从另一个类中获取变量

Question

I have to spinners, and when I start my app, the PHP only returns values of spinner's first choice. First code is part of one class (IzboraGrada.java)

public void addListenerOnButton() {
        spinner1=(Spinner) findViewById(R.id.spinner1);
        spinner2=(Spinner) findViewById(R.id.spinner2);
        button=(Button) findViewById(R.id.button);
        str_grad=spinner1.getSelectedItem().toString();
        str_predmet=spinner2.getSelectedItem().toString();

        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {


            Intent i=new Intent (v.getContext(), MainActivity.class);
            url = "http://192.168.1.102/test/spinner.php";
            url=url+"?grad="+str_grad+"&predmet="+str_predmet;
            i.putExtra("URL",url);

            startActivity(i);

            }
        });

And the second code is part of MainActivity.class that was in intent.

private void initView() {
        // show progress dialog
        dialog = ProgressDialog.show(this, "", "Loading...");

        String url = "http://192.168.1.102/test/spinner.php";

        Bundle extras = getIntent().getExtras();
        if (extras != null) {
            url = extras.getString("URL");
        }         
        FetchDataTask task = new FetchDataTask(this);
        task.execute(url);
    }

I presume that's because str_grad and str_predmet are not defined in second class. But If I put str_grad and str_predmet in second class, they are can't be resolved as type.Any ideas what to do?

Answer 1

It looks like you are calling this method at the beginning, before an item is selected, so I think the problem is that you are setting the values for str_grad and str_predmet when they are first set so the selected item is the default item. Those are getter functions not listeners.

You need to move those lines inside the onClick() or use onItemSelected() on your Spinners to set those variable values

public void addListenerOnButton() {
    spinner1=(Spinner) findViewById(R.id.spinner1);
    spinner2=(Spinner) findViewById(R.id.spinner2);
    button=(Button) findViewById(R.id.button);


    button.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

       str_grad=spinner1.getSelectedItem().toString();    // move these lines here
       str_predmet=spinner2.getSelectedItem().toString();

        Intent i=new Intent (v.getContext(), MainActivity.class);
        url = "http://192.168.1.102/test/spinner.php";
        url=url+"?grad="+str_grad+"&predmet="+str_predmet;
        i.putExtra("URL",url);

        startActivity(i);

        }
    });

If I understand your problem correctly, that should solve your problem.