1 00:00:01,090 --> 00:00:03,920 Let's keep building or Pig Game. 2 00:00:03,920 --> 00:00:04,860 And in this video, 3 00:00:04,860 --> 00:00:07,670 we're gonna be concerned with switching 4 00:00:07,670 --> 00:00:10,423 from one active player to another one. 5 00:00:11,970 --> 00:00:16,113 So as we already know, whenever the player rules are one, 6 00:00:17,000 --> 00:00:20,820 we will enter this else block, right? 7 00:00:20,820 --> 00:00:23,061 So when the dice is not a 1, 8 00:00:23,061 --> 00:00:26,460 then the current dice gets added to the current score. 9 00:00:26,460 --> 00:00:28,820 But if we happen to roll a 1, 10 00:00:28,820 --> 00:00:30,840 then we lose all our score 11 00:00:30,840 --> 00:00:34,920 and it is the next players round, all right? 12 00:00:34,920 --> 00:00:36,490 So in the previous lecture, 13 00:00:36,490 --> 00:00:40,790 we implemented this functionality of adding the dice 14 00:00:40,790 --> 00:00:42,670 to the current score only 15 00:00:42,670 --> 00:00:46,200 as the player number 0, okay? 16 00:00:46,200 --> 00:00:48,370 But now we need to make this work 17 00:00:48,370 --> 00:00:51,770 for both player number 0 and number 1. 18 00:00:51,770 --> 00:00:52,690 And so for that, 19 00:00:52,690 --> 00:00:55,210 we need to keep track of which player 20 00:00:55,210 --> 00:00:57,690 is actually the current player. 21 00:00:57,690 --> 00:00:58,850 And in order to do that, 22 00:00:58,850 --> 00:01:01,940 we actually need to keep track of which player 23 00:01:01,940 --> 00:01:05,280 is actually the active player in a moment 24 00:01:05,280 --> 00:01:07,270 that the dice was rolled. 25 00:01:07,270 --> 00:01:09,690 So basically we need to know which player 26 00:01:09,690 --> 00:01:11,990 is right now playing. 27 00:01:11,990 --> 00:01:13,770 And with right now I mean, 28 00:01:13,770 --> 00:01:17,350 whenever the button is clicked, all right? 29 00:01:17,350 --> 00:01:19,420 So we will create another variable, 30 00:01:19,420 --> 00:01:21,560 which will hold exactly that. 31 00:01:21,560 --> 00:01:22,970 So it will hold 0, 32 00:01:22,970 --> 00:01:25,900 if the current player is player 0 33 00:01:25,900 --> 00:01:27,360 and it will hold 1, 34 00:01:27,360 --> 00:01:31,093 if the active player is player number 1. 35 00:01:33,490 --> 00:01:38,490 So let active player. 36 00:01:38,870 --> 00:01:41,820 And since we start with the first player, 37 00:01:41,820 --> 00:01:43,750 we set it to 0, 38 00:01:43,750 --> 00:01:47,230 because remember that player number 1 is player 0 39 00:01:47,230 --> 00:01:51,860 and player 2 is here in our code player number 1. 40 00:01:51,860 --> 00:01:55,600 And in fact, let me explain you right away, why that is. 41 00:01:55,600 --> 00:01:58,400 So the reason is that we will store the scores 42 00:01:58,400 --> 00:02:01,560 of both players in an array. 43 00:02:01,560 --> 00:02:02,773 So let me do that here. 44 00:02:03,990 --> 00:02:08,780 So let or actually const, because it's an array. 45 00:02:08,780 --> 00:02:12,530 So const scores equals an array, 46 00:02:12,530 --> 00:02:16,713 which will start with 0 points for both sides. 47 00:02:17,560 --> 00:02:21,180 And so these scores are actually the final scores. 48 00:02:21,180 --> 00:02:24,100 So the big scores, which accumulate, 49 00:02:24,100 --> 00:02:25,983 let me show that to you in the demo. 50 00:02:26,960 --> 00:02:30,390 So that's these big scores here. 51 00:02:30,390 --> 00:02:32,010 So these are the current scores, 52 00:02:32,010 --> 00:02:34,310 and these are, let's say the total scores 53 00:02:34,310 --> 00:02:36,470 that keep accumulating, right? 54 00:02:36,470 --> 00:02:41,270 And so we are storing these two scores here in an array. 55 00:02:41,270 --> 00:02:43,660 And remember that the array is zero-based 56 00:02:43,660 --> 00:02:45,610 and so the score of player number 1 57 00:02:45,610 --> 00:02:47,590 will be here at position 0, 58 00:02:47,590 --> 00:02:51,110 and the score of player two will be at position 1. 