title: Knowing which child have been changed from inside `onDataChange` Firebase Android
body: <p>This is my Firebase Database structure</p>
  
  <pre><code>"randomParentID" : {
    "description" : "my description is here",
    "meetings" : {
      "randomidmeetings2" : true
    },
    "members" : {
      "WoZ3X4OZBuRepEuZZ0mUONa5h1a2" : true,
      "fjshtY3lFdWott5Zd6lr9rJSy7z1" : true
    },
    "title" : "my title"
  }
  </code></pre>
  
  <p>I need to know when any value inside <code>randomParentID</code> is changed. So I placed <code>addValueEventListener</code> there.</p>
  
  <p>But I also want to add <code>addChildEventListener</code> into <code>meetings</code> and <code>members</code> node to know more specific which data is added or removed.</p>
  
  <p>With that, when I only want <code>onChildAdded</code> (or removed or changed) to be called, I will also get <code>onDataChange</code> (from listener of <code>randomParentID</code>) get called.</p>
  
  <p>My question is, is there any way to know which of the children node that has been changed from inside <code>onDataChange</code> so that I can skip it when the data that been changed is <code>meetings</code> or <code>members</code>. event altogether. Thanks</p>