mirror of
https://github.com/QB64Official/qb64.git
synced 2024-07-01 09:10:37 +00:00
32 lines
823 B
Plaintext
32 lines
823 B
Plaintext
{{DISPLAYTITLE:_SCREENEXISTS}}
|
|
The [[_SCREENEXISTS]] function returns true (-1) once a screen has been created.
|
|
|
|
|
|
{{PageSyntax}}
|
|
: {{Parameter|screenReady%%}} = [[_SCREENEXISTS]]
|
|
|
|
|
|
{{PageDescription}}
|
|
* 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.
|
|
|
|
|
|
{{PageExamples}}
|
|
''Example:'' The loop busy-waits until the screen exists to add the title.
|
|
{{CodeStart}} '' ''
|
|
{{Cl|SCREEN}} 12
|
|
{{Cl|DO}}: {{Cl|LOOP}} {{Cl|UNTIL}} _{{Cl|SCREENEXISTS}}
|
|
{{Cl|_TITLE}} "My Title"
|
|
{{CodeEnd}}
|
|
|
|
|
|
{{PageSeeAlso}}
|
|
* [[_FULLSCREEN]]
|
|
* [[_SCREENIMAGE]]
|
|
* [[$CONSOLE]]
|
|
* [[$RESIZE]]
|
|
|
|
|
|
{{PageNavigation}}
|