App Inventor with Javascript Classes

Hi in the moment i use blocky to write my programm. This is easy for some programms. But i would prefered to work with the Java Script Object classes and her Methods.

Is there a way to work on this way?
thanks

Javascript and App Inventor

https://appinventor.mit.edu/explore/ai2/webview-javascript

Are these any help?

I think i would misuderstand..
I want to programm like in java.
In a Web Page i will import the used classes
and in a java_sript block i will use Objects and her methods like documented for example here User Interface
Button btn1=new Button();
btn1.setText("xxxxx");

and so on.
I dont wonna use blocky elements

what libraries i had to import