Question

I am new to the Android Platform and I want to fetch value’s from a PHP Web Service through JSON Parser. But I am not getting the data, rather the error: No value for data25 ,data26 and data27.

I appreciate any help sorting out this problem.

try{
            JSONArray jArray = new JSONArray(result);
            for(int i=0;i<jArray.length();i++)
            {
            HashMap<String, String> map = new HashMap<String, String>();

              JSONObject json_data = jArray.getJSONObject(i);

            map.put("data25", "date25:" + json_data.getString("data25"));
            map.put("data26", "data26:" + json_data.getString("data26"));
            map.put("data27", "data27:" + json_data.getString("data27"));

            mylist.add(map);

            }

The JSON result is as follows:

[
{
    "data1": "5794",
    "data2": "2922",
    "data3": "6799",
    "data4": "2729",
    "data5": "9860",
    "data6": "4486",
    "data7": "9903",
    "data8": "0113",
    "data9": "9936",
    "data10": "5470",
    "data11": "7423",
    "data12": "1237",
    "data13": "6564",
    "data14": "1261",
    "data15": "4730",
    "data16": "7714",
    "data17": "2410",
    "data18": "7486",
    "data19": "7046",
    "data20": "8263",
    "data21": "4305",
    "data22": "6244",
    "data23": "2495",
    "data24": " 19\/09\/2012(Wed)"
},
{
    "data1": "555",
    "data2": "039",
    "data3": "353",
    "data4": "1438",
    "data5": "8720",
    "data6": "7490",
    "data7": "1294",
    "data8": "4000",
    "data9": "6017",
    "data10": "2294",
    "data11": "4042",
    "data12": "0064",
    "data13": "8441",
    "data14": "1252",
    "data15": "9609",
    "data16": "0797",
    "data17": "1680",
    "data18": "0917",
    "data19": "7492",
    "data20": "9488",
    "data21": "3253",
    "data22": "7915",
    "data23": "1071",
    "data24": " 19\/09\/2012(Wed)",
    //--heredata25,
    data26,
    data27----------"data25": "9555",
    "data26": "3039",
    "data27": "6353"
},
{
    "data1": "0395",
    "data2": "5928",
    "data3": "8998",
    "data4": "6447",
    "data5": "1827",
    "data6": "8131",
    "data7": "7454",
    "data8": "4647",
    "data9": "1892",
    "data10": "3656",
    "data11": "1989",
    "data12": "9095",
    "data13": "6826",
    "data14": "1860",
    "data15": "9766",
    "data16": "6069",
    "data17": "6050",
    "data18": "6526",
    "data19": "8392",
    "data20": "0520",
    "data21": "7540",
    "data22": "3608",
    "data23": "7430",
    "data24": " 19\/09\/2012(Wed)"
},

Answer 1

As per the response you have posted, it is a JSONArray of JSONObjects. Each JSONObject contains the values with the keys like data1, data2…etch. But every JSONObject doesn’t contain the keys data25, data26, data27. If you don’t want to throw exception even the response does n’t contain the data25,data26, data27 keys in every JSONObject then you need to modify the code like below:

        JSONArray jArray = new JSONArray(result);
        for(int i=0;i<jArray.length();i++)
        {
        HashMap<String, String> map = new HashMap<String, String>();

          // getJSONObject() will throw exception if the key is not found in the jsonObject. Instead of it use optJSONObject() to get the values from JSONObject. It returns the value if contains otherwise returns the empty jsonObject.
          // JSONObject json_data = jArray.getJSONObject(i);
          JSONObject json_data = jArray.optJSONObject(i);


        //map.put("data25", "date25:" + json_data.getString("data25"));
         map.put("data25", "date25:" + json_data.optString("data25")); // returns empty string on not finding the key in JSONObject.

        //map.put("data26", "data26:" + json_data.getString("data26"));
        //map.put("data27", "data27:" + json_data.getString("data27"));

        mylist.add(map);

        }