Class ExpandBar

All Implemented Interfaces:
Adaptable, Drawable

public class ExpandBar extends Composite
Instances of this class support the layout of selectable expand bar items.

The item children that may be added to instances of this class must be of type ExpandItem.

Styles:
V_SCROLL
Events:
Expand, Collapse

IMPORTANT: This class is not intended to be subclassed.

Since:
1.2
See Also:
  • Constructor Details

    • ExpandBar

      public ExpandBar(Composite parent, int style)
      Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.

      The style value is either one of the style constants defined in class SWT which is applicable to instances of this class, or must be built by bitwise OR'ing together (that is, using the int "|" operator) two or more of those SWT style constants. The class description lists the style constants that are applicable to the class. Style bits are also inherited from superclasses.

      Parameters:
      parent - a composite control which will be the parent of the new instance (cannot be null)
      style - the style of control to construct
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the parent is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
      • ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
      See Also:
  • Method Details

    • addExpandListener

      public void addExpandListener(ExpandListener listener)
      Adds the listener to the collection of listeners who will be notified when an item in the receiver is expanded or collapsed by sending it one of the messages defined in the ExpandListener interface.
      Parameters:
      listener - the listener which should be notified
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      See Also:
    • removeExpandListener

      public void removeExpandListener(ExpandListener listener)
      Removes the listener from the collection of listeners who will be notified when items in the receiver are expanded or collapsed.
      Parameters:
      listener - the listener which should no longer be notified
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      See Also:
    • computeSize

      public Point computeSize(int wHint, int hHint, boolean changed)
      Description copied from class: Control
      Returns the preferred size of the receiver.

      The preferred size of a control is the size that it would best be displayed at. The width hint and height hint arguments allow the caller to ask a control questions such as "Given a particular width, how high does the control need to be to show all of the contents?" To indicate that the caller does not wish to constrain a particular dimension, the constant SWT.DEFAULT is passed for the hint.

      If the changed flag is true, it indicates that the receiver's contents have changed, therefore any caches that a layout manager containing the control may have been keeping need to be flushed. When the control is resized, the changed flag will be false, so layout manager caches can be retained.

      Overrides:
      computeSize in class Composite
      Parameters:
      wHint - the width hint (can be SWT.DEFAULT)
      hHint - the height hint (can be SWT.DEFAULT)
      changed - true if the control's contents have changed, and false otherwise
      Returns:
      the preferred size of the control.
      See Also:
    • getItem

      public ExpandItem getItem(int index)
      Returns the item at the given, zero-relative index in the receiver. Throws an exception if the index is out of range.
      Parameters:
      index - the index of the item to return
      Returns:
      the item at the given index
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getItemCount

      public int getItemCount()
      Returns the number of items contained in the receiver.
      Returns:
      the number of items
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getItems

      public ExpandItem[] getItems()
      Returns an array of ExpandItems which are the items in the receiver.

      Note: This is not the actual structure used by the receiver to maintain its list of items, so modifying the array will not affect the receiver.

      Returns:
      the items in the receiver
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getSpacing

      public int getSpacing()
      Returns the receiver's spacing.
      Returns:
      the spacing
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • indexOf

      public int indexOf(ExpandItem item)
      Searches the receiver's list starting at the first item (index 0) until an item is found that is equal to the argument, and returns the index of that item. If no item is found, returns -1.
      Parameters:
      item - the search item
      Returns:
      the index of the item
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the item is null
      • ERROR_INVALID_ARGUMENT - if the item has been disposed
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • setSpacing

      public void setSpacing(int spacing)
      Sets the receiver's spacing. Spacing specifies the number of pixels allocated around each item.
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • setOrientation

      public void setOrientation(int orientation)
      Description copied from class: Control
      Sets the orientation of the receiver, which must be one of the constants SWT.LEFT_TO_RIGHT or SWT.RIGHT_TO_LEFT.
      Overrides:
      setOrientation in class Control
      Parameters:
      orientation - new orientation style
    • setData

      public void setData(String key, Object value)
      Description copied from class: Widget
      Sets the application defined property of the receiver with the specified name to the given value.

      Applications may associate arbitrary objects with the receiver in this fashion. If the objects stored in the properties need to be notified when the widget is disposed of, it is the application's responsibility to hook the Dispose event on the widget and do so.

      Overrides:
      setData in class Control
      Parameters:
      key - the name of the property
      value - the new value for the property
      See Also:
    • checkSubclass

      protected void checkSubclass()
      Description copied from class: Widget
      Checks that this class can be subclassed.

      The SWT class library is intended to be subclassed only at specific, controlled points (most notably, Composite and Canvas when implementing new widgets). This method enforces this rule unless it is overridden.

      IMPORTANT: By providing an implementation of this method that allows a subclass of a class which does not normally allow subclassing to be created, the implementer agrees to be fully responsible for the fact that any such subclass will likely fail between SWT releases and will be strongly platform specific. No support is provided for user-written classes which are implemented in this fashion.

      The ability to subclass outside of the allowed SWT classes is intended purely to enable those not on the SWT development team to implement patches in order to get around specific limitations in advance of when those limitations can be addressed by the team. Subclassing should not be attempted without an intimate and detailed understanding of the hierarchy.

      Overrides:
      checkSubclass in class Widget
    • getAdapter

      public <T> T getAdapter(Class<T> adapter)
      Description copied from class: Widget
      Implementation of the Adaptable interface.

      IMPORTANT: This method is not part of the RWT public API. It is marked public only so that it can be shared within the packages provided by RWT. It should never be accessed from application code.

      Specified by:
      getAdapter in interface Adaptable
      Overrides:
      getAdapter in class Composite
      Parameters:
      adapter - the lookup class
      Returns:
      an object that can be cast to the given class or null if there is no adapter associated with the given class.