Flash programming language(AS3) is similar to Java. So once you get familiar with Flash Pro IDE you should get going easily. So before proceeding any further I will suggest you to read followings:
This should get you started, then move on to following and explore in detail as and when you have time:
To answer your query you can edit the source by using Action Script editor which can be directly opened by pressing F9. Action Script code can also be directly written to seperate .as file instead of .fla in which case you open the .as file if the editor panel is not open press F9.
Thank you for your reponse.
I would like to put here that if you are having similar problem and use this solution, be sure to look to the bottom left hand pane for the current file you are working with (to get the whole script).
You are most welcome.
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