Bug 38477 add delegate methods: OK enabled even if nothing selected
20030604 the OK button is enabled even if nothing is selected in the dialog
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/actions/AddDelegateMethodsAction.java
return null;
					}
					res[i] = fld;
				} else {
					return null;
				}
			}
			return res;
		}
		return null;
	}
	private void run(IType type, IField[] preselected, boolean editor) throws CoreException {
		if (!ElementValidator.check(type, getShell(), DIALOG_TITLE, editor))
			return;
		if (!ActionUtil.isProcessable(getShell(), type))
			return;
		if(!canEnableOn(type)){
			MessageDialog.openInformation(getShell(), DIALOG_TITLE, ActionMessages.getString("AddDelegateMethodsAction.not_applicable")); 
			return;
		}			
		showUI(type, preselected);
	}
	
	/* (non-Javadoc)
	 * Method declared on SelectionDispatchAction
	 */
	public void selectionChanged(ITextSelection selection) {
	}
	/* (non-Javadoc)
	 * Method declared on SelectionDispatchAction