Package org.eclipse.jface.viewers

Class TreeNodeContentProvider

java.lang.Object

org.eclipse.jface.viewers.TreeNodeContentProvider

All Implemented Interfaces:

IContentProvider, IStructuredContentProvider, ITreeContentProvider

public class TreeNodeContentProvider
extends Object
implements ITreeContentProvider

A content provider that expects every element to be a TreeNode. Most methods delegate to TreeNode. dispose() and inputChanged(Viewer, Object, Object) do nothing by default.

This class and all of its methods may be overridden or extended.

Since:

3.2

See Also:

TreeNode

Constructor Summary

Constructors

Constructor	Description
TreeNodeContentProvider()

Method Summary

Modifier and Type	Method	Description
Object[]	getChildren(Object parentElement)	Returns the child elements of the given parent element.
Object[]	getElements(Object inputElement)	Returns the elements to display in the viewer when its input is set to the given element.
Object	getParent(Object element)	Returns the parent for the given element, or null indicating that the parent can't be computed.
boolean	hasChildren(Object element)	Returns whether the given element has children.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.eclipse.jface.viewers.IContentProvider

dispose, inputChanged

Constructor Detail

TreeNodeContentProvider

public TreeNodeContentProvider()

Method Detail

getChildren

public Object[] getChildren(Object parentElement)

Description copied from interface: ITreeContentProvider

Returns the child elements of the given parent element.

The difference between this method and IStructuredContentProvider.getElements is that getElements is called to obtain the tree viewer's root elements, whereas getChildren is used to obtain the children of a given parent element in the tree (including a root).

The result is not modified by the viewer.

Specified by:

getChildren in interface ITreeContentProvider

Parameters:

parentElement - the parent element

Returns:

an array of child elements

getElements

public Object[] getElements(Object inputElement)

Description copied from interface: ITreeContentProvider

Returns the elements to display in the viewer when its input is set to the given element. These elements can be presented as rows in a table, items in a list, etc. The result is not modified by the viewer.

NOTE: The returned array must not contain the given inputElement, since this leads to recursion issues in AbstractTreeViewer (see bug 9262).

Specified by:

getElements in interface IStructuredContentProvider

Specified by:

getElements in interface ITreeContentProvider

Parameters:

inputElement - the input element

Returns:

the array of elements to display in the viewer

getParent

public Object getParent(Object element)

Description copied from interface: ITreeContentProvider

Returns the parent for the given element, or null indicating that the parent can't be computed. In this case the tree-structured viewer can't expand a given node correctly if requested.

Specified by:

getParent in interface ITreeContentProvider

Parameters:

element - the element

Returns:

the parent element, or null if it has none or if the parent cannot be computed

hasChildren

public boolean hasChildren(Object element)

Description copied from interface: ITreeContentProvider

Returns whether the given element has children.

Intended as an optimization for when the viewer does not need the actual children. Clients may be able to implement this more efficiently than getChildren.

Specified by:

hasChildren in interface ITreeContentProvider

Parameters:

element - the element

Returns:

true if the given element has children, and false if it has no children