ButtonGroup: Quantity of selected elements

Question

How do I get the quantity of all selected JToggleButtons in a ButtonGroup?

ButtonGroup bGroup = new ButtonGroup();
bGreen = new JToggleButton("Green");
bYellow = new JToggleButton("Yellow");
bRed = new JToggleButton("Red");

bGroup.add(bGreen);
bGroup.add(bYellow);
bGroup.add(bRed);

Answer 1

There are several ways. For example bGroup.getSelection().getSelectedObjects().length. You can also call getElements(), then iterate over enumeration and ask isSelected() for each button. Please refer to API doc.

Answer 2

You have to add a item listener to each of the toogle

public int counter = 0;
public void itemStateChanged(ItemEvent e) {
    if(e.getStateChange() == ItemEvent.SELECTED)
    {
         counter++;
    }
    else
    {
        counter --;
    } 
}