How to access a VSTGUI control programmatically?

Developer VSTGUI
1

The WYSIWYG editor for VSTGUI 4 works decent. I have integrated this out-of-the-box with the project generator app.

My only problem is, what to do, when I want to access a control from code? Where do the CControl objects live that I have defined in the *.uidesc JSON file?

I have seen that maybe sub-controllers give fine control, but it’s not clear how to set / register this to get hold on the view object.

I can create my own custom view with a factory, sure, but I was expecting something like this:

UIViewFactory->getViewById(someUniqueIDOrName) which will then provide the control for further updates. But it seems such thing does not exist?

What is the best approach to set a CTextLabel in VSTGUI editor and then updating the label’s text from code? How a developer can access the CTextLabel object: It seems to live somewhere, but I do not know where, so I’ll probably have to end up by creating a custom view inheriting CTextLabel - instead.

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2

See here for an example on how to create sub-controllers.

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3

I believe he wish to know how to retrieve pointer to the specific View on the GUI.
What are exactly subcontrollers?

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4

I am not an expert and this may be a bad way of doing things, but after much headscratching (and Googling and ChatGPTing) I got this function which I put in controller.cpp:

	CView* PD10_MyController::getControlFromTag(int32_t tagNum)
	{
		CView* result = nullptr;
		CView* root = edView->getFrame()->getView(0);	//this is the mother view
		vector<CControl*> controlViews;
		uint32_t nViews;

		if (CViewContainer* rootAsContainer = root->asViewContainer())
		{
			nViews = rootAsContainer->getChildViewsOfType<CControl>(controlViews);
			for (CControl* cntrl : controlViews)
			{
				if (cntrl->getTag() == tagNum)
				{
					result = cntrl;
				}
			}
		}

		return result;
	}

This assumes the control has a tag, and tagnum is the tag number while edview is the editor view which is a copy of variable view in the createview(FIDString name) method. It seems unnecessarily difficult and maybe one is supposed to have some different paradigm but I’m finding documentation a trifle sparse. It would be nice to have just some collection of views/controls available but so far as I know there isn’t one.

Anyway hope this helps.

5

That’s indeed one of the most inefficient ways in doing it, but may work in your special case.
It’s more efficient when working with the IController::verifyView(..) method and remember the control with the tag in a member variable.

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6

Well I’m sure it is inefficient, but honestly the documentation is somewhat sparse. It’s like searching for needles in a haystack. Maybe Steinberg could make it more comprehensive so that n00bs like me don’t have to flounder around just trying to grasp the API?

7

Here’s a concrete example of using verifyView (and viewIsBeingDeleted, because you don’t want dangling pointers!)

CView* MyController::verifyView(CView* view, const UIAttributes& attributes, const IUIDescription* description)
{
	if (auto control = dynamic_cast<CTextLabel*>(view); control && control->getTag() == kMyTag)
	{
		myTextLabel = control;
	}

	return view;
}

void MyController::viewIsBeingDeleted(CView* view)
{
	if (view == myTextLabel)
		myTextLabel = nullptr;
}
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