JList scroll bug?

Question

I don't know if this is just when I'm using the the DefaultListModel instead of a vector , but the issue is that when I make my JList & JScrollPane, the scrollbars show correctly but i cannot scroll even though there are enough elements to fill the full window.

Source code:

panel_unit.add(YUi.JScrollPane(list = YUi.JList(main.config.fdata,0,0,this,0),500,314,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS),5,5);
public static JList JList(DefaultListModel text,int width,int height,ListSelectionListener listener,int SelIndex) {
    JList list = new JList(text);
    list.setPreferredSize(new Dimension(width,height));
    list.setSelectedIndex(SelIndex);
    list.addListSelectionListener(listener);
    return list;
}
public static JScrollPane JScrollPane(Component text,int width,int height,int HorizontalScrollBarPolicy,int VerticalScrollBarPolicy) {
    JScrollPane scrollpane = new JScrollPane(text);
    scrollpane.setPreferredSize(new Dimension(width,height));
    scrollpane.setHorizontalScrollBarPolicy(HorizontalScrollBarPolicy);
    scrollpane.setVerticalScrollBarPolicy(VerticalScrollBarPolicy);
    return scrollpane;
}

Answer 1

It probably has to do with your use of setting the preferred size, and using JScrollPane.VERTICAL_SCROLLBAR_ALWAYS. If you put that constant there it will always show a scrollbar regardless of if you can scroll or not.

Just try and I bet it will work:

new JScrollPane( list );

Answer 2

You should wrap your JScrollPane around the JList

Example:

JScrollPane scrollpane = new JScrollPane(list);

PS: The naming conventions you are using are not appropriate at all!!!

Answer 3

Steps are :

1. Create the JList component , called let's say "myJList" .

2. Create the JScrollPane component, using your JListComponent : JScrollPane myScrollPane = new JScrollPane(myJList);

3. Add only the JScrollPane to the GUI : .add(myScrollPane)