Eclipse Platform
2.0

org.eclipse.ui.model
Class WorkbenchContentProvider

java.lang.Object
  |
  +--org.eclipse.ui.model.WorkbenchContentProvider
All Implemented Interfaces:
EventListener, IContentProvider, IResourceChangeListener, IStructuredContentProvider, ITreeContentProvider

public class WorkbenchContentProvider
extends Object
implements ITreeContentProvider, IResourceChangeListener

Provides tree contents for objects that have the IWorkbenchAdapter adapter registered.


Field Summary
protected  Viewer viewer
           
 
Constructor Summary
WorkbenchContentProvider()
           
 
Method Summary
 void dispose()
          Disposes of this content provider.
protected  IWorkbenchAdapter getAdapter(Object o)
          Returns the implementation of IWorkbenchAdapter for the given object.
 Object[] getChildren(Object element)
          Returns the child elements of the given parent element.
 Object[] getElements(Object element)
          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.
 void inputChanged(Viewer viewer, Object oldInput, Object newInput)
          Notifies this content provider that the given viewer's input has been switched to a different element.
protected  void processDelta(IResourceDelta delta)
          Process a resource delta.
 void resourceChanged(IResourceChangeEvent event)
          The workbench has changed.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

viewer

protected Viewer viewer
Constructor Detail

WorkbenchContentProvider

public WorkbenchContentProvider()
Method Detail

dispose

public void dispose()
Description copied from interface: IContentProvider
Disposes of this content provider. This is called by the viewer when it is disposed.

The viewer should not updated during this call, as it is in the process of being disposed.

Specified by:
dispose in interface IContentProvider

getAdapter

protected IWorkbenchAdapter getAdapter(Object o)
Returns the implementation of IWorkbenchAdapter for the given object. Returns null if the adapter is not defined or the object is not adaptable.


getChildren

public Object[] getChildren(Object element)
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:
element - the parent element
Returns:
an array of child elements

getElements

public Object[] getElements(Object element)
Description copied from interface: IStructuredContentProvider
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.

Specified by:
getElements in interface IStructuredContentProvider
Parameters:
element - 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

inputChanged

public void inputChanged(Viewer viewer,
                         Object oldInput,
                         Object newInput)
Description copied from interface: IContentProvider
Notifies this content provider that the given viewer's input has been switched to a different element.

A typical use for this method is registering the content provider as a listener to changes on the new input (using model-specific means), and deregistering the viewer from the old input. In response to these change notifications, the content provider should update the viewer (see the add, remove, update and refresh methods on the viewers).

The viewer should not updated during this call, as it might be in the process of being disposed.

Specified by:
inputChanged in interface IContentProvider
Parameters:
viewer - the viewer
oldInput - the old input element, or null if the viewer did not previously have an input
newInput - the new input element, or null if the viewer does not have an input

processDelta

protected void processDelta(IResourceDelta delta)
Process a resource delta.


resourceChanged

public void resourceChanged(IResourceChangeEvent event)
The workbench has changed. Process the delta and issue updates to the viewer, inside the UI thread.

Specified by:
resourceChanged in interface IResourceChangeListener
Parameters:
event - the resource change event
See Also:
IResourceChangeListener.resourceChanged(org.eclipse.core.resources.IResourceChangeEvent)

Eclipse Platform
2.0

Copyright (c) IBM Corp. and others 2000, 2002. All Rights Reserved.