A context menu appears when the user right-clicks some component. Vaadin supports context menus for Table, Tree, and TreeTable. Menu options are encapsulated using Action instances:
final Action action = new Action("Say hello");To add actions and respond to them, we must add a Handler. A Handler is an interface with two methods:
public interface Handler extends Serializable { public Action[] getActions(Object target, Object sender); public void handleAction(Action action, Object sender, Object target); }
getActions must return an array containing all the actions we want to show in our context menu. handleAction will be called when an action is performed (the user clicks a menu item). Here is an example implementation that shows a somewhat uncouth salutation:
table.addActionHandler(new Handler() {
public void handleAction(Action action, Object sender,
Object target) {
Notification.show("Ok, here I go... Hello.");
}
public Action[] getActions(Object...