Retrieving Data with JSON in Android - android

My application connects to the web and retrieves a JSON file. I am having some issues retrieving the data that I need from this file. Here is the link to the JSON file: http://api.wunderground.com/api/f9d9bc3cc3834375/forecast/q/CA/San_Francisco.json
Here is a snippet of what it looks like:
I would like to get the value of the "period" variable in the first JSon object within the "forecastday" array, which should be 0. Here is how i'm looking at this. "forecastday" is the array, within that there are a number of JSon objects, each containing variables like "period","icon"....."pop".
In my code, I attempt to get the JSON array "forecastday" and then get the first Json object of the array, I then retrieve the value of "period" in that object and set it in a TextView:
protected void onPostExecute(String response) {
if(response == null) {
response = "THERE WAS AN ERROR";
}
progressBar.setVisibility(View.GONE);
try {
JSONObject jsonObj = new JSONObject(response);
JSONArray contacts = jsonObj.getJSONArray("forecastday");
JSONObject c = contacts.getJSONObject(0);
String period = c.getString("period");
responseView.setText(period);
} catch (JSONException e) {
e.printStackTrace();
}
}
When I run the code, nothing is being retrieved. I'm new to working with JSon and am wondering if I'm looking at this wrong. Please help.

Your "forecastday" JSONArray is inside the "txt_forecast" JSONObject that is inside the "forecast" JSONObject of your response, so you have to extract your JSONArray from this JSONObject and not from the root JSON response :
try {
JSONObject jsonObj = new JSONObject(response);
--> JSONObject forecatsObj = jsonObj.getJSONObject("forecast");
--> JSONObject txtForecatsObj = forecatsObj.getJSONObject("txt_forecast");
JSONArray contacts = txtForecatsObj.getJSONArray("forecastday");
...

You were close but it is incorrect, try like this:
JSONObject jsonObj = new JSONObject(response);
JSONObject forecast = jsonObj.getJSONObject("forecast");
JSONObject txtForecast = forecast.getJSONObject("txt_forecast");
JSONArray forecastDay = txtForecast.getJSONArray("forecastday");
//parse the first period value
String period = forecastDay.getJSONObject(0).getString("period");
responseView.setText(period);

Try this code :
try {
JSONObject jsonObj = new JSONObject(response);
JSONObject forecastObj = jsonObj.getJSONObject("forecast");
JSONObject txt_forecastObj = forecastObj.getJSONObject("txt_forecast");
JSONArray foracastdayArray = txt_forecastObj.getJSONArray("foracastday");
JSONObject oOjb0 = foracastdayArray.getJSONObject(0);
String period = oOjb0.getString("perioed");
}catch (Exception e){
}

This code works for me fine:
JSONObject jsonResponse = new JSONObject(responce);
JSONArray jsonMainNode = jsonResponse.optJSONArray("forecastday");
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
String period = jsonChildNode.optString("period");
responceView.setText(period);
}

Related

Problem with using JSON when trying get more data like "fields"

I have this code to get all information from website, I did it very well and it works, but I got stuck when trying to get "fields" from the site
This is the site url:
http://content.guardianapis.com/search?order-by=newest&show-references=author&show-tags=contributor&q=technology&show-fields=thumbnail&api-key=test
Here is the code and how can I fix it
try {
JSONObject jsonRes = new JSONObject(response);
JSONObject jsonResults = jsonRes.getJSONObject("response");
JSONArray resultsArray = jsonResults.getJSONArray("results");
for (int i = 0; i < resultsArray.length(); i++) {
JSONObject oneResult = resultsArray.getJSONObject(i);
String url = oneResult.getString("webUrl");
String webTitle = oneResult.getString("webTitle");
String section = oneResult.getString("sectionName");
String date = oneResult.getString("webPublicationDate");
date = formatDate(date);
JSONArray fields = oneResult.getJSONArray("fields");
JSONArray fieldsArray=oneResult.getJSONArray("fields");
String imageThumbnail= null;
if(fields.length()>0){
imageThumbnail=fields.getJSONObject(0).getString("thumbnail");
}
resultOfNewsData.add(new News(webTitle url, date, section, imageThumbnail));
}
} catch (JSONException e) {
Log.e("FromLoader", "Err parsing response", e);
}
Because the fields object isn't an Array is a JSON object
"fields":{"thumbnail":"https://media.guim.co.uk/fa5ae6ca7c78fdfc4ac0fe4212562e6daf4dfb3d/0_265_4032_2419/500.jpg"}
An array object should contain [ JSON1, JSON2, JSON3 ]
In your case this
JSONArray fields = oneResult.getJSONArray("fields");
becomes this
JSONObject fields = oneResult.getJSONObject("fields");
And I don't understand why are you getting the same data twice - fields and fieldsArray

How can I parse a json with colon in android?

