How to write java script in Resco Mobile CRM Environment OnChange,OnSave,OnLoad Events?

Hi, 

I am new to Resco,

Any one please let me know the steps to write javascript in Resco MobileCRM on the OnChange, OnSave, OnLoad Events.

I want to update one field with time only and one field with the auto generate number when the form is saving.

please help me.

Thanks.