Looping problem...

[rjlohan]

I am trying to make a form flash colours whilst some other activity takes place, and then stop. I use the following functions to flash the form.

Private Function RunWalkthrough_0_1()
    'Explain the display
    Call FlashForm(frmControlHead)
   'Do stuff.... lalala
    Call StopFlashControl
End Function
 
Public Sub FlashForm(frmForm As Form, Optional ColourFlash = -1)
On Error Resume Next
    'Flash form between two colours every second
    flgFlashControl = True
    
    'Set flash colour and original colour
    Dim OriginalColour As Long, FlashColour As Long
    FlashColour = IIf((ColourFlash < 0), DEFAULT_FLASH_COLOUR, ColourFlash)
    OriginalColour = frmForm.BackColor
    
    'Flash form
    Do While (flgFlashControl)
        DoEvents
        'Swap colours
        If frmForm.BackColor = FlashColour Then
            frmForm.BackColor = OriginalColour
        Else
            frmForm.BackColor = FlashColour
        End If
        'Wait
        PauseMe (50000)
    Loop
    
    'Return form colour
    frmForm.BackColor = OriginalColour
End Sub
 
Public Sub StopFlashControl()
    'Reset flashing flag
    flgFlashControl = False
End Sub
 
 
'Pause system in a loop temporarily
Public Sub PauseMe(lngPauseDuration As Long)
    Dim i As Long
    Do Until i = lngPauseDuration
        i = i + 1
        DoEvents
    Loop
End Sub

But the code never seems to leave the FlashForm function. StopFlashControl is never callled. Bit of help, please?

[tennis_blues]

i could be wrong......but it looks like you never get out of your do while loop in FlashForm....

it looks like flgFlashControl is always true

so it never gets to the end of FlashForm.....hence never getting back to RunWalkthrough_0_1 hence never getting to StopFlashControl

i am new to vb so please ignore post if i am off base! - lol

[VictorB212]

You'll have to use a timer control, and place some of the code in there. With it coded as currently, executing won't continue until the function Flash... returns. What you need is a timer event that sets the flash flag to false at some point... or even better, place the flashing code in a timer with an interval of 2000, then enable the timer where you call the Flash... function, and disable the timer when you want flashing to cease.

[WorkHorse]

flgFlashControl is never changed within your Do Loop, so it will always be True so the loop will just keep going and going...

[rjlohan]

I'm aware that the flag won't change within the loop, but it's a public flag, and I thought by calling another function, it would set it false.

[WorkHorse]

It will. Try

Public flgFlashControl
Private Sub Command1_Click()
    RunWalkthrough_0_1
End Sub
 
Private Sub Command2_Click()
    Call StopFlashControl
End Sub

[rjlohan]

But it's not. That's the problem...

[WorkHorse]

I see. DoEvents lets you "jump" out of the VB code and fire a new event. But I think you want to just have the code run two functions at the same time. Timer control solution would work. Otherwise maybe someone else can provide some type of threading/hooking sort of explanation or solution.

[rjlohan]

Threading would probably solve it, but I gather VB isn't so good at that.

Have got a ****ty workaround for now. Time constraints and all that.

[Bruce Fox]

rjlohan - Gday,

You could place a counter in the loop, and when that value is reaced
Exit Do, Or

Set an external Boolean Flag, that if detected in your loop will
Exit Do.

(Either way you go do without the StopFlashing Sub and handle
the 'Stop' within the Loop 'Counter, or Bololean Flag)

As mentioned, the problem is you will never get to the StopFlashing Sub, cause ur in a loop (as you know).



Bruce.

[rjlohan]

Counter's no good unfortunately, as the end of the loop varies based on the length (in seconds) of an audio file. I'm trying to do some automated walkthrough stuff in a hurry, so I'm just gonna go with my 'hack' solution for now.

Cheers,
RJ

[Beacon]

What are you trying to do rj?

Stop the flashing of the form?

[WorkHorse]

I think he wants the form to flash while VB is running other code. I'd use the Timer control. Thought that's what Timer was for. But I don't know.

[rjlohan]

See, the problem is, that I'm also playing audio, and I want to synchronise a series of events. It's a right pain in the arse, I tell you...

[Beacon]

Ok how's this:

You'll need a command button a timer! Just for testing! Set the timer enabled to false to start with and it's interval to 5000!

Dim flgFlashControl As Boolean
 
Private Function RunWalkthrough_0_1()
    'Explain the display
    Call FlashForm(frmControlHead)
   'Do stuff.... lalala
    Call StopFlashControl
End Function
 
Public Sub FlashForm(frmForm As Form, Optional ColourFlash = -1)
On Error Resume Next
    'Flash form between two colours every second
    Call writing
    
    'Set flash colour and original colour
    Dim OriginalColour As Long, FlashColour As Long
    FlashColour = IIf((ColourFlash < 0), DEFAULT_FLASH_COLOUR, ColourFlash)
    OriginalColour = frmForm.BackColor
    
    'Flash form
    DoEvents
    Do While (flgFlashControl = True)
        DoEvents
        'Swap colours
        If frmForm.BackColor = FlashColour Then
            frmForm.BackColor = OriginalColour
        Else
            frmForm.BackColor = FlashColour
        End If
        'Wait
        PauseMe (10000)
    Loop
    DoEvents
    'Return form colour
    frmForm.BackColor = OriginalColour
End Sub
 
Public Sub StopFlashControl()
    'Reset flashing flag
    flgFlashControl = False
End Sub
 
'Pause system in a loop temporarily
Public Sub PauseMe(lngPauseDuration As Long)
DoEvents
    Dim i As Long
    Do Until i = lngPauseDuration
        DoEvents
        i = i + 1
        DoEvents
    DoEvents
    Loop
    DoEvents
End Sub
 
Private Sub Command1_Click()
flgFlashControl = True
Call FlashForm(Me, red)
End Sub
 
 
Public Sub writing()
Timer1.Enabled = True
End Sub
 
Private Sub Timer1_Timer()
Text1.Text = "jbjabsdlvkbas"
flgFlashControl = False
End Sub

The Writing sub doesnt have to be launching a timer it could play music as well!

b

[rudvs2]

Best solution

Ditch vb6 get vb.net and use multithreading to solve your problem

Much less code too



Glad to be of service to ya

[Bruce Fox]

RJ,

Is there an event for the Audio file 'Finished'/'Load Complete' (or whatever it is) ?

[rjlohan]

Only if I use that MCI control, which I'm not.
I'm using sndPlaySound API. I'm sure I had a reason at some stage.

[Beacon]

i assume my way didnt work for you?

[rjlohan]

Wasn't really appropriate to the situation I'm afraid.

I'm thinking I may try the MCI control, and use its events to help me. But that will only work if I can implement function pointers in VB. Is that possible?

[Beacon]

Originally posted by rjlohan
Wasn't really appropriate to the situation I'm afraid.

I'm thinking I may try the MCI control, and use its events to help me. But that will only work if I can implement function pointers in VB. Is that possible?

What there's a situation where a carton of beer doesnt help??

*covers ears*

[rjlohan]

When did you say anything about beer??