Inherits from | |
Conforms to | |
Framework | /System/Library/Frameworks/AppKit.framework |
Availability | Available in Mac OS X v10.0 and later. |
Companion guide | |
Declared in | NSComboBoxCell.h |
NSComboBoxCell
is a subclass of NSTextFieldCell
used to implement the user interface of “combo boxes” (see NSComboBox for information on how combo boxes look and work). The NSComboBox
subclass of NSTextField
uses a single NSComboBoxCell
, and essentially all of the NSComboBox
class’ methods simply invoke the corresponding NSComboBoxCell
method.
Also see the NSComboBoxCellDataSource informal protocol, which declares the methods that an NSComboBoxCell
object uses to access the contents of its data source object.
– hasVerticalScroller
– isButtonBordered
– intercellSpacing
– itemHeight
– numberOfVisibleItems
– setButtonBordered:
– setHasVerticalScroller:
– setIntercellSpacing:
– setItemHeight:
– setNumberOfVisibleItems:
– addItemsWithObjectValues:
– addItemWithObjectValue:
– insertItemWithObjectValue:atIndex:
– objectValues
– removeAllItems
– removeItemAtIndex:
– removeItemWithObjectValue:
– numberOfItems
– indexOfItemWithObjectValue:
– itemObjectValueAtIndex:
– noteNumberOfItemsChanged
– reloadData
– scrollItemAtIndexToTop:
– scrollItemAtIndexToVisible:
– deselectItemAtIndex:
– indexOfSelectedItem
– objectValueOfSelectedItem
– selectItemAtIndex:
– selectItemWithObjectValue:
Adds multiple objects to the internal item list.
- (void)addItemsWithObjectValues:(NSArray *)objects
The object to add to the end of the receiver’s internal item list.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Adds the specified object to the internal item list.
- (void)addItemWithObjectValue:(id)anObject
The object to add to the end of the receiver's internal item list.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Returns a string from the receiver’s pop-up list that starts with the given substring.
- (NSString *)completedString:(NSString *)substring
The substring to search for. This is what the user entered in the combo box’s text field.
The string from the receiver's pop-up list that starts with the specified substring or nil
if there is no such string.
The default implementation of this method first checks whether the combo box uses a data source and whether the data source responds to comboBox:completedString:
or comboBoxCell:completedString:
. If so, the combo box cell returns that method’s return value. Otherwise, this method goes through the combo box’s items one by one and returns an item that starts with substring.
Override this method only if your subclass completes strings differently. The overriding method does not need to call the superclass’s method. Generally, you do not need to call this method directly.
NSComboBoxCell.h
Returns a Boolean value indicating whether the receiver tries to complete text entered by the user.
- (BOOL)completes
YES
if the receiver tries to complete what the user types in the text field; NO
otherwise.
NSComboBoxCell.h
Returns the object that provides the data displayed in the receiver’s pop-up list.
- (id)dataSource
The data source for the receiver's pop-up list.
This method logs a warning if usesDataSource
returns NO
. See the class description and the NSComboBoxCellDataSource informal protocol specification for more information on combo box cell data source objects.
NSComboBoxCell.h
Deselects the pop-up list item at the given index if it’s selected.
- (void)deselectItemAtIndex:(NSInteger)index
The index of the item to deselect.
If the selection does in fact change, this method posts an NSComboBoxSelectionDidChangeNotification
to the default notification center.
NSComboBoxCell.h
Encodes the receiver using the specified coder.
- (void)encodeWithCoder:(NSCoder *)encoder
The coder to use when encoding the receiver. If the receiver uses a data source, the data source is conditionally encoded as well.
NSComboBoxCell.h
Returns a Boolean value indicating whether the receiver will display a vertical scroller.
- (BOOL)hasVerticalScroller
YES
if the receiver displays a vertical scroller; otherwise NO
.
Note that the scroller will be displayed even if the pop-up list contains fewer items than will fit in the area specified for display.
NSComboBoxCell.h
Searches the receiver’s internal item list for the given object and returns the matching index number.
- (NSInteger)indexOfItemWithObjectValue:(id)anObject
The object for which to return the index.
The lowest index whose corresponding value is equal to anObject. Objects are considered equal if they have the same id or if isEqual:
returns YES
. If none of the objects in the receiver’s internal item list is equal to anObject, indexOfItemWithObjectValue:
returns NSNotFound
.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Returns the index of the last item selected from the pop-up list.
