How to threading data in app?

[tanthinh1510]

- you have a number of rectangles.
Cheers,
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Number of rectangles is random. I can enter any number

- they can change position
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yes, they can change position

- their color depends on that position
Cheers,
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Yes, their color depends on that position

- you want to update color for all rectangles every 30 seconds, not on every posiiton change
Cheers,
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Yes. because color screen always change, so I want to update color for all rectangles every 30 miliseconds(not 30 senconds)
I think cause is all rectangle call function at the same time. But I have not found a way to solve.