Check out example codes for "drop down menu html size". It will help you in understanding the concepts better.

Code Example 1

<label for="cars">Choose a car:</label>

<select id="cars" size="3"> #Heres how to set the size :)

  
 <option value="volvo">Volvo</option>

  
 <option value="saab">Saab</option>

  
 <option value="opel">Opel</option>

  
 <option value="audi">Audi</option>

 </select>

Learn ReactJs, React Native from akashmittal.com