javax.swing
Class DefaultComboBoxModel

java.lang.Object
  extended by javax.swing.AbstractListModel
      extended by javax.swing.DefaultComboBoxModel
All Implemented Interfaces:
Serializable, ComboBoxModel, ListModel, MutableComboBoxModel

public class DefaultComboBoxModel
extends AbstractListModel
implements MutableComboBoxModel, Serializable

A model that stores a list of elements and a selected item (which may be null). Changes to the model are signalled to listeners using ListDataEvent. This model is designed for use by the JComboBox component.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class javax.swing.AbstractListModel
listenerList
 
Constructor Summary
DefaultComboBoxModel()
          Creates a new model, initially empty.
DefaultComboBoxModel(Object[] items)
          Creates a new model and initializes its item list to the values in the given array.
DefaultComboBoxModel(Vector<?> vector)
          Creates a new model and initializes its item list to the values in the given vector.
 
Method Summary
 void addElement(Object object)
          Adds an element to the model's item list and sends a ListDataEvent to all registered listeners.
 Object getElementAt(int index)
          Returns the element at the specified index in the model's item list.
 int getIndexOf(Object object)
          Returns the index of the specified element in the model's item list.
 Object getSelectedItem()
          Returns the selected item.
 int getSize()
          Returns the number of items in the model's item list.
 void insertElementAt(Object object, int index)
          Adds an element at the specified index in the model's item list and sends a ListDataEvent to all registered listeners.
 void removeAllElements()
          Removes all the items from the model's item list, resets and selected item to null, and sends a ListDataEvent to all registered listeners.
 void removeElement(Object object)
          Removes an element from the model's item list and sends a ListDataEvent to all registered listeners.
 void removeElementAt(int index)
          Removes the element at the specified index from the model's item list and sends a ListDataEvent to all registered listeners.
 void setSelectedItem(Object object)
          Sets the selected item for the model and sends a ListDataEvent to all registered listeners.
 
Methods inherited from class javax.swing.AbstractListModel
addListDataListener, fireContentsChanged, fireIntervalAdded, fireIntervalRemoved, getListDataListeners, getListeners, removeListDataListener
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface javax.swing.ListModel
addListDataListener, removeListDataListener
 

Constructor Detail

DefaultComboBoxModel

public DefaultComboBoxModel()
Creates a new model, initially empty.


DefaultComboBoxModel

public DefaultComboBoxModel(Object[] items)
Creates a new model and initializes its item list to the values in the given array. The selected item is set to the first item in the array, or null if the array length is zero.

Parameters:
items - an array containing items for the model (null not permitted).
Throws:
NullPointerException - if items is null.

DefaultComboBoxModel

public DefaultComboBoxModel(Vector<?> vector)
Creates a new model and initializes its item list to the values in the given vector. The selected item is set to the first item in the vector, or null if the vector length is zero.

Parameters:
vector - a vector containing items for the model (null not permitted).
Throws:
NullPointerException - if vector is null.
Method Detail

addElement

public void addElement(Object object)
Adds an element to the model's item list and sends a ListDataEvent to all registered listeners. If the new element is the first item added to the list, and the selected item is null, the new element is set as the selected item.

Specified by:
addElement in interface MutableComboBoxModel
Parameters:
object - item to add to the model's item list.

removeElementAt

public void removeElementAt(int index)
Removes the element at the specified index from the model's item list and sends a ListDataEvent to all registered listeners. If the element removed was the selected item, then the preceding element becomes the new selected item (or the next element, if there is no preceding element).

Specified by:
removeElementAt in interface MutableComboBoxModel
Parameters:
index - the index of the item to remove.
Throws:
ArrayIndexOutOfBoundsException - if index is out of bounds.

insertElementAt

public void insertElementAt(Object object,
                            int index)
Adds an element at the specified index in the model's item list and sends a ListDataEvent to all registered listeners.

Specified by:
insertElementAt in interface MutableComboBoxModel
Parameters:
object - element to insert
index - index specifing position in the list where given element should be inserted.
Throws:
ArrayIndexOutOfBoundsException - if index is out of bounds.
See Also:
addElement(Object)

removeElement

public void removeElement(Object object)
Removes an element from the model's item list and sends a ListDataEvent to all registered listeners. If the item to be removed is the current selected item, a new selected item will be set. If the element is not found in the model's item list, this method does nothing.

Specified by:
removeElement in interface MutableComboBoxModel
Parameters:
object - the element to remove.

removeAllElements

public void removeAllElements()
Removes all the items from the model's item list, resets and selected item to null, and sends a ListDataEvent to all registered listeners.


getSize

public int getSize()
Returns the number of items in the model's item list.

Specified by:
getSize in interface ListModel
Returns:
The number of items in the model's item list.

setSelectedItem

public void setSelectedItem(Object object)
Sets the selected item for the model and sends a ListDataEvent to all registered listeners. The start and end index of the event is set to -1 to indicate the model's selection has changed, and not its contents.

Specified by:
setSelectedItem in interface ComboBoxModel
Parameters:
object - the new selected item (null permitted).

getSelectedItem

public Object getSelectedItem()
Returns the selected item.

Specified by:
getSelectedItem in interface ComboBoxModel
Returns:
The selected item (possibly null).

getElementAt

public Object getElementAt(int index)
Returns the element at the specified index in the model's item list.

Specified by:
getElementAt in interface ListModel
Parameters:
index - the element index.
Returns:
The element at the specified index in the model's item list, or null if the index is outside the bounds of the list.

getIndexOf

public int getIndexOf(Object object)
Returns the index of the specified element in the model's item list.

Parameters:
object - the element.
Returns:
The index of the specified element in the model's item list.