Question

How to save List<UserDefinedClass> of between Activity switching ? I get data in onClickView function. Does UserDefinedClass need to implements some interface ?

Answer 1

I believe the best way would be to keep the list in the Application context.

In any of your activitys call yourApp using:

((yourApp)getApplication()).//any public function

---

public yourApp extends Application{
    private List<UserDefinedClass> yourList;

    //create functions to manipulate the list example:
    public void add(UserDefinedClass a){
        //add this to list
    }

    //finally function to access list
    public List<UserDefinedClass> getList(){
        return yourList;
    }
}

---

//example:
List<UserDefinedClass> aList = ((yourApp)getApplication()).getList();