This function retrieves a button click event from the event queue, which is triggered when the user presses and then releases a button.
This function must be called to clear event 1 from guiWaitEvent.
Input:
None.
Output:
button : SYSHANDLE
The handle to the button.
long_press : BOOL
True if the button was kept pressed for a while, false if it was released sooner.
Returns: INT
0
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- Data is ready.
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-1
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- Interface is not open (see guiOpen).
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-6
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- Data is not ready
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-11
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- The GUI API is not supported.
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Declaration:
FUNCTION guiButtonClickEvent : INT;
VAR_INPUT
button : ACCESS SYSHANDLE;
long_press : ACCESS BOOL;
END_VAR;
Example:
...
FUNCTION ButtonHandler
VAR
rc : INT;
handle : SYSHANDLE;
tag : DINT := 0;
lp : BOOL;
END_VAR;
rc := guiButtonClickEvent(button := handle, long_press := lp);
IF rc = 0 THEN
guiGetTag(handle := handle, tag := tag);
IF lp THEN
DebugFmt(message:="Button with tag \4 was pressed", v4 := tag);
ELSE
DebugFmt(message:="Button with tag \4 was clicked", v4 := tag);
END_IF;
END_IF;
END_FUNCTION;
...
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