@Override
 public boolean close() {
   if (mSection != null) {
     INIFile iniFile = (INIFile) mSection.getParent();
     if (iniFile != null) {
       iniFile.setValidateFixMode(mOldValidateFixMode);
     }
   }
   if (mCurrentWidget != null) {
     mCurrentWidget.removeModelCommandListener(InstallOptionsWidgetEditorDialog.this);
     mCurrentWidget.removePropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
     if (mCurrentWidget.getParent() != null) {
       mCurrentWidget
           .getParent()
           .removePropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
     }
   }
   return super.close();
 }
 @Override
 protected void okPressed() {
   if (mDialog.canUpdateINIFile()) {
     mDialog.updateINIFile();
     if (mSection == null) {
       mSection = mCurrentWidget.getSection();
     }
     super.okPressed();
   } else {
     super.cancelPressed();
   }
 }
 public void propertyChange(PropertyChangeEvent evt) {
   if (evt.getPropertyName().equals(InstallOptionsModel.PROPERTY_INDEX)) {
     mDialog.moveChild(mCurrentWidget, ((Integer) evt.getNewValue()).intValue());
   } else if (evt.getPropertyName().equals(InstallOptionsModel.PROPERTY_CHILDREN)) {
     if (Common.objectsAreEqual(mCurrentWidget, evt.getOldValue())
         && evt.getNewValue() instanceof InstallOptionsWidget) {
       InstallOptionsWidget widget = (InstallOptionsWidget) evt.getNewValue();
       mCurrentWidget.removeModelCommandListener(InstallOptionsWidgetEditorDialog.this);
       mCurrentWidget.removePropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
       mCurrentWidget = widget;
       mSection = mCurrentWidget.getSection();
       mCurrentWidget.addModelCommandListener(InstallOptionsWidgetEditorDialog.this);
       mCurrentWidget.addPropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
       Display.getDefault()
           .asyncExec(
               new Runnable() {
                 public void run() {
                   mPage.selectionChanged(null, new StructuredSelection(mCurrentWidget));
                 }
               });
     }
   }
 }
  @Override
  protected Control createControl(Composite parent) {
    Composite propertyComposite = new Composite(parent, SWT.BORDER);
    GridLayout layout = new GridLayout(1, false);
    layout.marginWidth = layout.marginHeight = 0;
    propertyComposite.setLayout(layout);
    if (mPage instanceof Page) {
      ((Page) mPage)
          .init(
              new IPageSite() {
                public void registerContextMenu(
                    String menuId, MenuManager menuManager, ISelectionProvider selectionProvider) {}

                public IActionBars getActionBars() {
                  return null;
                }

                public IWorkbenchPage getPage() {
                  return getWorkbenchWindow().getActivePage();
                }

                public ISelectionProvider getSelectionProvider() {
                  return null;
                }

                public Shell getShell() {
                  return getWorkbenchWindow().getShell();
                }

                public IWorkbenchWindow getWorkbenchWindow() {
                  return PlatformUI.getWorkbench().getActiveWorkbenchWindow();
                }

                public void setSelectionProvider(ISelectionProvider provider) {}

                @SuppressWarnings("unchecked")
                public Object getAdapter(Class adapter) {
                  return null;
                }

                @SuppressWarnings("unchecked")
                public Object getService(Class api) {
                  return null;
                }

                @SuppressWarnings("unchecked")
                public boolean hasService(Class api) {
                  return false;
                }
              });
    }
    if (mPage instanceof PropertySheetPage) {
      ((PropertySheetPage) mPage).setPropertySourceProvider(this);
    }
    mPage.createControl(propertyComposite);
    mPage.setActionBars(new DummyActionBars());
    final Control control = mPage.getControl();
    GridData data = new GridData(SWT.FILL, SWT.FILL, true, true);
    if (control instanceof Tree) {
      final Tree tree = (Tree) control;
      data.heightHint =
          tree.getItemHeight() * 13
              + (tree.getLinesVisible() ? 12 * tree.getGridLineWidth() : 0)
              + (tree.getHeaderVisible() ? tree.getHeaderHeight() : 0)
              + 2 * tree.getBorderWidth()
              + (tree.getHorizontalBar() != null ? tree.getHorizontalBar().getSize().x : 0);
      tree.addControlListener(
          new ControlAdapter() {
            @Override
            public void controlResized(ControlEvent e) {
              Rectangle area = tree.getClientArea();
              TreeColumn[] columns = tree.getColumns();
              if (area.width > 0) {
                columns[0].setWidth(area.width * 40 / 100);
                columns[1].setWidth(area.width - columns[0].getWidth() - 4);
              }
            }
          });
    } else if (control instanceof Composite) {
      control.addControlListener(
          new ControlAdapter() {
            @Override
            public void controlResized(ControlEvent e) {
              ((Composite) control).layout(true, true);
            }
          });
    }
    control.setLayoutData(data);
    ISelection selection;
    if (mCurrentWidget == null) {
      Collection<InstallOptionsModelTypeDef> typeDefs =
          InstallOptionsModel.INSTANCE.getControlTypeDefs();
      if (typeDefs.size() > 0) {
        InstallOptionsModelTypeDef typeDef = typeDefs.iterator().next();
        InstallOptionsElementFactory factory =
            InstallOptionsElementFactory.getFactory(typeDef.getType());
        mCurrentWidget = (InstallOptionsWidget) factory.getNewObject();
        mDialog.addChild(mCurrentWidget);
      }
    }

    if (mCurrentWidget != null) {
      mCurrentWidget.addModelCommandListener(InstallOptionsWidgetEditorDialog.this);
      mCurrentWidget.addPropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
      if (mCurrentWidget.getParent() != null) {
        mCurrentWidget.getParent().addPropertyChangeListener(InstallOptionsWidgetEditorDialog.this);
      }
      selection = new StructuredSelection(mCurrentWidget);
    } else {
      selection = StructuredSelection.EMPTY;
    }

    mPage.selectionChanged(null, selection);
    PlatformUI.getWorkbench().getHelpSystem().setHelp(mPage.getControl(), HELP_CONTEXT);
    PlatformUI.getWorkbench().getHelpSystem().setHelp(propertyComposite, HELP_CONTEXT);

    return propertyComposite;
  }