1 00:00:01,490 --> 00:00:07,070 Come back again in this lesson we're going to talk about the control flow in swift but she's essentially 2 00:00:07,070 --> 00:00:13,970 using conditional statements switches for loops of wire loops and something else that's called a repeat 3 00:00:14,030 --> 00:00:19,690 loop which is very similar to a do while in Objective-C and other programming languages. 4 00:00:19,880 --> 00:00:22,500 So let's go ahead and have a quick look. 5 00:00:22,700 --> 00:00:25,350 This is going to be one of our easier lessons. 6 00:00:25,380 --> 00:00:31,400 So I'm going to make it in let's make a playground for it because you know we can alternate between 7 00:00:31,400 --> 00:00:33,130 them a playground. 8 00:00:33,170 --> 00:00:38,750 And in my playground I'm going to say this is control flow. 9 00:00:39,620 --> 00:00:40,280 All right. 10 00:00:40,340 --> 00:00:47,780 So the first thing that you want to do is this I want to say where my ends is five and then I want to 11 00:00:47,780 --> 00:00:58,060 say if my index is four then do something else do something else. 12 00:00:58,160 --> 00:01:04,580 So the only thing that's different here is that you don't need to have practices around your condition. 13 00:01:04,610 --> 00:01:08,570 Even though you could which is something I'm really used to do it. 14 00:01:08,630 --> 00:01:12,990 I do the fact it would Qantas's around brackets around my condition. 15 00:01:13,220 --> 00:01:14,510 So that's one thing. 16 00:01:14,510 --> 00:01:17,940 The other thing is you must have curly brackets. 17 00:01:18,050 --> 00:01:24,320 So you know Objective-C and other programming language languages the immediate line after that if or 18 00:01:24,330 --> 00:01:27,870 the else doesn't have to have a carefully bracket around it. 19 00:01:28,010 --> 00:01:31,010 But in strafed you must have curly brackets. 20 00:01:31,400 --> 00:01:37,790 So that's about that whatever you used to do with IF statements before you can do it like this in here. 21 00:01:37,790 --> 00:01:40,690 The other thing is using a switch. 22 00:01:41,100 --> 00:01:48,530 So for a switch I'm going to say switch and I want to switch my ends and then like always are if it 23 00:01:48,530 --> 00:01:53,950 is one print purines are one. 24 00:01:54,170 --> 00:01:56,270 And if it is difficult to break. 25 00:01:56,840 --> 00:02:02,240 So you would only use break in cases where you don't want anything to happen. 26 00:02:02,240 --> 00:02:04,960 For instance I want to say chase two. 27 00:02:05,300 --> 00:02:07,360 I don't care about whatever is inside it. 28 00:02:07,370 --> 00:02:14,330 I use break otherwise you don't need to have a break in each case like what we had in Objective-C because 29 00:02:14,330 --> 00:02:15,910 you don't need to have the same columns. 30 00:02:15,910 --> 00:02:19,570 I'm just adding them because I'm used to that system. 31 00:02:19,570 --> 00:02:23,930 Then next thing you are talking about is a form which is a very simple thing. 32 00:02:24,230 --> 00:02:33,230 If you remember the objective c it was four in and I 0 0 is smarter than 10 plus plus so on and so forth 33 00:02:33,650 --> 00:02:43,430 in Strief that is written like these four are in the zero to 10 and that's about that. 34 00:02:43,430 --> 00:02:49,090 So if I say print now if I want to print the value of all right. 35 00:02:49,080 --> 00:02:57,410 In fact I could say that since to pollution that we talked about earlier on and knife fight execute 36 00:02:57,410 --> 00:02:57,910 this 37 00:03:02,930 --> 00:03:10,760 it will actually say up 11 times is running sprinting 0 to 10. 38 00:03:11,060 --> 00:03:19,460 If you don't want to include 10 if you mean a smaller or then you can say or or just a smaller you can 39 00:03:19,460 --> 00:03:25,420 say four in zero dot dot and then a smaller sign. 40 00:03:25,580 --> 00:03:32,870 So now this will happen only 10 times zero to 9 as you would expect in terms of the syntax. 41 00:03:32,870 --> 00:03:39,380 The only thing you really need to be aware of is that in a for loop you can not use round rackets so 42 00:03:39,380 --> 00:03:41,120 you cannot use phantasies. 43 00:03:41,180 --> 00:03:43,020 They have to be like this. 44 00:03:43,040 --> 00:03:47,610 If I put practice is I'm guessing it's going to give me some sort of error. 45 00:03:47,630 --> 00:03:48,190 Yes. 46 00:03:48,290 --> 00:03:50,770 So you cannot use around brackets. 47 00:03:50,780 --> 00:03:55,700 It has to be for the name of whatever you are doing so on and so forth. 48 00:03:55,880 --> 00:04:03,130 You could also do four in which is again very simple for any type get in. 49 00:04:03,290 --> 00:04:04,070 Hello. 50 00:04:05,960 --> 00:04:15,370 All trains any not like that of course trained any tactician that's about that. 51 00:04:15,540 --> 00:04:22,400 So this is essentially using for each object in my aere or whatever that we have been doing in the past. 52 00:04:22,560 --> 00:04:28,430 So use exactly identically except that now sprinting H E L L O. 53 00:04:28,560 --> 00:04:33,070 And in here again you don't need to have the round brackets. 54 00:04:33,070 --> 00:04:39,100 Now let's have a look at the do while and repeat vide which is essentially the do while. 55 00:04:39,120 --> 00:04:47,760 So if I have a value about my counter which is five I can say repeat. 56 00:04:48,270 --> 00:04:50,770 And this is the action I want to repeat. 57 00:04:50,820 --> 00:04:52,850 Let's say brains. 58 00:04:53,070 --> 00:04:54,370 What do I want to paint. 59 00:04:54,420 --> 00:04:57,010 Hello All right. 60 00:04:57,100 --> 00:05:00,170 Why what's the condition I want to use. 61 00:05:00,180 --> 00:05:02,180 Why is my counter. 62 00:05:02,400 --> 00:05:06,710 My counter is still larger than zero. 63 00:05:07,150 --> 00:05:14,470 And of course you have to change the condition so I can save my counter minus equal one. 64 00:05:14,580 --> 00:05:16,890 So it keeps subtracting from itself. 65 00:05:16,920 --> 00:05:21,070 If I run this is going to say hello hello hello hello hello. 66 00:05:21,090 --> 00:05:29,460 Underneath the stops and of course we have done this was obviously very simple to do while in Objective 67 00:05:29,460 --> 00:05:31,160 C or other languages. 68 00:05:31,260 --> 00:05:33,120 And of course we have the while loop. 69 00:05:33,240 --> 00:05:39,730 So I'm going to say counter to and that's going to be zero. 70 00:05:40,080 --> 00:05:42,040 And then I'm going to say why. 71 00:05:42,390 --> 00:05:42,910 What is it. 72 00:05:42,910 --> 00:05:48,280 Why it is voile counter to is still a smaller than 10. 73 00:05:48,720 --> 00:05:50,750 I wanna do this. 74 00:05:50,820 --> 00:05:52,190 What do I want to do. 75 00:05:52,230 --> 00:05:54,470 I want a prince. 76 00:05:54,600 --> 00:05:58,190 It's less or anything like that. 77 00:05:58,370 --> 00:06:04,910 And I want to say that the counter too keeps adding to itself plus equal 1. 78 00:06:05,250 --> 00:06:07,540 So let's run that. 79 00:06:07,550 --> 00:06:13,370 No it says it's less it's less is less it does it for 10 times from 0 to 9. 80 00:06:13,380 --> 00:06:16,260 As it says in here 10 times and that's about that. 81 00:06:16,500 --> 00:06:24,840 So once again if statements you don't have to have round brackets you must have curly brackets for the 82 00:06:24,840 --> 00:06:27,900 body of the if condition switches. 83 00:06:27,900 --> 00:06:34,990 You don't need to have Brekke unless you don't care about that case such as the default case for loops. 84 00:06:35,040 --> 00:06:41,670 You use them for whatever variable name you want in the range that you want. 85 00:06:41,940 --> 00:06:49,440 For the for in loops you use for anything that you want in whatever that you're trying to do. 86 00:06:49,830 --> 00:06:56,910 And then we have the loops which are exactly like what we had in Objective-C and we have repeat wind 87 00:06:57,150 --> 00:07:00,330 which is likely to do while in Objective-C. 88 00:07:00,630 --> 00:07:06,180 So there is one more thing I should mention even though it is not such a common thing but just so that 89 00:07:06,180 --> 00:07:14,520 you get a sense of it is what if you want it to have a for loop that goes through a set of numbers but 90 00:07:14,610 --> 00:07:16,560 it doesn't go one by one. 91 00:07:16,560 --> 00:07:19,130 What if your steps were to be different. 92 00:07:19,140 --> 00:07:27,960 What if in Objective C I wanted to say into Ivon 2 0 to 10 and I class equal of 5 or 4. 93 00:07:27,960 --> 00:07:30,550 I wanted to jump every four steps. 94 00:07:30,720 --> 00:07:33,440 So in interest we do that like this. 95 00:07:33,450 --> 00:07:42,420 Like I said it's not a very common thing but for all I gain astride on my stride has from two unbiased 96 00:07:42,840 --> 00:07:48,310 zero to 100 every 15 and then you do whatever you want. 97 00:07:48,310 --> 00:07:52,360 Doing so from a stride from 2 by. 98 00:07:52,560 --> 00:07:55,040 That's where you do things that you wanted. 99 00:07:55,260 --> 00:07:58,520 So let's keep it up to here and we'll move on to our next lesson.