what wrong in my zkoss code

I am getting the key press of each word and I need to make an autosuggest in a combobox. My code is the following:

<zk>
    <window border="normal" appl开发者_StackOverflowy="org.test.test" id="win" >
    <combobox id="combo" autodrop="true"/>
    </window>
</zk>

The GenericForwardComposer:

public class test extends GenericForwardComposer{
   Combobox combo; //ZK Auto Wired , use combo directly

   public void onChanging$combo() { // ZK Autoforward (Awesome !!)
     suggest();
   }

   public void suggest() {   
     System.out.println(combo.getText());
     combo.getItems().clear();
     combo.appendItem("Ace");
     combo.appendItem("Ajax");
     combo.appendItem("Apple");
     combo.appendItem("Best");
     combo.appendItem("Blog");
   }

 }

This is not printing the first key when I press a key. Can I please get some help to know why????

---

When onChanging is received, the value of combobox is not changed yet. You have to get the value from the event

public void onChanging$como(InputEvent event) {
    event.getValue(); //<- the value of combobox being entered so far