How to change state of TGSplitButton?

ROOT
1

Hello,

I would like to change the state of a (truly split) TGSplitButton. I could not find any method to influence the state of the button (i.e. which of the menu items is displayed on the button). I have also tried (brute force) via the menu attached to the TGSplitButton, e.g. deleting a menu entry and later adding it, but this only seems to confuse the TGSplitButton, ending in a segementation violation.

Example:

    fMenu = new TGPopupMenu(gClient->GetRoot());
    fMenu->AddEntry("Item 1", M_ITEM1);
    fMenu->AddEntry("Item 2", M_ITEM2);
   
    fSplitButton = new TGSplitButton(fFrame, new TGHotString("Split Button"), 
					fMenu, kTRUE, splitButtonID);

    fSplitButton->Connect("ItemClicked(Int_t)", "MyClass", this, "DoButton(Int_t)");
    fMenu->Connect("Activated(Int_t)", "MyClass", this,"DoMenu(Int_t)");

Now, what I want is when the user selects “Item2”, something happens, but the button STAYS on item1! Therefore, in DoMenu(), I try something like

    case M_ITEM2:
     {   
        // launch some window
        new Dialog(bla);
        // make sure fSplitButton stays on Item1 - the only way I can think of:
        TGHotString* label = fMenu->GetEntry(M_ITEM2)->GetLabel();
        fMenu->DeleteEntry(M_ITEM2);
        fMenu->AddEntry(label, M_ITEM2); 
     }

But this results in a seg. viol. Is there really no way to change the status of a split button other than clicking on it? Am I using the wrong widget for this? (If I could change its state, it would be the perfect widget for my application…) Does anyone have an idea?

Many thanks,

Thomas

2

Hi Thomas,
You are right, there is no API to do this. We will put it in our ToDo list.
Cheers, Bertrand.