Package	org.aswing
Class	public class JList
Inheritance	JList Container Component AWSprite flash.display.Sprite
Implements	LayoutManager, ListDataListener, Viewportable

A component that allows the user to select one or more objects from a list. A separate model, ListModel, represents the contents of the list. It's easy to display an array objects, using a JList constructor that builds a ListModel instance for you:

 // Create a JList that displays the strings in data[]
  var data:Array = ["one", "two", "three", "four"];
 var dataList:JList = new JList(data);
 
 // The value of the JList model property is an object that provides
 // a read-only view of the data.  It was constructed automatically.
  for(int i = 0; i < dataList.getModel().getSize(); i++) {
     System.out.println(dataList.getModel().getElementAt(i));
 }
  // Create a JList that displays the values in a IVector--VectorListModel.
  var vec:VectorListModel = new VectorListModel(["one", "two", "three", "four"]);
 var vecList:JList = new JList(vec);
 
 //When you add elements to the vector, the JList will be automatically updated.
 vec.append("five");
 

JList doesn't support scrolling directly. To create a scrolling list you make the JList the viewport of a JScrollPane. For example:

 JScrollPane scrollPane = new JScrollPane(dataList);
 // Or in two steps:
 JScrollPane scrollPane = new JScrollPane();
 scrollPane.setView(dataList);
 

By default the JList selection model is SINGLE_SELECTION.

 String[] data = {"one", "two", "three", "four"};
 JList dataList = new JList(data);
  dataList.setSelectedIndex(1);  // select "two"
 dataList.getSelectedValue();   // returns "two"
 

The contents of a JList can be dynamic, in other words, the list elements can change value and the size of the list can change after the JList has been created. The JList observes changes in its model with a ListDataListener implementation. A correct implementation of ListModel notifies it's listeners each time a change occurs. The changes are characterized by a ListDataEvent, which identifies the range of list indices that have been modified, added, or removed. Simple dynamic-content JList applications can use the VectorListModel class to store list elements. This class implements the ListModel and IVector interfaces and provides the Vector API. Applications that need to provide custom ListModel implementations can subclass AbstractListModel, which provides basic ListDataListener support.

JList uses a Component provision, provided by a delegate called the ListCell, to paint the visible cells in the list.

ListCell created by a ListCellFactory, to custom the item representation of the list, you need a custom ListCellFactory. For example a IconListCellFactory create IconListCells.

ListCellFactory is related to the List's performace too, see the doc comments of ListCellFactory for the details. And if you want a horizontal scrollvar visible when item width is bigger than the visible width, you need a not shareCells Factory(and of course the List should located in a JScrollPane first). shareCells Factory can not count the maximum width of list items.

See also

---