org.jfree.ui

Class KeyedComboBoxModel

Implemented Interfaces:
ComboBoxModel

public class KeyedComboBoxModel
extends java.lang.Object
implements ComboBoxModel

The KeyedComboBox model allows to define an internal key (the data element) for every entry in the model.

This class is usefull in all cases, where the public text differs from the internal view on the data. A separation between presentation data and processing data is a prequesite for localizing combobox entries. This model does not allow selected elements, which are not in the list of valid elements.

Author:
Thomas Morgner

Constructor Summary

KeyedComboBoxModel()
Creates a new keyed combobox model.
KeyedComboBoxModel(Object[] keys, Object[] values)
Creates a new keyed combobox model for the given keys and values.

Method Summary

void
add(Object key, Object cbitem)
Adds a new entry to the model.
void
addListDataListener(ListDataListener l)
Adds a listener to the list that's notified each time a change to the data model occurs.
void
clear()
Removes all entries from the model.
int
findElementIndex(Object key)
Tries to find the index of element with the given key.
protected void
fireListDataEvent(ListDataEvent evt)
Notifies all registered list data listener of the given event.
Object
getElementAt(int index)
Returns the value at the specified index.
Object
getKeyAt(int index)
Returns the key from the given index.
Object
getSelectedItem()
Returns the selected item.
Object
getSelectedKey()
Returns the selected data element or null if none is set.
int
getSize()
Returns the length of the list.
void
removeDataElement(Object key)
Removes an entry from the model.
void
removeListDataListener(ListDataListener l)
Removes a listener from the list that's notified each time a change to the data model occurs.
void
setData(Object[] keys, Object[] values)
Replaces the data in this combobox model.
void
setSelectedItem(Object anItem)
Set the selected item.
void
setSelectedKey(Object anItem)
Defines the selected key.

Constructor Details

KeyedComboBoxModel

public KeyedComboBoxModel()
Creates a new keyed combobox model.

KeyedComboBoxModel

public KeyedComboBoxModel(Object[] keys,
                          Object[] values)
Creates a new keyed combobox model for the given keys and values. Keys and values must have the same number of items.
Parameters:
keys - the keys
values - the values

Method Details

add

public void add(Object key,
                Object cbitem)
Adds a new entry to the model.
Parameters:
key - the key
cbitem - the display value.

addListDataListener

public void addListDataListener(ListDataListener l)
Adds a listener to the list that's notified each time a change to the data model occurs.
Parameters:
l - the ListDataListener to be added

clear

public void clear()
Removes all entries from the model.

findElementIndex

public int findElementIndex(Object key)
Tries to find the index of element with the given key. The key must not be null.
Parameters:
key - the key for the element to be searched.
Returns:
the index of the key, or -1 if not found.

fireListDataEvent

protected void fireListDataEvent(ListDataEvent evt)
Notifies all registered list data listener of the given event.
Parameters:
evt - the event.

getElementAt

public Object getElementAt(int index)
Returns the value at the specified index.
Parameters:
index - the requested index
Returns:
the value at index

getKeyAt

public Object getKeyAt(int index)
Returns the key from the given index.
Parameters:
index - the index of the key.
Returns:
the the key at the specified index.

getSelectedItem

public Object getSelectedItem()
Returns the selected item.
Returns:
The selected item or null if there is no selection

getSelectedKey

public Object getSelectedKey()
Returns the selected data element or null if none is set.
Returns:
the selected data element.

getSize

public int getSize()
Returns the length of the list.
Returns:
the length of the list

removeDataElement

public void removeDataElement(Object key)
Removes an entry from the model.
Parameters:
key - the key

removeListDataListener

public void removeListDataListener(ListDataListener l)
Removes a listener from the list that's notified each time a change to the data model occurs.
Parameters:
l - the ListDataListener to be removed

setData

public void setData(Object[] keys,
                    Object[] values)
Replaces the data in this combobox model. The number of keys must be equals to the number of values.
Parameters:
keys - the keys
values - the values

setSelectedItem

public void setSelectedItem(Object anItem)
Set the selected item. The implementation of this method should notify all registered ListDataListeners that the contents have changed.
Parameters:
anItem - the list object to select or null to clear the selection

setSelectedKey

public void setSelectedKey(Object anItem)
Defines the selected key. If the object is not in the list of values, no item gets selected.
Parameters:
anItem - the new selected item.