The Java Developers Almanac 1.4

Home > List of Packages > javax.swing [141 examples] > JList [12 examples]

e782. Arranging Items in a JList Component

By default, the items in a list are arranged vertically, in a single column, as in:

    item1
    item2
    ...

It is possible to arrange the items left-to-right and top-to-bottom, as in:

    item1    item2
    item3    item4
    item5    ...

This example creates and configures a list that displays its items left-to-right and top-to-bottom. Note that the number of columns can change as the width of the list changes.

    // Create a scrollable list
    String[] items = {"A", "B", "C", "D"};
    JList list = new JList(items);
    JScrollPane scrollingList = new JScrollPane(list);
    
    // The default layout orientation is JList.VERTICAL
    int orient = list.getLayoutOrientation();
    
    // Change the layout orientation to left-to-right, top-to-bottom
    list.setLayoutOrientation(JList.HORIZONTAL_WRAP);

The items can also be arranged top-to-bottom and left-to-right, as in:

    item1    item4
    item2    item5
    item3    ...

This example changes the layout orientation so that its items are displayed top-to-bottom and left-to-right.

    // Change orientation to top-to-bottom, left-to-right layout
    list.setLayoutOrientation(JList.VERTICAL_WRAP);

With some look and feels, a list is set to display a fixed number of rows. In order to make the number of visible rows dependent on the height of the list, the visibleRowCount property must be set to 0:

    // Make the number of rows dynamic
    list.setVisibleRowCount(0);