Want to add one more layer to complete the above 2 posts which are really good. If you want to go ahead and use the translation service from Joomla you can do that too by doing the following  :-

1. Step 1 Add this in your php code  , I add this to my default.php file at the top

   JText::script('COM_YOURCOMPONENT_YOUR_MESSAGE');

2. In your JS file add this code to the logic where your want to display the message

   var message = Joomla.JText._('COM_YOURCOMPONENT_YOUR_MESSAGE'); Joomla.JText.load({success: "Success"}); Joomla.renderMessages({'success': [message]});

3. In your Language/en-GB/en-GB.com_yourcomponent.ini file add the translation

   COM_YOURCOMPONENT_YOUR_MESSAGE="your message"

I want to add one more layer to complete the above 2 posts which are really good. If you want to use the translation service from Joomla, you can do that by doing the following:

1. Add this in your php code, I add this to my default.php file at the top

   JText::script('COM_YOURCOMPONENT_YOUR_MESSAGE');
   

2. In your JS file, add this code to the logic where your want to display the message

   var message = Joomla.JText._('COM_YOURCOMPONENT_YOUR_MESSAGE');
   Joomla.JText.load({success: "Success"});
   Joomla.renderMessages({'success': [message]});
   

3. In your Language/en-GB/en-GB.com_yourcomponent.ini file, add the translation

   COM_YOURCOMPONENT_YOUR_MESSAGE="your message"