I have created a custom widget in gwt which extends the composite.I am using focus panel in that.For FocusPanel I added ClickHandler.Then I have added keyboard listner.Now o
You can also use a simple JSNI method to do it. Just pass your element [e.g. button.getElement()] to this method:
public static native void clickElement(Element elem) /*-{ elem.click(); }-*/;