title: React-native flatlist renderItem
body: <p>I have a array dictionary. I want to render all value to flatlist. 
  I try:<br></p>
  
  <blockquote>
    <p>renderItem = {({item}) => item.A.id}</p>
  </blockquote>
  
  <p>But I don't return any value. Please help me. thanks</p>
  
  <pre><code>ArrAccount: {
    "A": [
      {
        "id": 1,
        "name": "Anh Tuan Nguyen",
        "age": 28
      },
      {
        "id": 2,
        "name": "An Nhien",
        "age": 2
      },
    ],
    "Z": [
      {
        "id": 3,
        "name": "Thanh Tu Pham",
        "age": 32
      },
      {
        "id": 4,
        "name": "Tien Thanh",
        "age": 24
      },
    ]
  }
  </code></pre>