Custom control: slider with two needles

[vix]

I've been using LabVIEW for some years, and I was able to create a lot of custom controls.

I know that CVI is doesn't allow me such a level of customization, but I don't know if there is a simple and effective way to create a slider controls with two needles (based on the Vertical Pointer Slide for example).

I used two different overlapped slides, and they behave more or less as I expected (not fully satisfied, but ...). I need placing a lot of these controls in a panel, so I wonder if I can group the two slides in a custom control, and write some c code to interface with them (if I select Create >>Custom control, I can't select two different controls...)

Is there another way to create a slider control with two needles?

[Wolfgang]

Hi,

did you consider building your control externally (LabView??) and then use it as an ActiveX control element in CVI?

[vix]

Is there any available documentation on how to do what you suggest?

[Wolfgang]

Well, this comment consists of two steps: creation and usage of the ActiveX control.

For the latter there are several examples available in the CVI distribution, but I cannot assist in how to create such a control in LabView - From your post I assumed that you have designed (or knew how to design) a suitable control in LabView - and I thought that it should be possible to export it, however without any clue of how this might be accomplished in reality. All I am aware of are the examples in CVI using such controls, e.g. the 3D graph...

[vix]

Yes, I know how to design such a control in LabVIEW, and I think I can learn how to use it in CVI.

The problem is that I don't think a LabVIEW control could be exported as an ActiveX control...

[nickb]

Hey Vix - 

While I agree it's not quite as straightforward as LabVIEW, you can do exactly what you're talking about with LabWindows/CVI.  The basic instructions to do this are here.  Another good resource is to check out the installed custom controls in <CVI>\toolslib\custctrl, and copy their format.  It sounds like for your particular case, you'd want to create a custom control for a slide control.  Then, in the API for your custom control, you could have a convert function that programmatically created the second slide control for your second needle.  If you need more detail than this, let me know. 

NickB

National Instruments 

[ebalci]

Hi,

If you ask me, I would say there really should be something like an online video tutorial about CVI custom controls.

I myself struggled with it and I do not remember coming up with something useful.

I found the process -as explained in the link Nick provided- unintuitive and hard to control.

It was kinda disappointing for me.