This is an example of how to create a MenuBar using the Google Web Toolkit, that is an open source set of tools that allows web developers to create and maintain complex JavaScript front-end applications in Java. Creating a MenuBar implies that you should:
- The
MenuExampleclass implements thecom.google.gwt.core.client.EntryPointinterface to allow the class to act as a module entry point. It overrides itsonModuleLoad()method. It also implements thecom.google.gwt.user.client.Commandso that it can have a Command associated with it that it executes when it is chosen by the user. - Create a new Instance of MenuBar.
- Create sub- MenuBar items and add Items to them.
- Add the sub- MenuBar items to the MenuBar.
- Add the MenuBarto the
RootPanel, that is the panel to which all other widgets must ultimately be added.
Let’s take a look at the code snippet that follows:
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 | package com.javacodegeeks.snippets.enterprise;import com.google.gwt.user.client.Command;import com.google.gwt.core.client.EntryPoint;import com.google.gwt.user.client.ui.RootPanel;import com.google.gwt.user.client.ui.MenuBar;import com.google.gwt.user.client.ui.MenuItem;public class MenuExample implements EntryPoint, Command { @Override public void onModuleLoad() { //Create new Instance of MenuBar MenuBar menu = new MenuBar(); menu.setAutoOpen(true); //Set subMenu Items for Item 2 of Menu0 MenuBar subMenu = new MenuBar(true); subMenu.addItem("Item 0,2,0", true, this); subMenu.addItem("Item 0,2,1", true, this); subMenu.addItem("Item 0,2,2", true, this); //Set Menu0 Items MenuBar menu0 = new MenuBar(true); menu0.addItem("Item 0,0", true, this); menu0.addItem("Item 0,1", true, this); menu0.addItem("Item 0,2", true, subMenu); //Set Menu1 Items MenuBar menu1 = new MenuBar(true); menu1.addItem("Item 1,0", true, this); menu1.addItem("Item 1,1", true, this); menu1.addItem("Item 1,2", true, this); //Set Menu2 Items MenuBar menu2 = new MenuBar(true); menu2.addItem("Item 2,0", this); menu2.addItem("Item 2,1", this); menu2.addItem("Item 2,2", true, this); //Add Menu Items to Menu menu.addItem(new MenuItem("Menu 0", menu0)); menu.addItem(new MenuItem("Menu 1", menu1)); menu.addItem(new MenuItem("Menu 2", menu2)); menu.setWidth("100%"); //Add Menu to Root Panel RootPanel.get().add(menu); } @Override public void execute() { return; } } |
This was an example of how to create a MenuBar with the Google Web Toolkit.
