Save data from a web service to a global variable on Android

Question

i am starting with Android programming and am having a problem. I would like to store the response of my webservice in a global variable. This webservice returns a Boolean value, this value I would like to store in the connected global variable. But the way I did, below, when leaving the class Conectabdtask this variable [connected] is always false. I have already run in Debug mode and the return of the webservice is true. Could you help me solve this problem? Thanks!

public class LoginActivity extends Activity {

    private boolean conectado;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        conectado = false;
        new ConectaBdTask().execute();
    }


    private class ConectaBdTask extends AsyncTask<Void, Void, Boolean> {

        //quando doInBackground termina, é chamado o onPostExecute com o retorno do doInBackground
        @Override
        protected Boolean doInBackground(Void... params) {
            try {
                final String url = "localhost/conectarBd";
                RestTemplate restTemplate = new RestTemplate();
                restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

                //faz a requisição ao Web Service
                Boolean conectado = restTemplate.getForObject(url, Boolean.class);

                return conectado;
            } catch (Exception e) {
                Log.e("MainActivity", e.getMessage(), e);
            }

            return Boolean.FALSE;
        }


        protected void onPostExecute(Boolean conectado) {

            LoginActivity.this.conectado = conectado;

        }

    }
}

Answer 1

You can create a Singleton class and store the data there, I have a class of this kind here

https://github.com/xanexpt/flickr/blob/master/app/src/main/java/com/badjoras/baamflickr/AppSingleton.java

in that class you create getters and setters for the variables you want to store, then you can access "anywhere" this way

AppSingleton.getInstance().setAdsResponse(response.body());
AppSingleton.getInstance().getAdsById(adId);

EDIT: Don’t do as it says in the previous answer, storing things in the Application class is high hammer...

Answer 2

Fala Gabriel,

You must create a class that extends Application, example:

public class MyApplication extends Application {

    private String someVariable;

    public String getSomeVariable() {
        return someVariable;
    }

    public void setSomeVariable(String someVariable) {
        this.someVariable = someVariable;
    }
}

There on your Androidmanifest.xml, you should change the name of the application tag that way:

<application 
  android:name=".MyApplication" 
  android:icon="@drawable/icon" 
  android:label="@string/app_name">

Then, to set a variable, use:

// set
((MyApplication) this.getApplication()).setSomeVariable("foo");

And to rescue it anywhere in the app, use:

// get
String s = ((MyApplication) this.getApplication()).getSomeVariable();

Hugs.