// Setter Method. Here we set the value to 20% and change the info message, in a 1 second animation
apex.item('P20_PROGRESS_BAR').setValue('20:Loading...:1000');

// Getter Method. This will return "20:Loading...". The animation duration is never included.
var value = apex.item('P20_PROGRESS_BAR').getValue();

// Show/Hide Methods
apex.item('P20_PROGRESS_BAR').show();
apex.item('P20_PROGRESS_BAR').hide();

/* The most important method here is the setValues method.
 * You can provide this method with 2 objects. The values, and the options objects 
 * The values object can contain the elements "percentage", "message", "color" and "duration".
 * The options object so far only contains the element "immediate", which defaults to false.
 */

// This is the same as the above setValue call
apexProgressBar('P20_PROGRESS_BAR').setValues({percentage: 20, message: "Loading...", duration: 1000});

// What we can also do is only change one of these values at a time. The other values are left the same.
apexProgressBar('P20_PROGRESS_BAR').setValues({message: "Loading..."});

// As opposed to the setValue function or dynamic action, this function also allows us to change the color of the progress bar
apexProgressBar('P20_PROGRESS_BAR').setValues({color: "red", duration: 100});    //could be helpful when showing an error

// Remember, successive calls to setValue(s) land the animations in a queue.
// To clear the queue and perform the setValues call immediately, use:
apexProgressBar('P20_PROGRESS_BAR').setValues({percentage: 40}, {immediate: true});

// More specific getter methods
var percentage = apexProgressBar('P20_PROGRESS_BAR').getPercentage();
var message    = apexProgressBar('P20_PROGRESS_BAR').getMessage();
var color      = apexProgressBar('P20_PROGRESS_BAR').getColor();

// To control the animation queue, we can use the following:
apexProgressBar('P20_PROGRESS_BAR').finish(); //goes immediately to the latest state of the queue
apexProgressBar('P20_PROGRESS_BAR').stop();   //stops the animation and empties the queue