1 00:00:01,420 --> 00:00:05,890 We can now show a Google map on the screen, which is great, but before we move on and start showing 2 00:00:05,890 --> 00:00:08,500 the markers, there's one last little thing I want to mention. 3 00:00:08,980 --> 00:00:11,410 I want to focus on the index stats file right now. 4 00:00:11,780 --> 00:00:13,380 I want to point out something inside of here. 5 00:00:13,480 --> 00:00:16,059 This is going to seem like a really strange thing to point out. 6 00:00:16,059 --> 00:00:17,620 Nonetheless, I just want to mention it. 7 00:00:18,290 --> 00:00:20,060 Let's just take a look at a diagram. 8 00:00:20,090 --> 00:00:22,990 I think you'll start to understand what I'm going to be talking about here. 9 00:00:23,510 --> 00:00:24,630 OK, so quick diagram. 10 00:00:25,360 --> 00:00:25,700 All right. 11 00:00:25,720 --> 00:00:27,220 So this is kind of a crazy diagram. 12 00:00:27,220 --> 00:00:33,870 Its purpose is to try to show all the different things that we can effectively do inside the index file. 13 00:00:34,300 --> 00:00:37,480 And I know that's weird to say, but let's just kind of walk to the diagram step by step. 14 00:00:37,870 --> 00:00:40,330 It's going to zoom in a little bit here and go up to the top. 15 00:00:41,400 --> 00:00:46,980 So inside of our index doctor's file, we've got an important statement for our company class now. 16 00:00:46,990 --> 00:00:51,850 We currently have that commented out, but we could very easily uncommented with our company class. 17 00:00:52,080 --> 00:00:55,440 We have two things that we can effectively do with it. 18 00:00:56,010 --> 00:00:58,230 We can use it to create a new instance of a company. 19 00:00:58,860 --> 00:01:02,940 And then with that instance of a company, we can reference its company name, catch phrase, latitude, 20 00:01:02,940 --> 00:01:03,510 longitude. 21 00:01:04,680 --> 00:01:06,840 Likewise, we've got the user class as well. 22 00:01:07,840 --> 00:01:10,780 It's currently commented out, but whatever we can, easily uncommented. 23 00:01:11,930 --> 00:01:16,970 With the user class, we can create a new instance of it or then reference that instances named latitude 24 00:01:16,970 --> 00:01:17,650 and longitude. 25 00:01:18,170 --> 00:01:23,780 So I'm just trying to describe like the total surface area of what we can do in Sibat index dots file 26 00:01:23,780 --> 00:01:24,250 right now. 27 00:01:24,600 --> 00:01:27,390 And so that's basically what we can do with the company and the user. 28 00:01:27,890 --> 00:01:32,090 Now, they're technically are other methods available to us, like, you know, the name properties, 29 00:01:32,090 --> 00:01:34,880 a string that has like a two uppercase method and so on. 30 00:01:35,160 --> 00:01:39,980 I'm just trying to write out or diagram out all the different things that we've added into our application 31 00:01:39,980 --> 00:01:42,080 that's specific to our application. 32 00:01:43,060 --> 00:01:47,660 So in other words, the surface area of the company and the user classes is quite small. 33 00:01:48,460 --> 00:01:50,760 Let's now start to think about that map we just created. 34 00:01:50,770 --> 00:01:52,840 However, I'm going to zoom back out just a little bit. 35 00:01:53,710 --> 00:01:55,960 So in the last video, we created that Google map, right. 36 00:01:56,560 --> 00:02:00,790 So we said right here, we said new Google Maps, Maps, dot map. 37 00:02:01,240 --> 00:02:03,820 This creates an instance of a map right here. 38 00:02:03,820 --> 00:02:07,000 We could technically assign the results of that to a variable. 39 00:02:08,300 --> 00:02:09,080 Like so. 40 00:02:10,130 --> 00:02:14,990 And then down here, we could write out a map and try to call a bunch of different methods attached 41 00:02:14,990 --> 00:02:16,140 to that Google map we created. 42 00:02:16,160 --> 00:02:20,300 So if I put a dot right there, I'll see all the different methods that are attached to a map. 43 00:02:20,770 --> 00:02:25,880 So I see add listener Binta changed fit bounds, get get bounce, all those different things. 44 00:02:25,880 --> 00:02:29,000 Those are all different methods we actually saw inside the type definition file. 45 00:02:29,330 --> 00:02:32,840 So another way of seeing all those different methods would once again be to command. 46 00:02:32,840 --> 00:02:36,710 Click on map right there and you'll see all those same functions listed out right here. 47 00:02:36,740 --> 00:02:40,040 These are all functions that belong to that instance of a map. 48 00:02:40,850 --> 00:02:43,190 And so those are what these boxes all represent. 49 00:02:43,190 --> 00:02:44,250 Size diagram right here. 50 00:02:44,270 --> 00:02:48,480 So we've got methods like Set Zoom, so that center set street view and so on. 51 00:02:49,160 --> 00:02:50,360 So why is this relevant? 