59 00:02:51,110 --> 00:02:53,150 And so that's why it will be handy 60 00:02:53,150 --> 00:02:55,660 to have the activePlayer variable here, 61 00:02:55,660 --> 00:02:59,260 also set to 0 and 1, okay? 62 00:02:59,260 --> 00:03:01,900 And we will see that in action actually, 63 00:03:01,900 --> 00:03:06,610 in the next lecture, where we will hold the scores, 64 00:03:06,610 --> 00:03:10,040 but for now knowing which is the active player 65 00:03:10,040 --> 00:03:11,870 is going to be important 66 00:03:11,870 --> 00:03:15,180 to actually display the current score here 67 00:03:15,180 --> 00:03:16,890 for the current player 68 00:03:16,890 --> 00:03:20,610 and not just always for player number 0. 69 00:03:20,610 --> 00:03:24,200 So instead of manipulating the element of player 0, 70 00:03:24,200 --> 00:03:26,660 so the current score of player 0, 71 00:03:26,660 --> 00:03:31,230 let's actually select the element dynamically, okay? 72 00:03:31,230 --> 00:03:32,580 So let me show that to you. 73 00:03:33,840 --> 00:03:37,210 So we will actually now do the selection right here, 74 00:03:37,210 --> 00:03:41,213 document. and actually let's use getElementById. 75 00:03:42,922 --> 00:03:45,270 And then here we need the class name. 76 00:03:45,270 --> 00:03:49,240 So the class name is gonna be either current O, 77 00:03:49,240 --> 00:03:54,210 for player 0, or current 1 for player 1. 78 00:03:54,210 --> 00:03:57,530 And so maybe now you start to see once more 79 00:03:57,530 --> 00:04:00,940 why we use the active player as 0 or 1, 80 00:04:00,940 --> 00:04:03,740 because now we can use that variable 81 00:04:03,740 --> 00:04:07,763 to basically build these collapse names, okay? 82 00:04:08,760 --> 00:04:10,520 So when it's player 0, 83 00:04:10,520 --> 00:04:15,520 we will then end up with current--0 84 00:04:15,760 --> 00:04:16,770 and if it's 1, 85 00:04:16,770 --> 00:04:19,440 we will end up with current--1 86 00:04:19,440 --> 00:04:21,540 because that's gonna be the active player. 87 00:04:23,510 --> 00:04:27,430 So what I just said is to do this. 88 00:04:27,430 --> 00:04:28,387 So current-- 89 00:04:31,180 --> 00:04:36,180 and then the number of the active player, okay? 90 00:04:38,550 --> 00:04:40,090 And so now on this, 91 00:04:40,090 --> 00:04:42,740 we will get the text content 92 00:04:42,740 --> 00:04:46,243 and set it to the current score, okay? 93 00:04:50,280 --> 00:04:54,050 So again, this 1 here will always set the text content 94 00:04:54,050 --> 00:04:56,410 on player number 0, 95 00:04:56,410 --> 00:04:58,860 but here we do instead select 96 00:04:58,860 --> 00:05:02,840 the score element dynamically based on which 97 00:05:02,840 --> 00:05:05,163 is the active player right now, okay? 98 00:05:08,450 --> 00:05:10,450 So this is a very handy trick 99 00:05:10,450 --> 00:05:14,523 of building the ID name like this dynamically. 100 00:05:16,580 --> 00:05:19,530 Now here, when we switch the player, 101 00:05:19,530 --> 00:05:22,820 we of course will then need to change that value 102 00:05:22,820 --> 00:05:25,713 from zero to one or from one to zero. 103 00:05:26,720 --> 00:05:28,560 So let's do that here. 104 00:05:28,560 --> 00:05:33,560 So essentially switching the next player, 105 00:05:33,870 --> 00:05:36,240 that means to change that value. 106 00:05:36,240 --> 00:05:38,320 So activePlayer, 107 00:05:38,320 --> 00:05:42,050 and now here, let's not use again, the turnery operator. 108 00:05:42,050 --> 00:05:46,320 So we can say if the activePlayer is 0, 109 00:05:48,700 --> 00:05:51,370 then we want the new activePlayer to be 1 110 00:05:52,320 --> 00:05:54,980 and else it should be 0. 111 00:05:54,980 --> 00:05:58,180 All right, does that make sense? 112 00:05:58,180 --> 00:06:02,490 So essentially we are reassigning the active player here 113 00:06:02,490 --> 00:06:06,320 and we're checking whether right now it is player 0. 