title: Bootstrap Dropdown is not working in React
body: <p>I include a dropdown button to React from bootstrap Dropdowns, But it is not working and shows as a normal button. Can you give me a solution for this?</p>
  
  <pre><code>&lt;div className="dropdown"&gt;
      &lt;button className="btn btn-secondary 
                   dropdown-toggle" 
                   type="button" 
                   id="dropdownMenuButton"
                   data-toggle="dropdown"
                   aria-haspopup="true" 
                   aria-expanded="false"&gt;
                   Dropdown button
      &lt;/button&gt;
              &lt;div className="dropdown-menu" aria-labelledby="dropdownMenuButton"&gt;
                  &lt;a className="dropdown-item" href="#"&gt;Action&lt;/a&gt;
                  &lt;a className="dropdown-item" href="#"&gt;Another action&lt;/a&gt;
                  &lt;a className="dropdown-item" href="#"&gt;Something else here&lt;/a&gt;
              &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>The output is a normal button like this. <a href="https://i.stack.imgur.com/PAE7R.png" rel="noreferrer"><img src="https://i.stack.imgur.com/PAE7R.png" alt="enter image description here"></a></p>