title: How to make child to fit height in a Row in flutter?
body: <p>I have a <code>Row</code> widget with the Input files and search button. And the Row is inside A Column.</p>
  <p><a href="https://i.stack.imgur.com/E2ih9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/E2ih9.png" alt="enter image description here" /></a></p>
  <p>How do I make a search button to fit the height of the row, Making the button size equal to the Input field height?</p>
  <p>I Tried adding <code>crossAxisAlignment: CrossAxisAlignment.stretch,</code> to the Row but getting the error:-</p>
  <p><code>BoxConstraints forces an infinite height.</code></p>
  <p>I don't have the height of the input field. And not want to hardcode the height of the button as it should always match the height of the Input box.</p>
  <p>Also, Assigning the height to the Row and adding <code>CrossAxisAlignment.stretch</code> does not change the height of the Input Field, the only button is changing.</p>
  <p>What is the issue here and how to fix this?</p>
  <pre><code>Row(
    // crossAxisAlignment: CrossAxisAlignment.stretch,
    mainAxisAlignment: MainAxisAlignment.center,
    children: [
      Expanded(
        child: Container(
          child: TextField(
            decoration: InputDecoration(
              border: InputBorder.none,
              hintText: 'search',
              hintStyle:
                  Theme.of(context).textTheme.bodyText2.copyWith(
                    color: Theme.of(context).accentColor,
                  ),
              contentPadding: EdgeInsets.symmetric(
                vertical: 8, horizontal: 20
              ),
              fillColor: Theme.of(context).primaryColor,
              filled: true,
            ),
            style: Theme.of(context).textTheme.bodyText2,
          ),
        ),
      ),
      FlatButton(
        onPressed: () {},
        color: Colors.grey,
        child: Icon(
          Icons.search,
        ),
      ),
    ],
  )
  </code></pre>