- (NSInteger)indexOfSelectedItem
The index of the last item selected from the receiver's pop-up list or –1 if no item is selected.
Note that nothing is initially selected in a newly initialized combo box cell.
NSComboBoxCell.h
Initializes a newly allocated instance from data in the specified coder.
- (id)initWithCoder:(NSCoder *)decoder
The coder from which to draw the data to initialize the combo box cell.
The initialized NSComboBoxCell
object.
If the decoded instance uses a data source, initWithCoder:
decodes the data source as well.
NSComboBoxCell.h
Inserts an object at the specified location in the internal item list.
- (void)insertItemWithObjectValue:(id)anObject atIndex:(NSInteger)index
The object to add to the receiver's internal item list.
The index at which to add the specified object. The previous item at index—along with all following items—is shifted down one slot to make room.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Returns the spacing between cells in the receiver’s pop-up list.
- (NSSize)intercellSpacing
The horizontal and vertical spacing between cells in the receiver’s pop-up list. The default spacing is (3.0, 2.0).
NSComboBoxCell.h
Returns a Boolean value indicating whether the combo box button is set to display a border.
- (BOOL)isButtonBordered
YES
if the button has a border; otherwise NO
.
NSComboBoxCell.h
Returns the height of each item in the receiver’s pop-up list.
- (CGFloat)itemHeight
The height of each item in the pop-up list. The default item height is 16.0.
NSComboBoxCell.h
Returns the object located at the specified location in the internal item list.
- (id)itemObjectValueAtIndex:(NSInteger)index
The index of the object to return. If index is beyond the end of the list, an NSRangeException
is raised.
The object at the given location in the receiver's internal item list.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Informs the receiver that the number of items in its data source has changed.
- (void)noteNumberOfItemsChanged
This method allows the receiver to update the scrollers in its displayed pop-up list without actually reloading data into the receiver. It is particularly useful for a data source that continually receives data in the background over a period of time, in which case the NSComboBoxCell
can remain responsive to the user while the data is received.
See the NSComboBoxCellDataSource
informal protocol specification for information on the messages an NSComboBoxCell
sends to its data source.
NSComboBoxCell.h
Returns the total number of items in the pop-up list.
- (NSInteger)numberOfItems
The number of items in the pop-up list.
– numberOfVisibleItems
– numberOfItemsInComboBoxCell:
(NSComboBoxCellDataSource protocol)NSComboBoxCell.h
Returns the maximum number of items visible in the pop-up list.
- (NSInteger)numberOfVisibleItems
The maximum number of items that are visible in the receiver's pop-up list at any one time.
NSComboBoxCell.h
Returns the object corresponding to the last item selected from the pop-up list.
- (id)objectValueOfSelectedItem
The object from the receiver’s internal item list corresponding to the last item selected from the pop-up list, or nil
if no item is selected.
Note that nothing is initially selected in a newly initialized combo box cell. This method logs a warning if usesDataSource
returns YES
.
– indexOfSelectedItem
– comboBoxCell:objectValueForItemAtIndex:
(NSComboBoxCellDataSource
protocol)NSComboBoxCell.h
Returns the receiver’s internal item list.
- (NSArray *)objectValues
An array containing the objects in the receiver's internal item list.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Marks the receiver as needing redisplay, so that it will reload the data for visible pop-up items and draw the new values.
- (void)reloadData
NSComboBoxCell.h
Removes all items from the receiver’s internal item list.
- (void)removeAllItems
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Removes the object at the specified location from the receiver’s internal item list.
- (void)removeItemAtIndex:(NSInteger)index
The index of the object to remove from the receiver's internal item list. All items beyond index are moved up one slot to fill the gap.
The removed object receives a release
message. This method raises an NSRangeException
if index is beyond the end of the list and logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Removes all occurrences of the specified object from the receiver’s internal item list.
- (void)removeItemWithObjectValue:(id)anObject
The object to remove from the receiver's internal item list. Objects are considered equal if they have the same id or if isEqual:
returns YES
.
This method logs a warning if usesDataSource
returns YES
.
NSComboBoxCell.h
Scrolls the receiver’s pop-up list vertically so that the item at the given index is as close to the top as possible.
- (void)scrollItemAtIndexToTop:(NSInteger)index
The index of the item to scroll to the top.
