"David V. Fansler" <DavidVFans***@discussions.microsoft.com> wrote in
message news:FC1A2129-BB48-4FE5-A6D8-A4B0F38093D5@microsoft.com...
>I am trying to make a contribution to an open VB6 program.  As the program
> was written it sets up a FlexGrid where the columns are time intervals and
> the rows are individual light channels.  A cell is set to one for a
> channel
> to be one during a time interval and set to 0 for a channel to be off
> during
> time interval.  The grid looks like an Excel spreadsheet where you simply
> click on a grid to a cell on or off.  Data is output, an interval at a
> time
> to a bit on the parallel printer port (using geekhideout_io.bas as a base
> dll).  A new dll was written specific to the control hardware.
>
> What I am trying to do is to read data back in (as data is going out) on a
> different parallel printer port pin, and write this data back to the
> FlexGrid.  I am trying to do this from the new dll so that timing between
> the
> outgoing data and the incoming data will remain in sync.  Capturing the
> data
> is not a problem.  Writing the data back to the flex grid is.
>
> In the main program, when a cell is turned on or off, a call is made
> CometMod.currentSong.setCell(MusicGrid, .row, .col, 0)  where MusicGrid is
> the FlexGrid, .row & .col are the row and column of the cell and the 0
> turns
> the cell off, where a 1 would turn it on.  This same function turns the
> background of the cell white for off and black for on.  Attempts to call
> this
> function from the dll have failed with a Run time error of '424 object
> required'.  I was not really expecting it to work - but hoping it would.
>
> So it is it possible to write back to a FlexGrid located in the main
> program
> from a dll that has been called from the main program?
>
> As a disclaimer, I know some about VB, but I am not an expert.  Plus, I do
> not pretend to understand all the intricacies of the program I am trying
> to
> add to.
>
> My thanks for all help.
> David
>

>
> Are you talking about ActiveX dll or it is "true" dll?
>
> If it is ActiveX dll then you can raise event from one of public classes
> within your dll. In the client you should have instance of that class
> declared with WithEvents keyword.
>
> If it is "true" dll, then you can use callback technique - when you pass
> address of some function with predefined signature to the dll (procedure
> should be defined in regular module), and then dll calls this procedure by
> given address.
>
> Dmitriy.
>
>
>

"David V. Fansler" <DavidVFans***@discussions.microsoft.com> wrote in
message news:8833A936-0765-41DD-9238-22927002616D@microsoft.com...
>
>
> "Dmitriy Antonov" wrote:
> Hi Dmitriy - As a novice, I am not sure of the difference betweena an
> ActiveX or a true dll.  I believe the geekhideout_io.dll is done in
> assmebly
> and can be called from any program.  It handles the IO to any port on the
> computer.   The dll which I have the source for was done in VB6.  This dll
> sets the port to be the address of your printer port and uses calls to the
> geekhideout_io.dll to ouput and input from the printer port.
>
> To be honest, I have not yet found where the main VB program calls the dll
> called by the VB program.  The progam uses the timer function of the
> Windows
> Media Player to determine the current interval.
>
> Is this enough infor to determine if I am using an ActiveX or true dll?
> If
> so, could you expound on your answer on how to return data?
> Thanks,
> David
>>
>> Are you talking about ActiveX dll or it is "true" dll?
>>
>> If it is ActiveX dll then you can raise event from one of public classes
>> within your dll. In the client you should have instance of that class
>> declared with WithEvents keyword.
>>
>> If it is "true" dll, then you can use callback technique - when you pass
>> address of some function with predefined signature to the dll (procedure
>> should be defined in regular module), and then dll calls this procedure
>> by
>> given address.
>>
>> Dmitriy.
>>

"Dmitriy Antonov" wrote:

>
> "David V. Fansler" <DavidVFans***@discussions.microsoft.com> wrote in
> message news:8833A936-0765-41DD-9238-22927002616D@microsoft.com...
> >
> >
> > "Dmitriy Antonov" wrote:
> > Hi Dmitriy - As a novice, I am not sure of the difference betweena an
> > ActiveX or a true dll.  I believe the geekhideout_io.dll is done in
> > assmebly
> > and can be called from any program.  It handles the IO to any port on the
> > computer.   The dll which I have the source for was done in VB6.  This dll
> > sets the port to be the address of your printer port and uses calls to the
> > geekhideout_io.dll to ouput and input from the printer port.
> >
> > To be honest, I have not yet found where the main VB program calls the dll
> > called by the VB program.  The progam uses the timer function of the
> > Windows
> > Media Player to determine the current interval.
> >
> > Is this enough infor to determine if I am using an ActiveX or true dll?
> > If
> > so, could you expound on your answer on how to return data?
> > Thanks,
> > David
> >>
> >> Are you talking about ActiveX dll or it is "true" dll?
> >>
> >> If it is ActiveX dll then you can raise event from one of public classes
> >> within your dll. In the client you should have instance of that class
> >> declared with WithEvents keyword.
> >>
> >> If it is "true" dll, then you can use callback technique - when you pass
> >> address of some function with predefined signature to the dll (procedure
> >> should be defined in regular module), and then dll calls this procedure
> >> by
> >> given address.
> >>
> >> Dmitriy.
> >>
>
>
> As I understand, you want to send some notification to your "main"
> application from the dll, which you are currently working with and this one
> is being developed in VB. If true, then it is ActiveX.dll (there is no way
> to create regular DLLs in VB, so its simple to make such conclusion). So as
> I said, you can raise an event (which may contain parameters) from that dll
> and catch this event within your main application. Without knowing some
> details of your dll's construction, its hard to give you advise as to
> particular implementation. I think the best way to do is to refer you to the
> Help system or some (in fact, any) textbook for beginners. VB makes creation
> and use of events pretty trivial task and its hard to imagine that you can
> do something definite in VB without knowing this material - so you should
> study it anyway - the sooner the better (even if you never develop classes
> then you will not avoid usage of events created by someone else - so you
> must know how it works anyway).
>
> In minimal words your task is:
> 1. In your DLL
> 1a. In one of your public classes - define event along with necessary
> arguments. Since you make calls to this dll from your "main" application and
> you do it using some public class within your dll, then the first candidate
> for such event would be, perhaps, this class.
> 1b. When, during execution of some task within dll, there is time to notify
> caller, than you just use RaiseEvent method
>
> 2. In main application
> 2a declare object of mentioned class with WithEvents keywords (you can do it
> in module level only - can't use variables defined locally in procedures)
> 2b add event handler and add the code within this handler to response
> appropriately
>
> Definitely, it is essential that you have to know how both of your
> projects - main app and dll -work, nobody here can help you with this task.
>
> I don't know whether I could do more than that for you (as long as I
> understand your task correctly) .
>
> Dmitriy.
>
>
>
>
>
>