title: Populate a second DropDownList based on a selected value from other DropDownList
body: <p>I’m trying to link two dropdownlist depending on the value you select from the first dropdownlist.
  I don’t have any idea how to do this, so if you guys can point me in the right direction that would be great.</p>
  
  <p>What I want to do is select a value from the first dropdownlist and depending on its value show some options in the second dropdownlist.</p>
  
  <p>I try doing this:</p>
  
  <p>1-when the “OnChange” event of the first dropdownlist occurs, I call a javascript that redirects to a method in a controller (for example: index/mainController/firstMethod/selectedValue).</p>
  
  <p>2-the method in the controller using the url helper extracts the “selectedValue” to do a database search of the value of the second dropdownlist.</p>
  
  <p>3-the same method loads the view (the one that have the ddl)</p>
  
  <p>Doing this I lose the selected value of the first ddl.</p>
  
  <p>I think this is not the right way to do it.</p>
  
  <p>So, once again, I need some help.</p>