Android Code Snippet [B4X] Wait for multiple tasks to complete

emexes said:

It's probably one of those machine code instructions that overlaps with the instructions before and after it, and thus takes no additional cycles to execute.

Light travels 0.3 nanometers in that specified time, which is about the diameter of one silicon atom, which would represent the gap between the two instructions.

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kimstudio said:

It is crucial to understand the difference between pass by value and pass by reference for sub parameters.

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LucaMs said:

Exactly?

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Erel said:

A pattern such as this one can be used when you want to run multiple resumable subs concurrently and wait for all of them to complete before continuing:

B4X:

    Dim status(1) As Int
    Test1(status)
    Test2(status)
    Test3(status)
    Do While status(0) < 3
        Sleep(50)
    Loop
    Log("all tasks completed. Continue with your next task...")

Private Sub Test1 (Status() As Int)
    Sleep(Rnd(1, 1000))
    Log("Test1 completed")
    Status(0) = Status(0) + 1
End Sub

Private Sub Test2 (Status() As Int)
    Sleep(Rnd(1, 1000))
    Log("Test2 completed")
    Status(0) = Status(0) + 1
End Sub

Private Sub Test3 (Status() As Int)
    Sleep(Rnd(1, 1000))
    Log("Test3 completed")
    Status(0) = Status(0) + 1
End Sub

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Dim NumStillRunning(1) As Int
TestX(NumStillRunning)
TestY(NumStillRunning)
TestZ(NumStillRunning)
Do While NumStillRunning(0) > 0
    Sleep(50)
Loop
Log("all tasks completed. Continue with your next task...")

Private Sub TestX (NumStillRunning() As Int)
    NumStillRunning(0) = NumStillRunning(0) + 1
    Sleep(Rnd(1, 1000))
    Log("TestX completed")
    NumStillRunning(0) = NumStillRunning(0) - 1
End Sub

Private Sub TestY (NumStillRunning() As Int)
    NumStillRunning(0) = NumStillRunning(0) + 1
    Sleep(Rnd(1, 1000))
    Log("TestY completed")
    NumStillRunning(0) = NumStillRunning(0) - 1
End Sub

Private Sub TestZ (NumStillRunning() As Int)
    NumStillRunning(0) = NumStillRunning(0) + 1
    Sleep(Rnd(1, 1000))
    Log("TestZ completed")
    NumStillRunning(0) = NumStillRunning(0) - 1
End Sub