
Another feature of tooltab() is restoring a custom menu. tooltab() replaces any custom menu with its
own, so it would be considerate to restore the user's custom menu. No TI Basic program which
changes the screen from Home to some other can restore a custom menu, but we can at least make it
convenient to do by pressing [CUSTOM] after the program ends. tooltab() accomplishes this by
accepting a program name as a string argument m, then executing
if dim(m)≠0:expr(m)
before exiting. For example, suppose I have a program to set up a custom menu called
main\custom92(), then I would use this call:
tooltab("main\custom92()")
© [F3] key
© Restore menu
© Display home screen
© Restore menu
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