Interaction between flex and JS

Flex interacts with JavaScript, mainly relying on the flex externalinterface, which provides addcallback and call methods.

The following example demonstrates how Flex calls JavaScript and JavaScript calls flex.

JS Code

2. FunctionHello (PARAM ){
   
4. Alert (PARAM );
6. Return
   "JSP Hello :"+ Param;
8. }
12. FunctionCallflexfunction (){
    
14. VaRX = Document. getelementbyid ("Flexobject"). Flexhelloworld ("Hello",
    "World");
16. Alert (X );
18. }

Flex code

2. <?XML
   Version="1.0"
   Encoding="UTF-8"?> 
   
4. <MX: Application
   Xmlns: MX=Http://www.adobe.com/2006/mxml"
   Layout="Absolute" 
   
6. Initialize="Initapp ()"> 
   
10. <MX: script> 
    
12. <! [CDATA
14. Import MX. Controls. Alert;
18. Public Function flexhelloworld (param1: String, param2: string): String {
    
20. Alert. Show ("param1:" + param1 + "; param2:" + param2 );
    
22. Return "hello" + param1 + param2;
24. }
28. Public Function initapp (): void {
30. Externalinterface. addcallback ("flexhelloworld", flexhelloworld );
    
32. }
36. Public Function jsphello (): void {
38. VaRS: String=
    Externalinterface. Call ("hello", "flex ");
    
40. Alert. Show (s );
42. }
46. ]>
48. </MX: script> 
    
52. <MX: button
    X="52"
    Y="58"
    Label="Call JavaScript"
    Click="Jsphello ()"/> 
    
56. mx: application