Today we can not think an application without Ajax/js. Good news APEX already included external js/css facility. First time i have faced some problem implemented external js in APEX but finally implemented. Now step by step we will show the process…
1. Open your application and click ‘Shared components’.
2. At the bottom of the page ‘Files’ block, click ‘Static files’
3. Click ‘Create’ button from top right corner. Browse your js file i.e.jquery.js
5. Now call your js functions & enJoy!
Best of luck , if further any query please buzz me.