Android calling class functions from second class

How can I call a function defined in class#A from class#B? Class#B extends AsynchTask and fetches remote data from a web service. The class#A function I am attempting to call from class#B is used to send the retrieved remote data for Class#A to display.

I am trying to pass the current instance of class#A to class#B using this but that just passes the context so the functions are not recognized.

I also tried using static but as the function runs a new thread, defining the function as static generates a compiler error.

The code I am trying to call is as follows:

public void test(List<DATA> Data){
        this.Data = Data;
        runOnUiThread(new Runnable() {          

            @Override
            public void run() {
                // TODO Auto-generated method stub
                for(DATA data : MainActivity.this.Data){
                    Toast.makeText(MainActivity.this, data.title, Toast.LENGTH_SHORT).show();
                }
            }
        });
    }

This is how you would do it:

In MainActivity:

ClassBAsyncTask mat = new ClassBAsyncTask(this, .., ..);

ClassBAsyncTask's contructor:

public ClassBAsyncTask(MainActivity context, .., ..) {
    mContext = context;
    ....
    ....
}

To call MainActivity's method test(List<DATA>) from within ClassBAsyncTask:

((MainActivity)mContext).test(yourListVariable);

Look into weak references to make sure that the AsyncTask does not use mContext when the activity no longer exists.