应用程序在尝试报告错误时收到错误

Question

so I'm using the androidhive tutorial to make a server for my app and connect to it. I have it so the server will send back different messages depending on what was sent in but I'm getting an error with it and I can't figure out why. Here is the class that the error occurs in:

class CreateNewSpot extends AsyncTask<String, String, String> {

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(NewSpotActivity.this);
        pDialog.setMessage("Creating Spot..");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    /**
     * Creating product
     * */
    protected String doInBackground(String... args) {
        String name = inputName.getText().toString();
        String longitude = inputLong;
        String latitude = inputLat;
        String pavement = spinner_pavement.getSelectedItem().toString();
        String traffic = spinner_traffic.getSelectedItem().toString();
        String environment = spinner_enviro.getSelectedItem().toString();
        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("name", name));
        params.add(new BasicNameValuePair("longitude", longitude));
        params.add(new BasicNameValuePair("latitude", latitude));
        params.add(new BasicNameValuePair("pavement", pavement));
        params.add(new BasicNameValuePair("traffic", traffic));
        params.add(new BasicNameValuePair("environment", environment));

        // getting JSON Object
        // Note that create product url accepts POST method
        JSONObject json = jsonParser.makeHttpRequest(url_create,
                "POST", params);

        // check log cat fro response
        Log.d("Create Response", json.toString());

        // check for success tag
        try {
            int success = json.getInt(TAG_SUCCESS);
            switch(success){
            case 0:
                //name is empty!
                break;
            case 1:
                // successfully created product
                Intent i = new Intent(getApplicationContext(),
                        AllSpotsActivity.class);
                startActivity(i);

                // closing this screen
                finish();
                break;
            case 2:
                //name has been taken
                Toast.makeText(getApplicationContext(), "Name for spot has already been taken.", Toast.LENGTH_LONG).show();
                break;
            case 3:
                //server error
                Toast.makeText(getApplicationContext(), "A server error has occurred.", Toast.LENGTH_LONG).show();
                break;
            default:
                Toast.makeText(getApplicationContext(), "An unknown error has occurred.", Toast.LENGTH_LONG).show();
                //just an unknown error
                break;
            }

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

        return null;
    }

    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) {
        // dismiss the dialog once done
        pDialog.dismiss();
    }
}

Now I'm purposely sending in data to get success==2 but it tells me my app unexpected error has occurred. Why is this? Is it because of the pDialog is still open? I tried putting pDialog.dismiss(); above but I still get the error. Sorry if this is a simple question and thank you in advance.

Tyler

EDIT: Logcat:

    class CreateNewSpot extends AsyncTask<String, String, String> {

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(NewSpotActivity.this);
        pDialog.setMessage("Creating Spot..");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    /**
     * Creating product
     * */
    protected String doInBackground(String... args) {
        String name = inputName.getText().toString();
        String longitude = inputLong;
        String latitude = inputLat;
        String pavement = spinner_pavement.getSelectedItem().toString();
        String traffic = spinner_traffic.getSelectedItem().toString();
        String environment = spinner_enviro.getSelectedItem().toString();
        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("name", name));
        params.add(new BasicNameValuePair("longitude", longitude));
        params.add(new BasicNameValuePair("latitude", latitude));
        params.add(new BasicNameValuePair("pavement", pavement));
        params.add(new BasicNameValuePair("traffic", traffic));
        params.add(new BasicNameValuePair("environment", environment));

        // getting JSON Object
        // Note that create product url accepts POST method
        JSONObject json = jsonParser.makeHttpRequest(url_create,
                "POST", params);

        // check log cat fro response
        Log.d("Create Response", json.toString());

        // check for success tag
        try {
            int success = json.getInt(TAG_SUCCESS);
            switch(success){
            case 0:
                //name is empty!
                break;
            case 1:
                // successfully created product
                Intent i = new Intent(getApplicationContext(),
                        AllSpotsActivity.class);
                startActivity(i);

                // closing this screen
                finish();
                break;
            case 2:
                //name has been taken
                error_msg = 0;
                break;
            case 3:
                //server error
                error_msg = 1;
                break;
            default:
                error_msg = 2;
                //just an unknown error
                break;
            }

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

        return null;
    }

    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) {
        // dismiss the dialog once done
        switch(error_msg){
        case 0:
            Toast.makeText(getApplicationContext(), "Name for spot has already been taken.", Toast.LENGTH_LONG).show();
            break;
        case 1:
            Toast.makeText(getApplicationContext(), "A server error has occurred.", Toast.LENGTH_LONG).show();
            break;
        case 2:
            Toast.makeText(getApplicationContext(), "An unknown error has occurred.", Toast.LENGTH_LONG).show();
            break;
        default:
            break;
        }
        pDialog.dismiss();

    }
 }

Answer 1

You are getting unexpected error because you are showing Toast from doInBackground(), which you can't do. You never handle your UI from background in AsyncTask. Just remove your try-catch block from doInBackground() to onPostExecute() and it will work.