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
* 
	 * @return <code>true</code> if color icons should be used in toolbars,
	 *         <code>false</code> otherwise
	 */
	public static boolean getUseColorIconsInToolbars() {
		return USE_COLOR_ICONS;
	}
	/**
	 * Sets whether color icons should be used in toolbars.
	 * 
	 * @param useColorIcons
	 *            <code>true</code> if color icons should be used in toolbars,
	 *            <code>false</code> otherwise
	 */
	public static void setUseColorIconsInToolbars(boolean useColorIcons) {
		USE_COLOR_ICONS = useColorIcons;
	}
	/**
	 * The presentation mode.
	 */
	private int mode = 0;
	/**
	 * The action.
	 */
	private IAction action;
	/**
	 * The listener for changes to the text of the action contributed by an
	 * external source.
	 */
	private final IPropertyChangeListener actionTextListener = new IPropertyChangeListener() {