title: How to re-render parent component from child component
body: <p>parent component has a p tag which animate it's inner text. animation works when i refresh the page.</p>
  <p>here is the Parent component:</p>
  <pre><code>import React, { Component } from 'react';
  import Child from './Child';
  
  class Parent extends Component {
      rerender=()=&gt;{
          this.forceUpdate()
      }
      render() {
          return (
              &lt;div&gt;
                  &lt;p className='animate-left'&gt;Animation&lt;/p&gt;
                  &lt;Child rerender={this.rerender}/&gt;
              &lt;/div&gt;
          );
      }
  }
  
  export default Parent;
  </code></pre>
  <p>here is the Child component:</p>
  <pre><code>import React, { Component } from 'react';
  
  class Child extends Component {
      clickHandler=()=&gt;{
          this.props.rerender()
      }
      render() {
          return (
              &lt;div&gt;
                  &lt;button onClick={this.clickHandler}&gt;Click&lt;/button&gt;
              &lt;/div&gt;
          );
      }
  }
  
  export default Child;
  </code></pre>
  <p>i want to animate again/ re-render parent component by clicking the button of child component.
  How to do that?</p>