The pop-up list need not be displayed at the time this method is invoked.
NSComboBoxCell.h
Scrolls the receiver’s pop-up list vertically so that the item at the given index is visible.
- (void)scrollItemAtIndexToVisible:(NSInteger)index
The index of the item to make visible.
The pop-up list need not be displayed at the time this method is invoked.
NSComboBoxCell.h
Selects the pop-up list row at the given index.
- (void)selectItemAtIndex:(NSInteger)index
The index of the row to select.
Posts an NSComboBoxSelectionDidChangeNotification
to the default notification center if the selection does in fact change. Note that this method does not alter the contents of the combo box cell’s text field—see “Setting the Combo Box’s Value” for more information.
– setObjectValue:
(NSControl)NSComboBoxCell.h
Selects the first pop-up list item that corresponds to the specified object.
- (void)selectItemWithObjectValue:(id)anObject
The object for which to select the corresponding pop-up list item. Objects are considered equal if they have the same id or if isEqual:
returns YES
.
This method logs a warning if usesDataSource
returns YES
. Posts an NSComboBoxSelectionDidChangeNotification
to the default notification center if the selection does in fact change. Note that this method doesn’t alter the contents of the combo box cell’s text field—see “Setting the Combo Box’s Value” for more information.
– setObjectValue:
(NSControl)NSComboBoxCell.h
Determines whether the button in the combo box is displayed with a border.
- (void)setButtonBordered:(BOOL)flag
YES
to display a border. For example, it is often useful when using a combo box in an NSTableView
to display the button without the border.
NSComboBoxCell.h
Sets whether the receiver tries to complete what the user types in the text field.
- (void)setCompletes:(BOOL)completes
YES
to indicate that the receiver should try to complete text typed by the user. If completes is YES
, every time the user adds characters to the end of the text field, the combo box calls the NSComboBoxCell method completedString:
.
If completedString:
returns a string that’s longer than the existing string, the combo box replaces the existing string with the returned string and selects the additional characters. If the user is deleting characters or adds characters somewhere besides the end of the string, the combo box does not try to complete it.
NSComboBoxCell.h
Sets the receiver’s data source.
- (void)setDataSource:(id)aSource
The data source for the receiver. aSource should implement the appropriate methods of the NSComboBoxCellDataSource informal protocol.
This method logs a warning if aSource doesn’t respond to either numberOfItemsInComboBoxCell:
or comboBoxCell:objectValueForItemAtIndex:
.
This method doesn’t automatically set usesDataSource
to NO
and in fact logs a warning if usesDataSource
returns NO
.
NSComboBoxCell.h
Determines whether the receiver displays a vertical scroller.
- (void)setHasVerticalScroller:(BOOL)flag
YES
to have the receiver display a vertical scroller. By default, flag is YES
.
If flag is NO
and the combo box cell has more list items (either in its internal item list or from its data source) than are allowed by numberOfVisibleItems
, only a subset will be displayed. NSComboBoxCell’s scroll...
methods can be used to position this subset within the pop-up list.
Note that if flag is YES
, a scroller will be displayed even if the combo box cell has fewer list items than are allowed by numberOfVisibleItems
.
NSComboBoxCell.h
Sets the spacing between pop-up list items.
- (void)setIntercellSpacing:(NSSize)aSize
The width and height between pop-up list items. The default intercell spacing is (3.0, 2.0).
NSComboBoxCell.h
Sets the height for items.
- (void)setItemHeight:(CGFloat)itemHeight
The height of pop-up list items.
NSComboBoxCell.h
Sets the maximum number of items that are visible in the pop-up list.
- (void)setNumberOfVisibleItems:(NSInteger)visibleItems
The maximum number of items that should be visible at one time in the receiver's pop-up list.
NSComboBoxCell.h
Sets whether the receiver uses an external data source to populate its pop-up list.
- (void)setUsesDataSource:(BOOL)flag
YES
to indicate that the receiver uses an external data source (specified by setDataSource:
) to populate the receiver’s pop-up list.
NSComboBoxCell.h
Returns a Boolean value indicating whether the receiver uses an external data source.
- (BOOL)usesDataSource
YES
if the receiver uses an external data source to populate the receiver’s pop-up list, NO
if it uses an internal item list.
NSComboBoxCell.h
© 2006 Apple Computer, Inc. All Rights Reserved. (Last updated: 2006-05-23)