114 00:06:06,320 --> 00:06:10,910 So if it is then here the result of this whole operator, 115 00:06:10,910 --> 00:06:13,210 so which again is all of this, 116 00:06:13,210 --> 00:06:15,000 then the result will be 1. 117 00:06:15,000 --> 00:06:19,000 And so then activePlayer will be equal to 1, 118 00:06:19,000 --> 00:06:22,100 but if this is false here, 119 00:06:22,100 --> 00:06:24,480 so if the player is actually 1, 120 00:06:24,480 --> 00:06:27,830 well then the active player will become 0. 121 00:06:27,830 --> 00:06:30,160 And so essentially this allows us to switch 122 00:06:30,160 --> 00:06:32,200 from zero to 1. 123 00:06:32,200 --> 00:06:37,200 All right, so I think this would actually work already. 124 00:06:38,430 --> 00:06:39,263 So this is the demo, 125 00:06:39,263 --> 00:06:41,070 this is the real game. 126 00:06:41,070 --> 00:06:44,260 Let's just make sure that it works and reload it. 127 00:06:44,260 --> 00:06:45,870 And now as we roll the dice, 128 00:06:45,870 --> 00:06:48,650 remember that we are player number 0 right now. 129 00:06:48,650 --> 00:06:49,483 So this one. 130 00:06:50,790 --> 00:06:55,750 So 3 gets added to 0 is 3 and 7, 131 00:06:55,750 --> 00:06:57,670 so this works right now. 132 00:06:57,670 --> 00:07:01,840 Three, let's wait for a one so that we can switch the player 133 00:07:01,840 --> 00:07:03,343 and see what happens then. 134 00:07:07,600 --> 00:07:08,760 Okay. 135 00:07:08,760 --> 00:07:10,250 So now we're all the one. 136 00:07:10,250 --> 00:07:13,040 And so now we should be player number 1. 137 00:07:13,040 --> 00:07:15,860 So and essentially player 2. 138 00:07:15,860 --> 00:07:18,040 And so now when we roll the dice again, 139 00:07:18,040 --> 00:07:21,810 the new score should appear down here, right? 140 00:07:21,810 --> 00:07:24,380 Because this here is current 1. 141 00:07:24,380 --> 00:07:26,660 So this element here is the current 1 142 00:07:26,660 --> 00:07:29,510 that we just defined previously 143 00:07:30,900 --> 00:07:34,520 and indeed it works. 144 00:07:34,520 --> 00:07:36,410 So something happened here, 145 00:07:36,410 --> 00:07:39,440 but of course we need to reset the current score. 146 00:07:39,440 --> 00:07:42,240 So the current score was just for this player, 147 00:07:42,240 --> 00:07:44,080 but now we edit that for 148 00:07:44,080 --> 00:07:47,130 to the current score of the previous round. 149 00:07:47,130 --> 00:07:48,720 So as we switch the player, 150 00:07:48,720 --> 00:07:53,170 we also need to reset the current score, okay? 151 00:07:53,170 --> 00:07:56,620 So the logic of the active player is already working, 152 00:07:56,620 --> 00:08:00,140 but we still need to reset the current score. 153 00:08:00,140 --> 00:08:03,620 Also, you see that visually nothing changed yet. 154 00:08:03,620 --> 00:08:07,290 So in the real game, when the player is switched, 155 00:08:07,290 --> 00:08:09,250 this side here becomes white 156 00:08:09,250 --> 00:08:12,260 and so the background kind of changes there. 157 00:08:12,260 --> 00:08:15,200 Oh, and another thing is that this current score here 158 00:08:15,200 --> 00:08:19,800 should also then be set back to 0 again, okay? 159 00:08:19,800 --> 00:08:21,730 So basically the previous player 160 00:08:21,730 --> 00:08:26,030 should have its current score here visibly set to 0. 161 00:08:27,110 --> 00:08:29,210 So let me just tell you what happens here. 162 00:08:30,920 --> 00:08:32,743 When we switch to another player, 163 00:08:33,607 --> 00:08:35,007 so you see the current score 164 00:08:37,070 --> 00:08:38,110 and now there's a 1 165 00:08:38,110 --> 00:08:40,820 and so now this side here became white 166 00:08:40,820 --> 00:08:42,030 and then of course the current 167 00:08:42,030 --> 00:08:44,720 of the other player became 0. 168 00:08:44,720 --> 00:08:47,480 So let's first take care of that logic 169 00:08:47,480 --> 00:08:49,140 of changing the values 170 00:08:49,140 --> 00:08:52,363 and then I will show you how we change the background here. 171 00:08:54,240 --> 00:08:55,560 So let's go back. 172 00:08:55,560 --> 00:08:57,530 And the first thing that we need to do 173 00:08:57,530 --> 00:09:00,000 is to set the current score back to 0. 174 00:09:01,610 --> 00:09:05,770 So current score back to 0, 175 00:09:06,765 --> 00:09:11,470 and then we need to set the text content back to 0, okay? 176 00:09:11,470 --> 00:09:16,470 So basically of the active player before we switch it. 177 00:09:16,750 --> 00:09:20,200 So for example, player 0 was playing 178 00:09:20,200 --> 00:09:22,130 and then we switched to player 1, 179 00:09:22,130 --> 00:09:23,640 but before we do that switch, 180 00:09:23,640 --> 00:09:25,720 we need to change the current score 181 00:09:25,720 --> 00:09:28,700 of player 0 back to 0. 182 00:09:28,700 --> 00:09:33,700 So we need to do that here before we do the switch, okay? 183 00:09:33,980 --> 00:09:36,993 So basically what we do is the same as this, 184 00:09:39,290 --> 00:09:43,183 but we simply set it to 0, okay. 185 00:09:45,020 --> 00:09:46,840 So we're selecting the current player, 186 00:09:46,840 --> 00:09:49,360 which at this point is still 0 187 00:09:49,360 --> 00:09:52,530 and then we set his textContent to 0 188 00:09:52,530 --> 00:09:56,420 and then we switch from zero to one, okay? 189 00:09:56,420 --> 00:09:59,930 And actually we can also set the current score to 0 here, 190 00:09:59,930 --> 00:10:01,430 but that doesn't really matter 191 00:10:01,430 --> 00:10:04,793 because the current score is not bound to any player. 192 00:10:05,880 --> 00:10:09,223 So saving it, now let's try again. 193 00:10:11,310 --> 00:10:13,640 So all of this is still working, 194 00:10:13,640 --> 00:10:16,023 but let's wait what happens on the one? 195 00:10:20,050 --> 00:10:23,190 So that's a lot of points here, okay. 196 00:10:23,190 --> 00:10:27,050 So the current score is back to 0 here 197 00:10:27,050 --> 00:10:28,400 and now watch what happens 198 00:10:29,330 --> 00:10:32,970 and yeah, nice, that's working now. 199 00:10:32,970 --> 00:10:36,120 So now the actual current score variable 200 00:10:36,120 --> 00:10:38,080 was also set back to 0 201 00:10:38,080 --> 00:10:43,080 and so 6 plus 0 now on player number 1 is 6. 202 00:10:43,910 --> 00:10:47,240 So as we keep doing that, it keeps adding here 203 00:10:47,240 --> 00:10:50,513 and now we're back to player number 0, so this one. 204 00:10:53,270 --> 00:10:55,010 Then I wrote another one right away 205 00:10:55,010 --> 00:10:58,593 and so we switched to this player back again immediately. 206 00:10:59,700 --> 00:11:03,270 But you see that the logic here is already working. 207 00:11:03,270 --> 00:11:07,130 Now, the only thing that's left to do is that visual change. 208 00:11:07,130 --> 00:11:12,130 So putting that white background here on this other player. 209 00:11:12,900 --> 00:11:16,223 So let me show you in the HTML, how that works. 210 00:11:18,090 --> 00:11:22,620 And so basically the player that is active 211 00:11:22,620 --> 00:11:24,900 has this whole section here 212 00:11:24,900 --> 00:11:28,940 with the player--active class. 213 00:11:28,940 --> 00:11:31,380 So you see that this first section, 214 00:11:31,380 --> 00:11:34,360 which is for player 0 right now has this class 215 00:11:34,360 --> 00:11:37,810 because player 0 is always the first player. 216 00:11:37,810 --> 00:11:40,370 But then as we switch to the other player, 217 00:11:40,370 --> 00:11:44,160 we want to remove that class from here 218 00:11:44,160 --> 00:11:47,720 and basically put it here on the other player. 219 00:11:47,720 --> 00:11:50,250 Okay, so let's do that. 220 00:11:50,250 --> 00:11:51,083 And as always, 221 00:11:51,083 --> 00:11:54,137 we will start by selecting these two players. 222 00:11:54,137 --> 00:11:56,930 And this time is actually a class. 223 00:11:56,930 --> 00:12:00,523 So player 0 class and player 1 class. 224 00:12:01,740 --> 00:12:06,453 So let's do that here and do that as the first. 225 00:12:07,340 --> 00:12:11,793 So const player 0 element, 226 00:12:13,450 --> 00:12:16,243 document.querySelector. 227 00:12:17,090 --> 00:12:20,093 And now we need the dot for the class name, 228 00:12:21,350 --> 00:12:23,223 so that's player--1. 229 00:12:24,170 --> 00:12:25,390 And I'm just copying it here, 230 00:12:25,390 --> 00:12:26,393 I'm too lazy. 231 00:12:29,050 --> 00:12:31,850 And this 1 here is actually player 0, 232 00:12:31,850 --> 00:12:35,540 so 0 and 1 right here. 233 00:12:35,540 --> 00:12:39,300 And now let's actually change their class names. 234 00:12:39,300 --> 00:12:44,300 So the player active class, so down here. 235 00:12:44,360 --> 00:12:45,193 And for that, 236 00:12:45,193 --> 00:12:47,630 I will now show you yet another method 237 00:12:47,630 --> 00:12:50,573 that's available on the class list property. 238 00:12:52,896 --> 00:12:55,290 Well actually let's start typing first. 239 00:12:55,290 --> 00:12:58,027 So player0Element.Classlist, 240 00:13:01,030 --> 00:13:04,990 and we already saw the remove method, 241 00:13:04,990 --> 00:13:06,590 we saw the add method, 242 00:13:06,590 --> 00:13:09,290 but now I will show you the toggle method. 243 00:13:09,290 --> 00:13:11,250 So we will use toggle now. 244 00:13:11,250 --> 00:13:13,080 And what toggle will do is that 245 00:13:13,080 --> 00:13:16,270 it will add the class if it is not there 246 00:13:16,270 --> 00:13:19,870 and if it is there, it will remove it, okay. 247 00:13:19,870 --> 00:13:21,730 So we could do that manually also 248 00:13:21,730 --> 00:13:24,110 by checking if the class is there 249 00:13:24,110 --> 00:13:26,500 and only removing it if it is, 250 00:13:26,500 --> 00:13:30,290 but using toggle takes that work away from us. 251 00:13:30,290 --> 00:13:32,990 So actually we could have used this toggle method 252 00:13:32,990 --> 00:13:35,850 in the previous project of the popup, 253 00:13:35,850 --> 00:13:36,683 but back then, 254 00:13:36,683 --> 00:13:39,920 I actually wanted to show you the contains method. 255 00:13:39,920 --> 00:13:41,570 Remember that? 256 00:13:41,570 --> 00:13:45,203 But now again, we will use toggle here because it is easier. 257 00:13:46,520 --> 00:13:51,520 And so now we simply have to add this player active class 258 00:13:51,790 --> 00:13:55,070 or actually to toggle it. 259 00:13:55,070 --> 00:13:58,130 So if we do that on both then it will work 260 00:14:02,400 --> 00:14:07,400 because on player 0 it will remove the class if it's there 261 00:14:08,200 --> 00:14:10,140 and if it's not it will add it. 262 00:14:10,140 --> 00:14:12,820 And the same thing on the other player. 263 00:14:12,820 --> 00:14:15,890 And since we start with the player active class 264 00:14:15,890 --> 00:14:17,523 on only one element, 265 00:14:18,530 --> 00:14:20,820 so only on player 0 here, 266 00:14:20,820 --> 00:14:23,030 then toggling both at the same time 267 00:14:23,030 --> 00:14:25,180 will ensure that it's only ever 268 00:14:25,180 --> 00:14:28,130 on one of the elements at once. 269 00:14:28,130 --> 00:14:31,690 So let's now check that out 270 00:14:32,600 --> 00:14:34,400 just to make sure we load it here 271 00:14:35,640 --> 00:14:36,823 and let's wait for it. 272 00:14:42,240 --> 00:14:45,480 It's taking a lot of time and yes, 273 00:14:45,480 --> 00:14:47,360 so we switched the active player 274 00:14:47,360 --> 00:14:49,623 and now it's also nicely visible. 275 00:14:51,840 --> 00:14:55,100 And yes, we changed it back as well 276 00:14:55,100 --> 00:14:59,640 and so that works beautifully great job. 277 00:14:59,640 --> 00:15:02,600 And now basically the only thing that's missing 278 00:15:02,600 --> 00:15:04,930 to actually make this game work 279 00:15:04,930 --> 00:15:07,300 is to hold the current score. 280 00:15:07,300 --> 00:15:10,813 And so that is gonna be the topic of the next video.