Next is Public and Private
In this video we start thinking about hiding some information using Public and Private Access Control Modifiers. In ActionScript 3 there are a few types of Access control modified but we will focus for now on the two most common ones Public/Private and visit others in the future.
Video Transcript
00:00My application timeout now has a default time. I want to store that amount that seconds into memory
00:07So to do that, I'm going to create a new variable and I'm going to call it total seconds
00:13It's going to be a type of integer and as soon as our time all begins. I am going to set our total
00:19seconds to be that seconds, okay
00:23As we were working with our constructor we from this point on we want to tell every single variable that we create
00:30If we want the world to be able to see it or not and we're going to see right now what that means
00:35We're going to start with first the word private
00:37Now our constructor always will be public no matter what okay?
00:41It's really important because our constructor has to be public for our objects to be well
00:45It's just the rule
00:46But also just logically for our application to be able to build that out that object to be able to build that time
00:52And it needs to have access to the function that builds it out right because we're sending information to we're building that custom experience
01:00If our variable is private our app won't have access to it
01:05But if our variable was public, let's start public and let me put there just some well
01:11We're not going to put something in there because we're going to send it in our timeout
01:14So as soon as I call my town
01:15I'm going to send a 10 and I want to trace out the value that's in there and the way I could do
01:20That is I could just call my total seconds. I just created and
01:24The total seconds will be available to me because it's public
01:28We're not going to look into other differentiations at this point for now
01:32There's only public and there's only private and as we progress in our skill set gets more we feel more comfortable
01:38We're going to add a few other items
01:40So for now we have public and we have private now if I would type private what that would mean is that if I try
01:46To run my application again. It's going to tell me whoa careful here. You're not allowed to access this information
01:51All right a little error 11 78 so total seconds is not available anymore because it's private
01:58That's actually good because I don't really want users to be able to access directly my variables
02:03Because if I set a timeout and I'm doing all this logic inside
02:06I don't want someone coming and changing the amount of seconds
02:08Just whenever they feel like it because it could create bugs and it could break the experience
02:13You're going to see that a lot of times developers are going to work a little bit more than they you know
02:18You would think logically that they need to because they want to protect variables variables
02:22Arab is data right functions is actions and
02:26Variables we don't have any control over them. Well methods
02:29We do have control over them and what I'm calling methods is functions that belong to a specific object by knowing that
02:36What if we instead created a public function?
02:41that
02:43Would send us our get total
02:47seconds and
02:48It would send back an integer and I really would have to do in here is just set return total
02:54Seconds and the reason why I could do it in here is because private is to the world
02:59But while I'm inside of this class, I have access to everything in this class
03:03Okay, but what I'm saying private and the rest of the world can't see it anymore
03:07So by setting a get total seconds
03:09It enables me now to have the user a way to get that information without the user being capable of changing the information
03:17Because the user has no more access. They can't just go if this was public
03:21They could have just gone to our total seconds, right? They could just grab that total seconds
03:28And just decide right now that from now on it's going to be 20, right?
03:33We don't want the users to have access to that right? That's private at this point
03:37We only want to let them actually view the data. So to be able to let them view the data
03:41We just created that new get
03:44total seconds is
03:46Which is a function and it's not a variable anymore and then they could do whatever they want with the data that comes back
03:50Cuz they can't affect our time out from our timeout class. Let's see. We have a very little error
03:56So prior spelling error total second
04:02Type that in there total seconds if we run it one more time, we're gonna see that it's getting our total seconds
04:08So we've learned a lot of really critical things together. So because we know what variables are already we know what functions are
04:14all we're really added into the picture right now is that variables belong to the objects and
04:20functions belong to the objects as well and when they belong the front a variable will be called a
04:26Property and when a when a function is belongs to a class or to belongs an object
04:31It will be called it will be called a method