title: How to make JSONArray empty or delete it
body: <p>After completion of execution of an activity i want to make jSONArray empty or delete it. Because when i am calling the activity repeatedly the new data gets append to the old data present in JSONArray. My jsonArray is as shown below..</p>
  
  <pre><code>[{"record":[
              {......},
              {.......}
             ]
   },
   {"record":[
              {..........},
              {.........}
             ]
   }
  ] 
  
  
  First time:
  [{"record":[{"intensity":"Low","Body_SubParts":"Scalp","symptom":"Bleeding"}]}]
  
  Second time:
  [{"record":[{"intensity":"Low","Body_SubParts":"Scalp","symptom":"Bleeding"},
  {"intensity":"Low","Body_SubParts":"Eyes","symptom":"Bleeding"}]}]
  </code></pre>