Class List

All Implemented Interfaces:
Adaptable, Drawable

public class List extends Scrollable
Instances of this class represent a selectable user interface object that displays a list of strings and issues notification when a string is selected. A list may be single or multi select.

Styles:
SINGLE, MULTI
Events:
Selection, DefaultSelection

Note: Only one of SINGLE and MULTI may be specified.

IMPORTANT: This class is not intended to be subclassed.

Since:
1.0
  • Constructor Details

    • List

      public List(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

    • 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 Control
      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.
    • getSelection

      public String[] getSelection()
      Returns an array of Strings that are currently selected in the receiver. The order of the items is unspecified. An empty array indicates that no items are selected.

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

      Returns:
      an array representing the selection
      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
    • getSelectionIndex

      public int getSelectionIndex()
      Returns the zero-relative index of the item which is currently selected in the receiver, or -1 if no item is selected.
      Returns:
      the index of the selected item or -1
      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
    • getSelectionIndices

      public int[] getSelectionIndices()
      Returns the zero-relative indices of the items which are currently selected in the receiver. The order of the indices is unspecified. The array is empty if no items are selected.

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

      Returns:
      the array of indices of the selected 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
    • getSelectionCount

      public int getSelectionCount()
      Returns the number of selected items contained in the receiver.
      Returns:
      the number of selected 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
    • setSelection

      public void setSelection(int selection)
      Selects the item at the given zero-relative index in the receiver. If the item at the index was already selected, it remains selected. The current selection is first cleared, then the new item is selected. Indices that are out of range are ignored.
      Parameters:
      selection - the index of the item to select
      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
      See Also:
    • setSelection

      public void setSelection(int[] selection)
      Selects the items at the given zero-relative indices in the receiver. The current selection is cleared before the new items are selected.

      Indices that are out of range and duplicate indices are ignored. If the receiver is single-select and multiple indices are specified, then all indices are ignored.

      Parameters:
      selection - the indices of the items to select
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the array of indices 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:
    • setSelection

      public void setSelection(int start, int end)
      Selects the items in the range specified by the given zero-relative indices in the receiver. The range of indices is inclusive. The current selection is cleared before the new items are selected.

      Indices that are out of range are ignored and no items will be selected if start is greater than end. If the receiver is single-select and there is more than one item in the given range, then all indices are ignored.

      Parameters:
      start - the start index of the items to select
      end - the end index of the items to select
      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
      See Also:
    • setSelection

      public void setSelection(String[] selection)
      Sets the receiver's selection to be the given array of items. The current selection is cleared before the new items are selected.

      Items that are not in the receiver are ignored. If the receiver is single-select and multiple items are specified, then all items are ignored.

      Parameters:
      selection - the array of items
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the array of items 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:
    • select

      public void select(int index)
      Selects the item at the given zero-relative index in the receiver's list. If the item at the index was already selected, it remains selected. Indices that are out of range are ignored.
      Parameters:
      index - the index of the item to select
      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
    • select

      public void select(int[] indices)
      Selects the items at the given zero-relative indices in the receiver. The current selection is not cleared before the new items are selected.

      If the item at a given index is not selected, it is selected. If the item at a given index was already selected, it remains selected. Indices that are out of range and duplicate indices are ignored. If the receiver is single-select and multiple indices are specified, then all indices are ignored.

      Parameters:
      indices - the array of indices for the items to select
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the array of indices 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:
    • select

      public void select(int start, int end)
      Selects the items in the range specified by the given zero-relative indices in the receiver. The range of indices is inclusive. The current selection is not cleared before the new items are selected.

      If an item in the given range is not selected, it is selected. If an item in the given range was already selected, it remains selected. Indices that are out of range are ignored and no items will be selected if start is greater than end. If the receiver is single-select and there is more than one item in the given range, then all indices are ignored.

      Parameters:
      start - the start of the range
      end - the end of the range
      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
      See Also:
    • selectAll

      public void selectAll()
      Selects all of the items in the receiver.

      If the receiver is single-select, do nothing.

      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
    • deselectAll

      public void deselectAll()
      Deselects all selected 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
    • deselect

      public void deselect(int index)
      Deselects the item at the given zero-relative index in the receiver. If the item at the index was already deselected, it remains deselected. Indices that are out of range are ignored.
      Parameters:
      index - the index of the item to deselect
      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
      Since:
      1.3
    • deselect

      public void deselect(int start, int end)
      Deselects the items at the given zero-relative indices in the receiver. If the item at the given zero-relative index in the receiver is selected, it is deselected. If the item at the index was not selected, it remains deselected. The range of the indices is inclusive. Indices that are out of range are ignored.
      Parameters:
      start - the start index of the items to deselect
      end - the end index of the items to deselect
      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
      Since:
      1.3
    • deselect

