LWUIT 1.5 How to capture tab click event, fetch content from server and show it in selected tab?

Question

I am using LWUIT 1.5 tabs to show notifications. I have three Tabs and I fetch notifications from a php web service. I successfully fetched list of notifications for first Tab. But for next two Tabs I am failing to understand what code I should write to

1. Detect that second/third Tab is clicked. I know how to add commandListener to a Button. What commandListener is there for Tab selection?

2. How to refresh content of a Tab when new data is received from the server?

   private void showNotificationList() {

   try {
   
       Form f = new Form("Notifications");
       f.setScrollable(false);
       f.setLayout(new BorderLayout());
       final List list = new List(getNotifications()); //gets hashtables - notices
       list.setRenderer(new GenericListCellRenderer(createGenericRendererContainer(), createGenericRendererContainer()));
       list.setSmoothScrolling(true);
       //System.out.println("adding list component to listview");
       list.addActionListener(new ActionListener() {
   
           public void actionPerformed(ActionEvent evt) {
               int i = list.getSelectedIndex();
               noticeDetailsForm(notices[i]);
               //Dialog. show( "title",  notices[i].toString(),  "ok",  "exitt");
           }
       });
       //Container c2 = new Container(new BoxLayout(BoxLayout.Y_AXIS));
       //c2.addComponent(list);
       Tabs tabs = new Tabs(Tabs.TOP);
       tabs.addTab("Recent", list);
       tabs.addTab("Urgent", new Label("urgent goes here"));
       tabs.addTab("Favourites", new Label("favs goes here"));
   
       //f.addComponent(tabs);
       f.addComponent(BorderLayout.CENTER, tabs);
       Command backComm = new Command("Back") {
   
           public void actionPerformed(ActionEvent ev) {
               Dashboard.dbInstance.setUpDashboard();
   
           }
       };
       f.addCommand(backComm);
       //System.out.println("showing lsit form");
       f.show();
   } catch (Exception ex) {
       ex.printStackTrace();
   }
   

   }

   private Container createGenericRendererContainer() throws IOException { //System.out.println("container called");
   
   //System.out.println("container called");
   Container c = new Container(new BorderLayout());
   c.setUIID("ListRenderer");
   
   Label xname = new Label("");
   Label description = new Label();
   Label focus = new Label("");
   Container cnt = new Container(new BoxLayout(BoxLayout.Y_AXIS));
   xname.setName("Name");
   xname.getStyle().setBgTransparency(0);
   xname.getStyle().setFont(Font.createSystemFont(Font.FACE_SYSTEM, Font.STYLE_BOLD, Font.SIZE_MEDIUM));
   //description.setFocusable(true);
   description.setName("Description");
   cnt.addComponent(xname);
   cnt.addComponent(description);
   c.addComponent(BorderLayout.CENTER, cnt);
   Button thumb = new Button(Image.createImage("/res/home-work.png"));
   //Image img = Image.createImage("/res/home-work.png");
   c.addComponent(BorderLayout.WEST, thumb);
   
   return c;
   

   }

   private Hashtable[] getNotifications() { int total = notices.length; //System.out.println(total); Hashtable[] data = new Hashtable[total]; //Hashtable[] data = new Hashtable[5]; /data[0] = new Hashtable(); data[0].put("Name", "Shai"); data[0].put("Surname", "Almog"); data[0].put("Selected", Boolean.TRUE);/

   for (int i = 0; i < total; i++) {
       data[i] = new Hashtable();
       //System.out.println(notices[i].getName());
       data[i].put("Name", notices[i].getName());
       data[i].put("Description", notices[i].getDescription());
       data[i].put("Id", Integer.toString(notices[i].getId()));
   }
   
   return data;
   

   }

Answer 1

1)I had the same problem and I solved it by overriding Keyreleased of the Form not the Tab and inside it I check for the component that is focused and if it is the Tab get "tab.selectedIndex" to detect in which Tab I am and load appropriate data . Here is Sample code(this inside the my derived form that extends Form )

**

public void keyReleased(int keyCode) {
        Component p=this.getFocused();
       String str= p.getClass().getName();
    if(str.toLowerCase().indexOf("radiobutton")!=-1){    // Radiobutton because when u 
  Here do tab specific work                              focus on the 
                                                         tab it returns radiobutton.                                    
                                                         lwuit understands tabs as list   
                                                         of radiobuttons 
                      }**

2)and about refreshing the data I did a solution and I don't Know if its right I get the new data , create new List and remove the old one and attach the new one then call Form.repaint();