Bug 36446 [Contributions] widgets: Associating Actions with Buttons
Actions can be associated with Menu items , and tool bar items using MenuManager and ToolBarManager but there is not way to associate Action with a regular button and obtaining a reference to that button the closest thing is creating an ActionContributionItem with the desired action in its constructor , then filling the parent composite with ActionContributionItem.fill(Control parent) this creats the button , but it doesn't return a reference to that button , so for example i can't give it any layout data i suggest the ActionContributionItem.fill(Control parent) returns the created widget
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ActionContributionItem.java
case SWT.Selection:
						Widget ew = event.widget;
						if (ew != null) {
							handleWidgetSelection(event, ((Button) ew)
									.getSelection());
						}
						break;
					}
				}
			};
		}
		return buttonListener;
	}
	/**
	 * Returns the listener for SWT menu item widget events.
	 * 
	 * @return a listener for menu item events
	 */
	private Listener getMenuItemListener() {
		if (menuItemListener == null) {
			menuItemListener = new Listener() {
				public void handleEvent(Event event) {
					switch (event.type) {
					case SWT.Dispose:
						handleWidgetDispose(event);
						break;
					case SWT.Selection:
						Widget ew = event.widget;
						if (ew != null) {
							handleWidgetSelection(event, ((MenuItem) ew)