How to get the widget's parent Object?

[jyotisaxena]

Hi,
I need to fetch the parent for a particular swt.widget object. I know of two methods: WidgetLocatorService.getParent and SWTHierarchyHelper(Display).getParent. Both seem to belong to restricted access. Is there a better way?

[Phil Quitslund]

Hmmmm.... Ideally, our locators should protect you from needing to traverse the widget graph yourself. What are you trying to do? Why do you need access to the parent?

[jyotisaxena]

Some of our widgets are not directly labelled, they are encapsulated. Like ComboBox, it is a childWidget of our specified AxCombo type. I have overridden the matcher function where i traverse through the hierarchy, find the immediate sibling label of AxCombo matching the specified widget label. Similarly We have our own matchers for links and text fields too due to encapsulation.

[Phil Quitslund]

Interesting. Thanks for the context. I would recommend maintaining your own version of such a utility method. Here's some code to get you started. (Note: this could be cleaned up and optimized but you get the idea!)

Code: Select all

// Copyright 2010 Google Inc. All Rights Reserved.

import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DropTarget;
import org.eclipse.swt.widgets.Caret;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.CoolItem;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;
import org.eclipse.swt.widgets.ScrollBar;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TabItem;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.ToolItem;
import org.eclipse.swt.widgets.Tracker;
import org.eclipse.swt.widgets.TreeItem;
import org.eclipse.swt.widgets.Widget;



public class WidgetUtils {

  public synchronized Widget getParent(final Widget widget) {

    if (widget instanceof Shell)
      return null; //this preserves some WT finder behavior but may not be what you want...

    if (widget == null || widget.isDisposed())
      return null;

    final Widget[] parent = new Widget[1];

    widget.getDisplay().syncExec(new Runnable() {
      public void run() {
        if (widget instanceof Control)
          parent[0] = ((Control) widget).getParent();
        if (widget instanceof Caret)
          parent[0] = ((Caret) widget).getParent();
        if (widget instanceof Menu)
          parent[0] = ((Menu) widget).getParent();
        if (widget instanceof ScrollBar)
          parent[0] = ((ScrollBar) widget).getParent();
        if (widget instanceof CoolItem)
          parent[0] = ((CoolItem) widget).getParent();
        if (widget instanceof MenuItem)
          parent[0] = ((MenuItem) widget).getParent();
        if (widget instanceof TabItem)
          parent[0] = ((TabItem) widget).getParent();
        if (widget instanceof TableColumn)
          parent[0] = ((TableColumn) widget).getParent();
        if (widget instanceof TableItem)
          parent[0] = ((TableItem) widget).getParent();
        if (widget instanceof ToolItem)
          parent[0] = ((ToolItem) widget).getParent();
        if (widget instanceof TreeItem)
          parent[0] = ((TreeItem) widget).getParent();
        if (widget instanceof DragSource)
          parent[0] = ((DragSource) widget).getControl().getParent();
        if (widget instanceof DropTarget)
          parent[0] = ((DropTarget) widget).getControl().getParent();
        if (widget instanceof Tracker)
          debug("requested the parent of a Tracker- UNFINDABLE");
      }
    });
    return parent[0];
  }

  private static void debug(String msg) {
    System.out.println(msg);
  }

}


Hope this helps!

[jyotisaxena]

Yes, it very much helped. Thanks very much. Happy thanksgiving.

[keertip]

Good to know that worked.