Bug 161805 [Viewers] JFace TreeViewer collapses node when sibbling removed
3.2 1. Use the Eclipse Wizard to produce a plugin with a tree viewer view. 2. Paste the modified SampleView.java - this looks like the left part of the attached screenshot 3. Click on the top node Parent1 and type - 4. TreeViewer.remove is called to remove Parent 1. TreeViewer.refresh is called - this looks like the right part of the attached screenshot Wrong: node Parent 4 is now collapsed. Expectation Parent 4 is still expanded. Is there any workaround? Am I misusing your API? Note. The snippet is almost identical to the code generated by PDE for plugin / view / Tree Viewer. Here is the extra code in createPartControl: viewer.getTree().addKeyListener(new KeyListener() { public void keyReleased(KeyEvent e) { // TODO Auto-generated method stub } public void keyPressed(KeyEvent e) { if (e.character == '-') { TreeParent parent = (TreeParent) ((IStructuredSelection)viewer.getSelection()).toArray()[0]; parent.getParent().removeChild(parent); viewer.refresh(); } if (e.character == '+') { TreeParent parent = (TreeParent) ((IStructuredSelection)viewer.getSelection()).toArray()[0]; parent.addChild(new TreeParent(new Date().toString())); } } });
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
public void setContentProvider(IContentProvider provider) {
		
		super.setContentProvider(provider);
	}
	protected void assertContentProviderType(IContentProvider provider) {
		Assert.isTrue(provider instanceof ITreeContentProvider
				|| provider instanceof ITreePathContentProvider);
	}
	/**
	 * Sets the expand state of the given item.
	 * 
	 * @param item
	 *            the item
	 * @param expand
	 *            the expand state of the item
	 */
	protected abstract void setExpanded(Item item, boolean expand);
	/**
	 * Sets which nodes are expanded in this viewer's tree. The given list
	 * contains the elements that are to be expanded; all other nodes are to be
	 * collapsed.
	 * <p>
	 * This method is typically used when restoring the interesting state of a
	 * viewer captured by an earlier call to <code>getExpandedElements</code>.
	 * </p>
	 * 
	 * @param elements
	 *            the array of expanded elements
	 * @see #getExpandedElements
	 */