CH03.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
              xmlns:s="library://ns.adobe.com/flex/spark" 
              xmlns:mx="library://ns.adobe.com/flex/mx">
       
  <fx:Script>
    <![CDATA[
     import mx.controls.Alert;      
     public function checkPassword():void
     {
        if(password.text.length < 1)                                  
          Alert.show("Missing Password!");                
        else                                                          
          Alert.show("Looks Good!");    
     }
    ]]>
  </fx:Script>
  <s:Group>
    <s:layout>
      <s:VerticalLayout/>
    </s:layout>
    <s:TextInput id="password"/>
    <s:Button label="Check Password" click="checkPassword()"/>    
  </s:Group>
</s:Application>