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
* <code>MODE_*</code> constants.
	 * 
	 * @param mode
	 *            the presentation mode settings
	 * 
	 * @since 3.0
	 */
	public void setMode(int mode) {
		this.mode = mode;
		update();
	}
	/**
	 * The action item implementation of this <code>IContributionItem</code>
	 * method calls <code>update(null)</code>.
	 */
	public final void update() {
		update(null);
	}
	/**
	 * Synchronizes the UI with the given property.
	 * 
	 * @param propertyName
	 *            the name of the property, or <code>null</code> meaning all
	 *            applicable properties
	 */
	public void update(String propertyName) {
		if (widget != null) {
			
			boolean textChanged = propertyName == null
					|| propertyName.equals(IAction.TEXT);