title: How to get filtered object length
body: <p>I am trying to show that there is no data to display when the size of filtered object is zero. Is there any way to check its size after calling filter method?</p>
  
  <pre><code>this.state.items
  .filter(item =&gt; {
      // filter code
  })
  .map(item =&gt; {
      // display data
  })
  </code></pre>
  
  <p>For example, this.state.items has ten items and becomes zero after passing through filter method. I'd like to display the message at this point.</p>