title: Android|Kotlin recyclerView update one item
body: <p>I have this issue:</p>
  
  <p>I'm using a recycler view in my app but the thing is that I need to update one single item of my recycler view.</p>
  
  <p>When I click on the recycler view item, it sends me to another screen where I update the value and returned (this is working, I get the values on back)</p>
  
  <p>I tried to add a new function inside my adapter as follows:</p>
  
  <pre><code>public fun updateItem(updatedOI: ArrayList&lt;OrderItem&gt;){
          orderItem = updatedOI
          notifyDataSetChanged()
      }
  
  </code></pre>
  
  <p>and then call the function from my fragment/activity but it is not working.</p>
  
  <p>I basically need to grab the index somehow and update that single index what it is doing now is removing all of the items and just add the updated one.</p>
  
  <p>How do I fix this issue?</p>