title: jTextField update in real time based on other jTextFields values?
body: <p>I have a quick question to ask.</p>
  
  <p>The problem is that I need a jTextField to update its values according to a users input in other 3 other jTextFields.
  One txtfield is "idQuarto" which basically is how I know the price of the room.
  The other txtfields are Dates (Checkin &amp; Checkout), I calculate the days between them.</p>
  
  <p>This is where I need help, the textfield (Total) is where I want it to update based on the users input of dates and room id. (Price of ID Quarto * Days).</p>
  
  <p>Here is a picture of the program: <a href="http://gyazo.com/a7e47227a0be9f5720c005e61a1951d9" rel="nofollow">http://gyazo.com/a7e47227a0be9f5720c005e61a1951d9</a></p>
  
  <p>Hope everybody understands what I mean.</p>
  
  <p>Thanks.</p>