Android: how to sort data for ListView?
I have JSON data that I am dumping from the server. One of the fields in this data is the distance value. I need the data to be sorted by distance from lowest to highest in the ListView. I'm not sure how to do this?
Any help is appreciated.
Is this my code for capturing data not sure how to sort it correctly?
// Hashmap for ListView
ArrayList<HashMap<String, String>> bathroomList = new ArrayList<HashMap<String, String>>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.activity_search);
getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.window_title);
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONObject json = jParser.getJSONFromUrl(url);
try {
// Getting Array of Contacts
bathrooms = json.getJSONArray(TAG_BATHROOMS);
// looping through All Contacts
for(int i = 0; i < bathrooms.length(); i++){
JSONObject c = bathrooms.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_ID);
String access = c.getString(TAG_ACCESS);
String city = c.getString(TAG_CITY);
String comment = c.getString(TAG_COMMENT);
String directions = c.getString(TAG_DIRECTIONS);
String name = c.getString(TAG_NAME);
String street = c.getString(TAG_STREET);
String bathroomtype = c.getString(TAG_BATHROOMTYPE);
String distance = c.getString(TAG_DISTANCE);
String distanceTrimmed = distance.substring(0,4) + " " + "miles away";
String avail = c.getString(TAG_AVAIL);
String country = c.getString(TAG_COUNTRY);
String state = c.getString(TAG_STATE);
String postal = c.getString(TAG_POSTAL);
//System.out.println(name);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_ID, id);
map.put(TAG_ACCESS, access);
map.put(TAG_CITY, city);
map.put(TAG_COMMENT, comment);
map.put(TAG_DIRECTIONS, directions);
map.put(TAG_NAME, name);
map.put(TAG_STREET, street);
map.put(TAG_BATHROOMTYPE, bathroomtype);
map.put(TAG_DISTANCE, distanceTrimmed);
map.put(TAG_AVAIL, avail);
map.put(TAG_COUNTRY, country);
map.put(TAG_STATE, state);
map.put(TAG_POSTAL, postal);
// adding HashList to ArrayList
bathroomList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, bathroomList,
R.layout.list_item,
new String[] { TAG_ID, TAG_NAME, TAG_STREET, TAG_CITY, TAG_STATE, TAG_POSTAL,TAG_COUNTRY, TAG_DISTANCE, TAG_DIRECTIONS, TAG_COMMENT, TAG_AVAIL, TAG_BATHROOMTYPE, TAG_ACCESS}, new int[] {
R.id.key,R.id.name, R.id.street, R.id.city, R.id.state, R.id.postal,R.id.country, R.id.distance, R.id.directions, R.id.comments, R.id.availability, R.id.bathroomtype, R.id.access });
setListAdapter(adapter);
+1
source to share
2 answers
Sorting the list using Collections.sort()
a special comparator.
Collections.sort(bathroomList, new Comparator<HashMap<String, String>>()
{
@Override
public int compare(HashMap<String, String> a, HashMap<String, String> b)
{
return a.get(TAG_DISTANCE).compareTo(b.get(TAG_DISTANCE));
}
});
+4
source to share
same problem with mine, but now i get it working, thanks to @rusmus. Have a look at Sorting Double Data (Distance) in ListView
Try this code:
Collections.sort(bathroomList, new Comparator<HashMap<String, String>>() {
@Override
public int compare(HashMap<String, String> o1,
HashMap<String, String> o2) {
return Double.compare(Double.parseDouble(o1.get(TAG_DISTANCE)), Double.parseDouble(o2.get(TAG_DISTANCE))); // error
}
});
+2
source to share