SetState of an array of Objects in React : <p>Ok, so I'm so frustrated finding the right solution so I'm posting the problem here. Giving an answer would help me a lot, coz I'm stuck!</p>

<p>the state tree looks like this </p>

<pre><code>this.state = {
      itemList : [{
                    _id : 1234,
                   description : 'This the description',
                   amount : 100
                    }, {
                    _id : 1234,
                   description : 'This the description',
                   amount : 100
                    }],
     }
</code></pre>

<p>The problems are : </p>

<ol>
<li>can not update any specific key in the Object of the array according
to the _id</li>
<li>The previous state should remain intact</li>
</ol>