I have a json with colon between the strings, and I'm not sure how can I parse it. I know that I don't have an array in the json, but I'm not sure how can I get the values...
{
"config": {
"network": {
"hni:21407" : "num:[INTNUM]",
"hni:311490" : "num:044[INTNUM]"
}
}
}
This is what I'm trying, but I never go through the loop for, and not really sure if I need it.
JSONObject obj = new JSONObject(netWorkJson);
String arr = obj.optString("network");
for(int i = 0; i < arr.length(); i++) {
String hni = obj.getString("hni");
String num = obj.getString("num");
}
Thanks in advance
You first need to parse the inner json object "network", after that you can loop over it's keys and get the values for them one by one:
private void parseJSON(String netWorkJson) throws JSONException {
JSONObject obj = new JSONObject(netWorkJson);
JSONObject config = obj.getJSONObject("config");
JSONObject network = config.getJSONObject("network");
Iterator<?> keys = network.keys();
while(keys.hasNext()) {
String key = (String) keys.next();
String value = network.getString(key);
}
}
Beauty of this is that it will also work if you had 100 hni values for example, and that you don't have to get them one by one.
network is JSONObject instead of JSONArray, so no need to use for-loop for getting value from it.just use do it as:
JSONObject obj = new JSONObject(netWorkJson);
// get network JSONObject from obj
JSONObject network=obj.getJSONObject("network");
// get both values from network object
String strHni=network.optString("hni:21407");
String strNum =network.optString("hni:311490");
JSONObject message = new JSONObject(config);
String value=message.getJSONObject("network").getString("hni:21407")
Try This
try {
JSONObject jsonObject = new JSONObject("config");
JSONArray jsonArray = jsonObject.getJSONArray("network");
for(int i =0;i<jsonArray.length();i++){
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
String hni21407 = jsonObject1.getString("hni:21407");
String hni311490 = jsonObject1.getString("hni:311490");
}
} catch (JSONException e) {
e.printStackTrace();
}

How to break up string response?

I am receiving a String response from the following #Override method
#Override
publc void onSuccess(String response) {
....
}
The conflict I am facing is that I do not know how to break up this response into key value pairings. This is an example of the response.
{"action":{"generic_message":"test generic message"},"domains":{"key_example_one":"https:/google.com","api_root_url":"https://test.com/new/0.2/json"},"page":null}}
I have attempted to convert the string to a JSONObject, and then adding the JSONObjects to a JSONArray.
JSONObject mJObj;
try {
mJObj = new JSONObject(response);
JSONArray mJArry = mJObj.getJSONArray("action");
for (int i = 0; i < mJArry.length(); i++) {
JSONObject newObj = mJArry.getJSONObject(i);
String test2 = newObj.getString("generic_example_for_all_platforms");
}
} catch (JSONException e) {
e.printStackTrace();
}
EDIT: I am getting JSON exception that JSONArray cannot be converted to JSONObject, for the following line.
JSONArray mJArry = mJObj.getJSONArray("action");
Thanks in advante
You do want to read more about JSON here.
The first thing to know is that {} is equal to a Json Object and [] is equal to a Json Array.
try {
JSONObject mJObj = new JSONObject(response);
JSONObject actionJsonObject = mJObj.getJSONObject("action");
String generic_message = actionJsonObject.getString("generic_message");
JSONObject domainsJsonObject = mJObj.getJSONObject("domains");
String key_example_one = domainsJsonObject.getString("key_example_one");
String api_root_url = domainsJsonObject.getString("api_root_url");
String page = mJObj.getString("page");
} catch (JSONException e) {
e.printStackTrace();
}
Check out Gson.
JsonObject jsonObject = new JsonParser().parse(jsonString).getAsJsonObject();
EDIT:
Just saw that you can't move to other Json processors. The property 'action' holds a JSONObject not a JSONArray. What about JSONObject jsonObject = mJObj.getJSONObject("action").

