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
}
			}
			
			action.removePropertyChangeListener(propertyListener);
			if (action != null) {
				String commandId = action.getActionDefinitionId();
				ExternalActionManager.ICallback callback = ExternalActionManager
						.getInstance().getCallback();
				if ((callback != null) && (commandId != null)) {
					callback.removePropertyChangeListener(commandId,
							actionTextListener);
				}
			}
			
			widget = null;
			disposeOldImages();
		}
	}
	/**
	 * Handles a widget selection event.
	 */
	private void handleWidgetSelection(Event e, boolean selection) {
		Widget item = e.widget;
		if (item != null) {
			int style = item.getStyle();
			if ((style & (SWT.TOGGLE | SWT.CHECK)) != 0) {
				if (action.getStyle() == IAction.AS_CHECK_BOX) {
					action.setChecked(selection);
				}
			} else if ((style & SWT.RADIO) != 0) {