title: Oracle APEX | How to change select list value and Submit it dynamically
body: <p>I have two select lists</p>
  
  <p><strong>1. The first one P4_country_id_B contains countries names</strong></p>
  
  <pre><code>    select country_name as d, country_id as r 
      from countries
  </code></pre>
  
  <p><strong>2. The second one P4_CITY_ID_B contains cities of a country based on selected value in P4_CITY_ID_B.</strong></p>
  
  <pre><code>    select city_name as d, city_id as r 
      from cities 
      where country_id = :P4_country_id_B
  </code></pre>
  
  <p>Everything goes OK without any problem.</p>
  
  <p><strong>BUT</strong> </p>
  
  <p>I use <strong>Execute PL/SQL Code Dynamic Action</strong> to change selected values of those lists like this (for example):</p>
  
  <pre><code>:P4_country_id_B:=country_returned_value;
  :P4_CITY_ID_B:=city_returned_value;
  </code></pre>
  
  <p><strong>Where</strong></p>
  
  <pre><code>country_returned_value : is a one value of countries list values for example (USA)
  city_returned_value    : is a one value of cities list values for example (NewYourk). 
  </code></pre>
  
  <p>The first selected list value changes <strong>but</strong> the second list never changes.</p>
  
  <p><strong>Notes:</strong> </p>
  
  <ul>
  <li>I used P4_country_id_B,P4_CITY_ID_B as <strong>Page Items to Submit</strong> for the dynamic action.
  
  <ul>
  <li>I don't whan to submit the page instead of dynamic action</li>
  </ul></li>
  </ul>
  
  <p><strong>How can I change list values in this case please?.</strong></p>
  
  <p><strong>Thanks in advance.</strong></p>