JSONObject from string on Android

l get string with answer from server. l want to do it JSONObject.
l do
JSONObject jsonObj = new JSONObject(json);
in json has
"{"sentences":[{"trans":"R\u0455R\u0491ReR\u0405","orig":"�\u0455�\u0491��\u0405","translit":"","src_translit":"R\u1E91Rg\u0300RoR\u1E90"}],"src":"ru","server_time":1}"
but jsonObj has
"{"sentences":[{"src_translit":"RẑRg̀RoRẐ","orig":"�ѕ�ґ��Ѕ","trans":"RѕRґReRЅ","translit":""}],"server_time":1,"src":"ru"}"
so how l can get value from "trans":"RѕRґReRЅ"?
PS RѕRґReRЅ it's "own" in normal charset
If you already have the jsonObj you just have to do:
try {
// Getting Array of Sentences
sentences = json.getJSONArray("sentences");
// looping through All Contacts
for(int i = 0; i < sentences.length(); i++){
JSONObject c = sentences.getJSONObject(i);
// get the value from trans
String trans = c.getString("trans");
//now you should save this string in an array
}
} catch (JSONException e) {
e.printStackTrace();
}
try this
JSONObject jsonObj = new JSONObject(json);
JSONArray sentences = jsonObj.getJSONArray("sentences");
for(int i=0;i<sentences.length();i++){
JSONObject number = sentences.getJSONObject(i);
String transValue = number.getString("trans");
}
First you have to remove single quote form starting and from ending of your JSON string (json), by this your JSON will be a valid json for this you have to do like :
json= json.substring(1, json.length()-1);
After that you do like this :
JSONObject oJsonObject = new JSONObject(json);
JSONArray oJsonArray = oJsonObject.getJSONArray("sentences");
for(int i=0; i<oJsonArray.length(); i++)
{
JSONObject oJsonObject1 = oJsonArray.getJSONObject(i);
String transValue = oJsonObject1 .getString("trans");
}

Problems with getting values from JSON object

I'm trying to get data once user logged in successfully but I never get any of results, what I am doing is next:
// response is my request to server
JSONObject obj = new JSONObject(response);
Log.d("RESPONSE",obj.toString());
so in log I do see values, like:
04-19 11:28:16.729: D/RESPONSE(3162): {"data":[{"loses":3,"username":"benedict","level":1,"strength":15,"experience":null,"gold":10,"password":"benedict","intelligence":5,"agility":10,"wins":5}],"status":true}
but once I try to read username for example like this:
String username = obj.getString("username");
The code above ^ gives me nothing in my string..
Any help how I can retrieve data from JSONObject? Thanks!
That is because the username is present in the data object, which happens to be an JSONArray. Get the data array from the response object, traverse through each JSONObject in the array, and from each object, extract your username.
Something like this:-
JSONObject obj = new JSONObject(response);
JSONArray data = obj.getJSONArray("data");
for(int i=0;i<data.length();i++){
JSONObject eachData = data.getJSONObject(i);
System.out.println("Username= "+ eachData.getString("username"));
}
your field username is in array data. To access into this try :
JSONObject obj = new JSONObject(response);
JSONArray array = obj.getJSONArray("data");
for(int i = 0; i < array.length(); ++i){
JSONObject data = array.getJSONObject(i);
String username = data.getString("username");
}
You need to first get JSONArray which is data :
JSONArray data = null;
data = json.getJSONArray("data");
for(int i = 0; i < data.length(); i++){
JSONObject c = data.getJSONObject(i);
String username = c.getString("username");
}
You can get idea about parsing JSON from HERE
Try this...
try {
JSONObject object = new JSONObject(response);
JSONArray Jarray = object.getJSONArray("data");
for (int i = 0; i < Jarray.length(); i++) {
JSONObject Jasonobject = Jarray.getJSONObject(i);
String loose= Jasonobject.getString("loses");
String username=Jasonobject.getString("username");
.......
........
}
} catch (JSONException e) {
Log.e("log_txt", "Error parsing data " + e.toString());
}

Categories

Resources