52 00:02:51,020 --> 00:02:54,560 Well, this is going to seem like a weird thing, but I just want to point it out. 53 00:02:55,260 --> 00:02:59,950 These are all methods that we have exposed inside of our index file. 54 00:03:00,410 --> 00:03:06,080 So if another engineer started to come into our project, they could look at that map variable and say, 55 00:03:06,290 --> 00:03:09,020 oh, hey, look at these cool methods, attach the map. 56 00:03:09,230 --> 00:03:11,640 You know what I feel like, just starting to call them. 57 00:03:12,140 --> 00:03:17,570 So another engineer might come into our project, start calling the methods associated with that map 58 00:03:17,570 --> 00:03:20,510 and very easily break our application. 59 00:03:21,080 --> 00:03:22,880 I know that sounds strange. 60 00:03:22,880 --> 00:03:23,750 I know that's weird. 61 00:03:23,750 --> 00:03:26,060 Like, that's the job of Google Maps, right? 62 00:03:26,090 --> 00:03:28,890 Google Maps is here to expose all these different methods. 63 00:03:29,540 --> 00:03:35,480 My only point is that you and I, as the sole developers of this application, have not vetted these 64 00:03:35,480 --> 00:03:35,840 methods. 65 00:03:35,840 --> 00:03:40,460 We haven't sat down and said, oh, yeah, if you call these things, our application is going to continue 66 00:03:40,460 --> 00:03:41,620 to work perfectly. 67 00:03:41,990 --> 00:03:42,880 We didn't do that. 68 00:03:43,340 --> 00:03:48,740 So in theory, if someone started to call these methods, it might horribly break our application. 69 00:03:50,200 --> 00:03:56,920 Again, I know this sounds like a stretch, but let me just make a suggestion, maybe if we found out 70 00:03:56,920 --> 00:04:04,030 a way to limit other engineers access to these methods right here, maybe that would just slightly decrease 71 00:04:04,030 --> 00:04:06,860 the chances of our application breaking horribly. 72 00:04:07,570 --> 00:04:08,980 So here's what I'm going to suggest. 73 00:04:09,930 --> 00:04:16,709 Maybe we start to like firm up or limit the number of things we can do inside the index file, maybe 74 00:04:16,709 --> 00:04:22,890 we say the only things you can do inside of this file is create a new company, reference its properties, 75 00:04:23,310 --> 00:04:29,910 create a new user, reference its properties, and then maybe we should create a new class called MAP, 76 00:04:29,940 --> 00:04:31,830 like our own custom map class. 77 00:04:33,140 --> 00:04:38,720 And this custom map class can be used to create a new instance of a Google map, so this right here 78 00:04:39,200 --> 00:04:41,590 will create a new instance of a map, to be precise. 79 00:04:41,600 --> 00:04:44,330 And during that process, we can create a new instance of a Google map. 80 00:04:44,810 --> 00:04:50,600 And also on that map class, we can add a method called add marker, and we'll use that function right 81 00:04:50,600 --> 00:04:55,730 there to achieve our original goal, this application of showing a marker for user and company on the 82 00:04:55,730 --> 00:04:56,480 actual map. 83 00:04:57,420 --> 00:05:01,050 So, again, this class right here, you and I are going to create this is like maybe a better name 84 00:05:01,050 --> 00:05:02,970 for it to be like custom map like so. 85 00:05:03,970 --> 00:05:09,400 So then wrapped up inside this class, we will have some logic to create a Google map. 86 00:05:10,160 --> 00:05:16,220 And the important thing here is that that Google map and all of its associated dangerous functions and 87 00:05:16,220 --> 00:05:21,120 methods right here will not be easily exposed inside of our index file. 88 00:05:21,680 --> 00:05:27,140 And so if another engineer came into our project, they can't just open up that inducts file and start 89 00:05:27,140 --> 00:05:29,810 calling random methods on the Google map. 90 00:05:30,330 --> 00:05:32,270 Instead, we've hidden all those methods. 91 00:05:32,510 --> 00:05:38,660 We've wrapped them all up and taken them away from engineers and hidden them behind this facade of sorts 92 00:05:38,900 --> 00:05:41,950 or this kind of like black box of custom map. 93 00:05:42,350 --> 00:05:46,340 And the only thing you can do with custom map is create a new map and add a marker to it. 94 00:05:47,490 --> 00:05:52,320 Again, I know this sounds like a stretch, but the whole idea here is that if we have a program where 95 00:05:52,320 --> 00:05:58,110 these are like the only things you can do, chances are it's going to be way more challenging for people 96 00:05:58,110 --> 00:06:00,480 to come into our app and start to break things. 97 00:06:01,440 --> 00:06:03,030 All right, so let's take a quick pause right here. 98 00:06:03,210 --> 00:06:09,120 When we come back, the next video, we're going to start to extract this logic to create a Google map 99 00:06:09,120 --> 00:06:11,610 right here into a new class. 100 00:06:11,970 --> 00:06:17,130 And once again, this logic to create a Google map is going to wrap up all that stuff or give me our 101 00:06:17,130 --> 00:06:22,380 new class is going to wrap up the Google map and try to hide its existence from other engineers so they 102 00:06:22,380 --> 00:06:24,510 can't accidentally break our application. 103 00:06:25,370 --> 00:06:28,100 All right, so quick pause right here, take care of that in the next video.