title: Passing a text field value into popup page using URL
body: <p>I am trying to pass the value of a text field from one page to another using the URL but failing miserably.</p>
  
  <p>The reason for this is as follows:
  I have an apex page which displays a machines properties (make, model, what products it makes, machine ID (:P1_INPUT)). Some machines can only make one product, other can make a variety.</p>
  
  <p>I use a query to complete the following: If the machine only makes one type of product , the product number is displayed in :P1_item. If a machine can make more than one product it displays in :P1_item the world 'multiple'.</p>
  
  <p>I want to build in the ability to click on a button next to :P1_Item, a popup appears with the products the machine makes if ‘multiple’ is displayed. I have the popup bit working but its not passing my :P1_INPUT from the page to the popup page text field :P3_OUPUT
  The following code i have on the button, so when it is clicked, it opens a popup page (this works) and should populate the text field (P3_OUTPUT) with the value passed from P1_INPUT (this doesnt work).</p>
  
  <p>My button is set to Redirect to URL and i have this in the URL target.</p>
  
  <pre><code>javascript:popupURL('f?p=&amp;APP_ID.:HELLOWORLD:&amp;SESSION.:::&amp;P3_OUTPUT.:&amp;P1_INPUT.')
  </code></pre>
  
  <p>I cant use a branch because i dont want the main page showing the machine properties to submit.</p>