Mastering InForm: Click Timings

[Qwerkey]

I have a project where I have the __UI_BeforeUpdateDisplay loop, the __UI_Click loop and a Calculations loop (in its own subroutine).

Inside the __UI_BeforeUpdateDisplay loop, there is a Condition A which may become True, and if so it sets a Flag to inform the  Calculations loop.

There is a Button which when clicked will reset the Flag and will alter things in the __UI_BeforeUpdateDisplay loop so that  Condition A will be False.

If I were not doing this in InForm, my Mouse Polling would be at the start of the equivalent of the __UI_BeforeUpdateDisplay loop so that timings always ensure the Flag is reset at the correct moment and that the Condition A is False.

However, suppose in the Inform situation, the Mouse is clicked part way through the __UI_BeforeUpdateDisplay loop.  The Flag would be reset, but at the end of that __UI_BeforeUpdateDisplay loop cycle the Condition A has still been True and therefore sets the Flag again.

I hope that you've get all that!  How does InForm Mouse Polling ensure that Click events do not occur 'part way through' the __UI_BeforeUpdateDisplay loop?  I suspect that this is another of my dumb questions.  In the actual program, the Reset Click always works properly.

Richard

[FellippeHeitor]

How does InForm Mouse Polling ensure that Click events do not occur 'part way through' the __UI_BeforeUpdateDisplay loop?

Input processing is done by a TIMER while drawing (which triggers __UI_BeforeUpdateDisplay) is done by another TIMER. A TIMER procedure won't execute over itself.

[FellippeHeitor]

Just as proof of concept, try the code below. It'll run SUB halfSecond every 500ms (times between runs shown vary slighlty). Whenever you feel like it, hold down shift. That'll enter a LOOP in the halfSecond sub that'll be run for as long as the key is held down. No other instance of the SUB will be run while the counter is going up and next time the SUB is run you'll see the time elapsed since you let go of shift:

Code: QB64: [Select]

1. t1 = _FREETIMER
2. ON TIMER(t1, .5) halfSecond
3. TIMER(t1) ON
4.  
5. DO
6.     _LIMIT 1 'do nothing; only timed sub will run
7. LOOP
8.  
9. SUB halfSecond
10.     DIM counter AS _UNSIGNED LONG
11.     STATIC i, lastRun#
12.     IF lastRun# > 0 THEN
13.         PRINT "time since last run: "; INT((TIMER - lastRun#) * 1000); "ms",
14.     END IF
15.     lastRun# = TIMER
16.  
17.     IF _KEYDOWN(100304) OR _KEYDOWN(100303) THEN
18.         i = i + 1
19.         PRINT
20.         PRINT "Instance of timer: "; i; " - shift pressed..."
21.         row = CSRLIN
22.         col = POS(1)
23.         DO WHILE _KEYDOWN(100304) OR _KEYDOWN(100303)
24.             counter = counter + 1
25.             LOCATE row, col
26.             PRINT counter;
27.             _LIMIT 30
28.         LOOP
29.         i = i - 1
30.     END IF
31. END SUB
32.