      public void deselect(int[] indices)
      Deselects the items at the given zero-relative indices in the receiver. If the item at the given zero-relative index in the receiver is selected, it is deselected. If the item at the index was not selected, it remains deselected. Indices that are out of range and duplicate indices are ignored.
      Parameters:
      indices - the array of indices for the items to deselect
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the set of indices 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
      Since:
      1.3
    • isSelected

      public boolean isSelected(int index)
      Returns true if the item is selected, and false otherwise. Indices out of range are ignored.
      Parameters:
      index - the index of the item
      Returns:
      the visibility state of the item at the index
      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
    • setTopIndex

      public void setTopIndex(int topIndex)
      Sets the zero-relative index of the item which is currently at the top of the receiver. This index can change when items are scrolled or new items are added and removed.
      Parameters:
      topIndex - the index of the top 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
      Since:
      1.3
    • getTopIndex

      public int getTopIndex()
      Returns the zero-relative index of the item which is currently at the top of the receiver. This index can change when items are scrolled or new items are added or removed.
      Returns:
      the index of the top 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
      Since:
      1.3
    • showSelection

      public void showSelection()
      Shows the selection. If the selection is already showing in the receiver, this method simply returns. Otherwise, the items are scrolled until the selection is visible.
      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
      Since:
      1.3
    • getFocusIndex

      public int getFocusIndex()
      Returns the zero-relative index of the item which currently has the focus in the receiver, or -1 if no item has focus.
      Returns:
      the index of the selected 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
    • add

      public void add(String string)
      Adds the argument to the end of the receiver's list.
      Parameters:
      string - the new item
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the string 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:
    • add

      public void add(String string, int index)
      Adds the argument to the receiver's list at the given zero-relative index.

      Note: To add an item at the end of the list, use the result of calling getItemCount() as the index or use add(String).

      Parameters:
      string - the new item
      index - the index for the item
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the string is null
      • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list (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
      See Also:
    • remove

      public void remove(int index)
      Removes the item from the receiver at the given zero-relative index.
      Parameters:
      index - the index for the item
      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
    • remove

      public void remove(int start, int end)
      Removes the items from the receiver which are between the given zero-relative start and end indices (inclusive).
      Parameters:
      start - the start of the range
      end - the end of the range
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_RANGE - if either the start or end are 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
    • remove

      public void remove(int[] indices)
      Removes the items from the receiver at the given zero-relative indices.
      Parameters:
      indices - the array of indices of the items
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
      • ERROR_NULL_ARGUMENT - if the indices array 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
    • remove

      public void remove(String string)
      Searches the receiver's list starting at the first item until an item is found that is equal to the argument, and removes that item from the list.
      Parameters:
      string - the item to remove
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the string is null
      • ERROR_INVALID_ARGUMENT - if the string is not found in the list
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • removeAll

      public void removeAll()
      Removes all of the items from 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
    • setItem

      public void setItem(int index, String string)
      Sets the text of the item in the receiver's list at the given zero-relative index to the string argument. This is equivalent to remove'ing the old item at the index, and then add'ing the new item at that index.
      Parameters:
      index - the index for the item
      string - the new text for the item
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
      • ERROR_NULL_ARGUMENT - if the string 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
    • setItems

      public void setItems(String[] items)
      Sets the receiver's items to be the given array of items.
      Parameters:
      items - the array of items
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the items array is null
      • ERROR_INVALID_ARGUMENT - if an item in the items array 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
    • getItem

      public String 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 String[] getItems()
      Returns a (possibly empty) array of Strings 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's list
      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(String string)
      Gets the index of an item.

      The list is searched starting at 0 until an item is found that is equal to the search item. If no item is found, -1 is returned. Indexing is zero based.

      Parameters:
      string - the search item
      Returns:
      the index of the item
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the string 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
    • indexOf

      public int indexOf(String string, int start)
      Searches the receiver's list starting at the given, zero-relative index until an item is found that is equal to the argument, and returns the index of that item. If no item is found or the starting index is out of range, returns -1.
      Parameters:
      string - the search item
      start - the zero-relative index at which to start the search
      Returns:
      the index of the item
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the string 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
    • getItemHeight

      public int getItemHeight()
      Returns the height of the area which would be used to display one of the items in the list.
      Returns:
      the height of one 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
    • addSelectionListener

      public void addSelectionListener(SelectionListener listener)
      Adds the listener to the collection of listeners who will be notified when the receiver's selection changes, by sending it one of the messages defined in the SelectionListener interface.

      widgetSelected is called when the selection changes. widgetDefaultSelected is typically called when an item is double-clicked.

      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:
    • removeSelectionListener

      public void removeSelectionListener(SelectionListener listener)
      Removes the listener from the collection of listeners who will be notified when the receiver's selection changes.
      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:
    • setFont

      public void setFont(Font font)
      Description copied from class: Control
      Sets the font that the receiver will use to paint textual information to the font specified by the argument, or to the default font for that kind of control if the argument is null.
      Overrides:
      setFont in class Control
      Parameters:
      font - the new font (or null)
    • 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:
    • 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 Control
      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: