1 00:00:03,770 --> 00:00:08,240 In this lecture, we're going to be creating the game manager, which is going to control the flow between 2 00:00:08,240 --> 00:00:10,340 our quiz screen and our wind screen. 3 00:00:10,340 --> 00:00:13,040 And this will mark the end of our project. 4 00:00:13,840 --> 00:00:17,860 So let's go ahead and create our game manager over in the hierarchy. 5 00:00:17,860 --> 00:00:20,920 Lets right click and create a new empty object. 6 00:00:21,040 --> 00:00:27,520 I'm going to reset the transform and then rename the object to be the game manager and let's go ahead 7 00:00:27,520 --> 00:00:30,220 and create a new script in our scripts folder. 8 00:00:30,220 --> 00:00:35,200 So right click Create C-sharp script and call it the game manager. 9 00:00:35,830 --> 00:00:41,860 And you'll notice with this script it's been given a brand new icon, and that's because game managers 10 00:00:41,860 --> 00:00:43,450 are incredibly common. 11 00:00:43,450 --> 00:00:49,480 So Unity has kindly changed the icon for this type of script so that we can easily find it buried in 12 00:00:49,480 --> 00:00:50,590 our assets folder. 13 00:00:50,980 --> 00:00:56,020 Let's go ahead and drag our game manager script over to our game manager object and then we're going 14 00:00:56,020 --> 00:00:57,580 to go and open that up. 15 00:00:58,250 --> 00:01:03,500 Now before we worry about reloading levels and things like that, let's just set up the transitions 16 00:01:03,500 --> 00:01:06,740 between our quiz canvas and our win canvas. 17 00:01:06,890 --> 00:01:10,570 So let's go ahead and tidy up the comments above starts and update. 18 00:01:10,580 --> 00:01:14,480 But we are going to need both of these methods, so we'll leave them intact for now. 19 00:01:15,020 --> 00:01:17,630 Up at the top, we're going to need a few variables. 20 00:01:17,630 --> 00:01:23,180 We're going to need access to our quiz script so we can say quiz and we'll call it the quiz. 21 00:01:23,970 --> 00:01:26,430 And we need access to our end screen script. 22 00:01:26,430 --> 00:01:28,320 So we will call this the end screen. 23 00:01:29,010 --> 00:01:32,460 And in start, let's go ahead and find both these objects. 24 00:01:32,610 --> 00:01:37,890 So our quiz is going to be equal to find object of type quiz. 25 00:01:39,390 --> 00:01:45,150 And our end screen is going to be equal to find objects of type end screen. 26 00:01:46,480 --> 00:01:52,300 Next, we're going to want to toggle the visibility of these canvases so that our quiz canvas is visible 27 00:01:52,300 --> 00:01:55,180 when the game starts and our end screen is hidden. 28 00:01:55,270 --> 00:01:58,720 And then later on in the game's lifecycle, these will swap over. 29 00:01:58,960 --> 00:02:10,509 So also in start, let's say that our quiz game object dot set active equals true and our end screen 30 00:02:10,930 --> 00:02:15,400 game object dot set active equals false. 31 00:02:16,090 --> 00:02:23,010 So what this is doing is taking the game object itself and then changing its active state in the hierarchy. 32 00:02:23,020 --> 00:02:28,880 So if we jump back to unity, it's just like toggling the little flag next to the name up in the inspector. 33 00:02:28,900 --> 00:02:30,910 So if it's true, we can see it. 34 00:02:30,910 --> 00:02:32,890 And if it's false, it'll disappear. 35 00:02:33,280 --> 00:02:38,380 While we're here in our hierarchy, let's enable both our quiz canvas and our win canvas. 36 00:02:38,410 --> 00:02:43,480 It makes things look a bit messy, but that's okay because if we go ahead and hit play, then our game 37 00:02:43,480 --> 00:02:49,060 manager is going to sort everything out for us and it's going to enable our quiz canvas and disable 38 00:02:49,060 --> 00:02:50,200 our win canvas. 39 00:02:50,470 --> 00:02:55,960 Next, our game manager is going to want to toggle the states for our two canvases when the game ends. 40 00:02:56,200 --> 00:03:02,620 So back over in our script, we're going to do this in update and this is going to be your challenge. 41 00:03:02,740 --> 00:03:09,640 I would like you to check whether the game has been completed and if it has, then we want to disable 42 00:03:09,640 --> 00:03:13,110 the quiz canvas and enable the win canvas. 43 00:03:13,120 --> 00:03:15,820 So pause the video now and give that a go. 44 00:03:21,090 --> 00:03:21,570 Okay. 45 00:03:21,570 --> 00:03:22,530 Welcome back. 46 00:03:22,560 --> 00:03:26,640 So to check whether the game is completed, we're going to need an if statement. 47 00:03:26,850 --> 00:03:32,640 And if you recall in our quiz script, we have a public variable called is complete. 48 00:03:33,150 --> 00:03:37,710 And this was being set when the progress bar was completely filled. 49 00:03:38,160 --> 00:03:47,400 So if our game is complete, we want to take our quiz game object and change the set active to false. 50 00:03:48,480 --> 00:03:50,400 And we want to take our end screen. 51 00:03:50,700 --> 00:03:52,050 Dot game object. 52 00:03:52,230 --> 00:03:54,810 Dot set active to true. 53 00:03:55,980 --> 00:04:00,300 Finally, for this method, we're going to want a way of reloading our scene. 54 00:04:00,300 --> 00:04:06,450 If the player clicks the play again button and we can do this using the unity scene management system. 55 00:04:06,450 --> 00:04:10,380 So at the top of our script, let's add another using statement. 56 00:04:10,920 --> 00:04:15,990 And this time we're going to use unity engine dot scene management. 57 00:04:16,870 --> 00:04:20,740 We can then create a new method that we can attach to our button. 58 00:04:20,860 --> 00:04:26,800 So let's create a public void and we'll call this on replay level. 59 00:04:29,240 --> 00:04:30,950 And to reload the scene. 60 00:04:30,950 --> 00:04:38,840 We want the scene manager to load scene and in here we have a multitude of options and if we scroll 61 00:04:38,840 --> 00:04:45,110 through, we're going to use this option here where we pass in the scene, build index and to get the 62 00:04:45,110 --> 00:04:53,540 build index of the current scene, we can say scene manager dot get active scene dot build index. 63 00:04:54,410 --> 00:05:00,290 So this is getting the build index of the currently active scene and we're just telling the scene manager 64 00:05:00,290 --> 00:05:02,300 to load that scene again. 65 00:05:02,630 --> 00:05:07,910 That will refresh our quiz and all of our scores and allow the player to play the game again. 66 00:05:08,210 --> 00:05:15,290 So let's go ahead and save our game manager script, jump back into unity and on our win canvas we want 67 00:05:15,290 --> 00:05:22,220 to go to our replay button, scroll down and in our on click event we're going to add the plus icon. 68 00:05:23,120 --> 00:05:25,340 Drag over our game manager. 69 00:05:26,090 --> 00:05:32,630 And then in the dropdown we're going to select the game manager and then on replay level, now it's 70 00:05:32,630 --> 00:05:37,810 finally time to test everything out and check that everything our game is working correctly. 71 00:05:37,820 --> 00:05:39,770 So let's go ahead and hit play. 72 00:05:40,710 --> 00:05:45,960 And we find that after we've answered all of our questions, our windscreen is popping up and our quiz 73 00:05:45,960 --> 00:05:47,460 canvas is being hidden. 74 00:05:47,460 --> 00:05:50,220 But our score message has not been updated. 75 00:05:50,220 --> 00:05:53,310 And that is because we've forgotten to call the method that does that. 76 00:05:53,700 --> 00:05:57,090 But what we're hearing is at least double check our play again button. 77 00:05:57,270 --> 00:05:59,360 And the game does seem to reload. 78 00:05:59,370 --> 00:06:04,770 But we've also got a warning message down here and it's saying we've got a problem with our display 79 00:06:04,770 --> 00:06:06,690 answer on line 78. 80 00:06:06,690 --> 00:06:09,120 So let's look into both of those problems. 81 00:06:09,270 --> 00:06:16,500 Head over into our game manager script first, because when the game is completed, as well as setting 82 00:06:16,500 --> 00:06:24,750 our end screen to be active, we also want to take our end screen dot show final score that should update 83 00:06:24,750 --> 00:06:30,570 that text field for us to show us our final score and for the error that's showing up when we reload 84 00:06:30,570 --> 00:06:33,480 the game, let's head over to our quiz script. 85 00:06:33,720 --> 00:06:39,300 And the problem exists in our update method where we're currently checking to see if we should be loading 86 00:06:39,300 --> 00:06:40,470 an exit question. 87 00:06:40,470 --> 00:06:42,810 And if we are, then we need to get the next question. 88 00:06:42,960 --> 00:06:47,100 Otherwise we're going to be displaying the answer and setting the button state. 89 00:06:47,340 --> 00:06:52,740 And this error is popping up because on the very first update loop of the game, this statement is currently 90 00:06:52,740 --> 00:06:55,020 false and this statement is true. 91 00:06:55,020 --> 00:07:00,180 So we're trying to display an answer, but we haven't actually set a current question yet. 92 00:07:00,570 --> 00:07:06,180 Now this bug can take a little while to track down, but I found the quickest and easiest way to fix 93 00:07:06,180 --> 00:07:12,960 this problem is to go up to where we're creating our has answered early boolean check and just setting 94 00:07:12,960 --> 00:07:18,900 this to true to start with this means that on the very first loop, if we head back down to our update 95 00:07:18,900 --> 00:07:22,050 loop, this check is going to fail. 96 00:07:22,170 --> 00:07:24,690 So we're not going to try and display an answer. 97 00:07:24,690 --> 00:07:30,930 Then on the next update loop, this will be true and everything will work as intended while we're here. 98 00:07:30,930 --> 00:07:36,000 You may have also noticed during testing that when we answer the final question, rather than giving 99 00:07:36,000 --> 00:07:40,530 us time to check the answer, it just jumps straight to our windscreen. 