pinner = findViewById(R.id.spinnerManual);
        pdfView = findViewById(R.id.viewPdf);

        ArrayList<ManualClass> manuals = new ArrayList<>();
        ManualClass manual = new ManualClass();
        manuals = manual.fillArrayList();

        //ArrayAdapter populates the spinner with manual objects
        ArrayAdapter<ManualClass> adapter = new ArrayAdapter<ManualClass>(this, android.R.layout.simple_spinner_item, manuals);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        //Allows spinner to show the populated objects
        spinner.setAdapter(adapter);

        //Changes the PDF when new item is selected
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
                ManualClass man = (ManualClass) spinner.getSelectedItem();
                displayManualData(man, pdfView); //when item is selected this function displays the pdf
            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {

            }
        });

    }

    private void displayManualData(ManualClass man, PDFView pdf){
        String url = man.getUrl();

        new RetrievePDFStream(pdf).execute(url);

        //takes the URL out of ManualClass Object and sends it to RetrievePDFStream to be run
    }