Class CheckBoxList<T>

All Implemented Interfaces:
ImageObserver, MenuContainer, Serializable, Accessible, Scrollable
Direct Known Subclasses:
BasicCheckBoxList, ControlStack

public abstract class CheckBoxList<T> extends JList<T>
JList subclass that adds a couple of features. First, each entry has a checkbox associated with it that may be selected or deselected by the user. Second, the list entries can be reordered by the user dragging them up or down in the list. A distinctive handle is provided to indicate this option visually. Third, you can overpaint a message below the list items.

The selection model for the checkboxes and the list model giving entry ordering are held externally to this implementation, so must be explicitly managed by clients of this class, and may be modified programmatically.

Since:
13 Mar 2013
Author:
Mark Taylor
See Also:
  • Constructor Details

    • CheckBoxList

      public CheckBoxList(ListModel<T> model, boolean canSelect, JComponent entryRenderer)
      Constructor. A renderer component is supplied; when entries need to be displayed the configureEntryRenderer method is called.
      Parameters:
      model - list model
      canSelect - true if list item selection is permitted
      entryRenderer - renderer for list entry contents (excluding drag and checkbox decorations)
  • Method Details

    • configureEntryRenderer

      protected abstract void configureEntryRenderer(JComponent entryRenderer, T item, int index)
      This method is called whenever the list cell needs to be painted.
      Parameters:
      entryRenderer - renderer object supplied at construction time
      item - list entry
      index - index in list at which entry appears
    • isChecked

      public abstract boolean isChecked(T item)
      Indicates whether the checkbox for a given item is selected.
      Parameters:
      item - list entry
      Returns:
      true iff item is selected
    • setChecked

      public abstract void setChecked(T item, boolean isChecked)
      Sets whether the checkbox for a given item is selected. Called when the user interacts with the checkbox. It is up to the concrete implementation to ensure that this is reflected by the isChecked method.
      Parameters:
      item - list entry
      isChecked - whether item should be selected
    • moveItem

      public abstract void moveItem(int ifrom, int ito)
      Indicates that the user has requested a reordering of the list model. It is up to the concrete implementation to ensure that this is reflected in the list model.
      Parameters:
      ifrom - source list index
      ito - destination list index
    • setCheckedAll

      public void setCheckedAll(boolean isChecked)
      Programmatically sets the checkbox status for all the items in the list.

      The default implementation calls setChecked for each item in the list, but subclasses may be able to override this for improved efficiency.

      Parameters:
      isChecked - true to check all, false to uncheck all
    • setListMessage

      public void setListMessage(String[] msgLines)
      Sets a message which is overpainted on the blank part of this component. If null or empty, no message is painted.
      Parameters:
      msgLines - lines of a message to paint
    • addListDataListener

      public void addListDataListener(ListDataListener l)
      Adds a listener for list events. As well as changes to the underlying ListModel, this will also be messaged when any of the elements becomes checked or unchecked.
      Parameters:
      l - listener to add
    • removeListDataListener

      public void removeListDataListener(ListDataListener l)
      Removes a listener previously added.
      Parameters:
      l - listener to remove
    • paintComponent

      protected void paintComponent(Graphics g)
      Overrides:
      paintComponent in class JComponent
    • createCheckAllAction

      public Action createCheckAllAction(boolean isChecked)
      Returns a new action that can be used to check or uncheck all the items in the list at once.
      Parameters:
      isChecked - true to check all, false to uncheck all