Code for multiple choice button

gistfile1.txt

//Start of Button Listener for Button1
        mButtonChoice1.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View view){
                //My logic for Button goes in here

                if (mButtonChoice1.getText() == mAnswer){
                    mScore = mScore + 1;
                    updateScore(mScore);
                    Toast.makeText(QuizActivity.this, "correct", Toast.LENGTH_SHORT).show();

                    if(mQuestionNumber == mQuestionLibrary.getNumberOfQuestions()){
                        setContentView(R.layout.end_of_quiz);
                    }else {
                        updateQuestion();
                    }

                }else {
                    Toast.makeText(QuizActivity.this, "wrong", Toast.LENGTH_SHORT).show();

                    if(mQuestionNumber == mQuestionLibrary.getNumberOfQuestions()){
                        setContentView(R.layout.end_of_quiz);
                    }else {
                        updateQuestion();
                    }
                }
            }
        });

        //End of Button Listener for Button1

where is the "getNumberOfQuestions" involved in in other parts of the code as this is the only thing that shows an error