CODEWITHSUNDEEP
androidandroid-asynctask
leonidas56
leonidas56

Reputation: 915

Waiting for AsyncTask postExecute to continue

I am pretty new with the concept of asynctask and i have an asynctask that gets me a json from an api with parameter an then(postexecute) puts the content inside textviews to be shown(they are set visible after setting the text), the thing is i am trying to validate that the json isnt actually empty, and with my code i actually do that, but if the parameter i use is correct, the validation still detects that its empty, if i try to get it again(by pressing the button that triggers the asynctask) after 2 or three tries it will actually get it tho, i think its because i am doing it on the background, here is the asynctask

 private class ConsultarDatos extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... urls) {

        // params comes from the execute() call: params[0] is the url.
        try {
            return downloadUrl(urls[0]);
        } catch (IOException e) {
            return "Unable to retrieve web page. URL may be invalid.";
        }
    }
    // onPostExecute displays the results of the AsyncTask.
    @Override
    protected void onPostExecute(String result) {

        JSONArray ja = null;
        try {
            ja = new JSONArray(result);
            txtNombre.setText(ja.getString(0) +" " + ja.getString(1));
            txtCategoria.setText(ja.getString(2));
            txtDNI.setText(ja.getString(3));
            txtEstado.setText(ja.getString(4));
            //working=false;



        } catch (JSONException e) {
            e.printStackTrace();
        }

    }
}

and here is what i am trying to do

        btnGenerar.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            new ConsultarDatos().execute("https://api-adress/file.php?DNI=" + etDNI.getText().toString());

            //while(working)
            //{

            //}
            if (txtCategoria.getText()!="") {
                btnGenerar.setVisibility(View.INVISIBLE);
                etDNI.setVisibility(View.INVISIBLE);
                txtCategoria.setVisibility(View.VISIBLE);
                txtDNI.setVisibility(View.VISIBLE);
                txtEstado.setVisibility(View.VISIBLE);
                txtNombre.setVisibility(View.VISIBLE);
                imgTarjeta.setVisibility(View.VISIBLE);

            }
            else
            {
                Toast.makeText(getApplicationContext(),"DNI Incorrecto",Toast.LENGTH_LONG).show();
            }

        }
    });

as i commented i tried to do a while that would wait until the textsviews are all set but that just crashed my app

Upvotes: 0

Views: 44

Answers (2)

leonidas56
leonidas56

Reputation: 915

I resolved it, just moved the the visibility set and validation to the end of the onPostExecute and just to be sure i put the toast in the exception too just so the user gets some feedback

 protected void onPostExecute(String result) {
        JSONArray ja = null;
        try {
            ja = new JSONArray(result);
            txtNombre.setText(ja.getString(0) +" " + ja.getString(1));
            txtCategoria.setText(ja.getString(2));
            txtDNI.setText(ja.getString(3));
            txtEstado.setText(ja.getString(4));

            if (txtCategoria.getText()!="") {
                btnGenerar.setVisibility(View.INVISIBLE);
                etDNI.setVisibility(View.INVISIBLE);
                txtCategoria.setVisibility(View.VISIBLE);
                txtDNI.setVisibility(View.VISIBLE);
                txtEstado.setVisibility(View.VISIBLE);
                txtNombre.setVisibility(View.VISIBLE);
                imgTarjeta.setVisibility(View.VISIBLE);

            }
            else
            {
                Toast.makeText(getApplicationContext(),"DNI Incorrecto",Toast.LENGTH_LONG).show();
            }



        } catch (JSONException e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),"DNI Incorrecto",Toast.LENGTH_LONG).show();

        }

    }

Upvotes: 1

Corey Johnson
Corey Johnson

Reputation: 114

Use something like https://www.getpostman.com/ to see what the result of your API call is. Right now it seems like you don't know what you're getting back, and how consistently it comes back. You need to validate that your server is sending you back valid data.

Using a json library to parse the JSON response, such as GSON or Moshi would help you out as well. Right now you're trying to get the values based on arbitrary numbers. You could be having an exception from just one field missing, but there's not enough info to tell. Gson is fairly easy to set up in my experience: https://github.com/google/gson

Upvotes: 0

Related Questions