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JavaFX ListView

The ListView is a container for a list of items. If there are more items in the list than can be

shown, the list scrolls.

The items in the list can be set through the list's "items" property which is an instance of an

"ObservableList".

If we want to know which item in the list is selected, we can ask the list of its selection model and

from that model ask for the selected index or selected item.

For example:

list.getSelectonModel().getSelectedIndex();

If we want to know when a selection changes, we can use the "selectedItemProperty" of the

selection model and add a listener to it.

list.getSelectionModel().selectedItemProperty().addListener(new ChangeListener …);

The ChangeListener has a method called changed:

changed(Observable<? extends T> observable, T oldValue, T newValue)

The visualization for an entry in the list is controlled by the "CellFactory". This is a property

on the List that can be set. JavaFX provides some existing instances including:

• CheckBoxCellList

• ChoiceBoxCellList

• ComboBoxCellList

• TextFieldCellList

The default visualization of a list entry is simply the string representation of the item contained

within. We can define our own visualizer using the "setCellFactory()" method. This

method takes a Callback() object that must return an instance of a ListCell object. It is this

object that is the visualization and describes how to show data.

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