_SCREENEXISTS
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The _SCREENEXISTS function returns true (-1) once a screen has been created.
Syntax
- screenReady%% = _SCREENEXISTS
Description
- Function returns true (-1) once a program screen is available to use or change.
- Can be used to avoid program errors because a screen was not ready for input or alterations.
- Use before _TITLE, _SCREENMOVE and other functions that require the output window to have been created.
Examples
- Example
- Waiting in a loop until the screen exists to add the title. The _LIMIT prevents the loop from using all CPU time while waiting.
SCREEN 12 DO: _LIMIT 10: LOOP UNTIL _SCREENEXISTS _TITLE "My Title" |
See also