100 00:07:40,860 --> 00:07:45,150 And this is to do with where we're setting our is complete flag. 101 00:07:45,150 --> 00:07:51,000 So we're currently doing it when we select the answer, which is automatically throwing us to that windscreen. 102 00:07:51,000 --> 00:07:54,330 So if instead we cut this out of here for now. 103 00:07:55,040 --> 00:08:00,980 And what I'm going to do is I'm going to pop it in my update loop when we check for a new question. 104 00:08:01,250 --> 00:08:05,750 So now when we answer the final question, we're going to wait for that timer to run down so we can 105 00:08:05,750 --> 00:08:06,800 review the answer. 106 00:08:06,950 --> 00:08:12,110 And then in update, it's going to try and load a new question, which isn't going to exist in our list, 107 00:08:12,110 --> 00:08:17,050 but we're going to catch that with our if statement we can say is complete to true. 108 00:08:17,060 --> 00:08:22,310 And then to avoid getting another question and potentially causing an error, let's just return out 109 00:08:22,310 --> 00:08:23,870 of our update loop early. 110 00:08:24,230 --> 00:08:30,620 Finally, before we test everything out for one last time, there's also another bug that you may see 111 00:08:30,830 --> 00:08:33,679 and it's again a null reference exception error. 112 00:08:33,679 --> 00:08:36,370 And this time is to do with the end screen. 113 00:08:36,380 --> 00:08:42,140 But since this bug can show up all over the place, let's tackle it on all of the scripts we've written. 114 00:08:42,289 --> 00:08:46,880 And the problem comes from finding objects in START. 115 00:08:47,180 --> 00:08:51,920 Now to explain this further, let's have a look at the Unity script execution order. 116 00:08:52,190 --> 00:08:56,990 We already know that START will be called when the game starts and before the update loop. 117 00:08:56,990 --> 00:09:02,630 But as you can see from this flowchart, there's also a few more options that are available even before 118 00:09:02,630 --> 00:09:03,380 start. 119 00:09:03,590 --> 00:09:07,190 And the method that we're interested in here is the awake method. 120 00:09:07,490 --> 00:09:12,410 Just like Start Awake is only ever called once for the lifetime of the game object. 121 00:09:12,410 --> 00:09:17,600 And it's good practice whenever we're finding objects in our scene or getting components set up for 122 00:09:17,600 --> 00:09:23,630 our scripts that we do these things in a wake because all of the scripts will run their awake method 123 00:09:23,630 --> 00:09:25,640 and then call their start methods. 124 00:09:25,940 --> 00:09:32,330 So if we jump back over into our script, what we're going to do is whenever we're finding objects in 125 00:09:32,330 --> 00:09:35,960 START, which is going to change our start method to awake. 126 00:09:36,230 --> 00:09:41,990 So in our end screen script, we're going to change start to awake so that our scorekeeper can be grabbed 127 00:09:41,990 --> 00:09:44,900 nice and early in our quiz script. 128 00:09:44,900 --> 00:09:50,240 We're doing some other stuff like setting up progress bars, but because these are related to the quiz 129 00:09:50,240 --> 00:09:53,540 script, it doesn't matter if these also happen in a week. 130 00:09:53,540 --> 00:09:57,770 So let's go and change our start method to awake in here as well. 131 00:09:58,860 --> 00:09:59,730 In Scorekeeper. 132 00:09:59,730 --> 00:10:04,750 We don't have a start method at all so we can leave that as is in our game manager. 133 00:10:04,770 --> 00:10:11,340 We're finding some objects of type and setting things to active, and this is a situation where a start 134 00:10:11,340 --> 00:10:13,590 and an awake method will come in useful. 135 00:10:13,800 --> 00:10:16,680 So above start, let's create an awake method. 136 00:10:20,000 --> 00:10:24,410 In a wake, we're going to cut and paste our finding objects of type. 137 00:10:25,610 --> 00:10:26,510 And then install it. 138 00:10:26,510 --> 00:10:29,510 We're going to set whether these objects are active or not. 139 00:10:30,110 --> 00:10:36,110 So with that aside on script execution order out of the way, let's go ahead and save all of our scripts 140 00:10:36,110 --> 00:10:37,640 and jump back into unity. 141 00:10:38,240 --> 00:10:39,890 Let's go ahead and hit play. 142 00:10:40,400 --> 00:10:43,850 We can once again see that our win canvas is being hidden. 143 00:10:44,180 --> 00:10:50,510 And if we go ahead and jump through our quiz very quickly, we'll find that our quiz canvas becomes 144 00:10:50,510 --> 00:10:55,130 hidden after answering the last question and our win canvas becomes active. 145 00:10:55,160 --> 00:11:01,850 Our score is correctly being updated and displayed, and if we go ahead and play again, then the game 146 00:11:01,850 --> 00:11:06,080 will reload and we'll get no errors at any stage during our game. 147 00:11:06,230 --> 00:11:10,750 So that now brings us to the end of the section and we now have a working game. 148 00:11:10,760 --> 00:11:15,920 The only thing left to do is to add as many questions as you want and give yourselves a big pat on the 149 00:11:15,920 --> 00:11:18,290 back for finishing your quiz master game.