Waiting for AsyncTask postExecute to continue

Issue

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

Solution

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();

        }

    }

Answered By - leonidas56