How do I add a Progress Bar when a user selects a spinner item that triggers a http request. Do I add it to the class doing the http request (dataCall) or the main activity that has the spinner in it?
I have a class DataCall that when called does a http call to a php script that gets data from a MySQL database and returns data in a JSON format. This class is called after a spinner item is selected. The data returned is added to another spinner in the same activity. I am trying to show the progress wheel when the class DataCall is doing its thing. Below is my code for calling DataCall from my MainActivity and the code from DataCall .
MainActivity that calls DataCall (See below) when the spinner is selected. When DataCall returns data it updates another spinner with the new data.
statespinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,long arg3)
{
int id = parent.getId();
if (spinner1_count2 < spinner1_count1 ) {
spinner1_count2++; }
else
{
city.clear();
String item = statespinner.getSelectedItem().toString();
String spinnerContentType = "city";
String spinnerURL = "getStoreCity.php?state=" + item;
//CALLING DATACALL BELOW
String city_data = DataCall.getJSON(spinnerURL,spinnerContentType);
Log.d(TAG, city_data);
String state_spinner_log = "STATE SPINNER";
Log.d(TAG, state_spinner_log);
JSONArray jsonArray;
try {
cityjsonArray = new JSONArray(city_data);
for (int i=0; i<cityjsonArray.length(); i++)
{
String styleValue2 = cityjsonArray.getJSONArray(i).getString(0);
Log.d(TAG, styleValue2);
city.add(styleValue2);
adapter2.notifyDataSetChanged();
}
//
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
// TODO Auto-generated method stub
}
});
DataCall Class:
public class DataCall extends Activity {
private static final String TAG = "MyApp";
public static String getJSON(String myUrlString, String contentType){
String line = null;
String tag_value = null;
try {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpPost = new HttpGet("http://www.mywebsite.com/getdata/" + myUrlString);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
line = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
line = "<results status=\"error\"><msg>Can't connect to server1</msg></results>";
} catch (MalformedURLException e) {
line = "<results status=\"error\"><msg>Can't connect to server2</msg></results>";
} catch (IOException e) {
line = "<results status=\"error\"><msg>Can't connect to server3</msg></results>";
}catch (Exception anything) {
//Whatever
}
return line;
}
}
I think you’re going to have to move this web call out to a different thread as it will take an unknown amount of time to run and may cause an ANR.
If you use ASyncTask it has an inbuilt mechanism for updating a progress bar as the background thread runs. There is a lot of valuable information at this link
http://www.vogella.de/articles/AndroidPerformance/article.html
Hope this helps, m