From 6ea472b81c8e21835007a928794bbb638be8564c Mon Sep 17 00:00:00 2001 From: yanqizhao Date: Tue, 29 Sep 2020 14:46:13 +0800 Subject: [PATCH] Completed translation of 2051 - 2100 in lecture 2 --- ...ture 2. MVVM and the Swift Type System.srt | 55 +++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/subtitles/zh-Hans/Lecture 2. MVVM and the Swift Type System.srt b/subtitles/zh-Hans/Lecture 2. MVVM and the Swift Type System.srt index 8264f22..73c26ae 100644 --- a/subtitles/zh-Hans/Lecture 2. MVVM and the Swift Type System.srt +++ b/subtitles/zh-Hans/Lecture 2. MVVM and the Swift Type System.srt @@ -8560,230 +8560,285 @@ Array.Card> 2051 01:33:11,911 --> 01:33:14,410 There's no way of identifying them. +没有办法识别它们 2052 01:33:14,410 --> 01:33:18,810 So, Swift has a formalism, a formal mechanism +所以 Swift 有一套正式的机制 2053 01:33:18,810 --> 01:33:22,670 for identifying something, making something identifiable +能识别变量 2054 01:33:22,670 --> 01:33:25,040 and it does it with something I like to call +我喜欢称之为 2055 01:33:25,040 --> 01:33:27,500 constrains and gains. +“限制与收获” 2056 01:33:27,500 --> 01:33:31,160 So that's when you require a struct to do a certain thing, +这就是当你让结构体做某件事时 2057 01:33:31,160 --> 01:33:34,430 you constrain it to do a certain thing +你限制它做某件事 2058 01:33:34,430 --> 01:33:38,120 but if it does, then it gains certain capabilities. +与此同时，它获得了某种能力 2059 01:33:38,120 --> 01:33:40,560 Now, we're gonna talk all about +下周我们会讨论 2060 01:33:40,560 --> 01:33:44,163 how constrains and gains works next week. +“限制与收获”是如何运行的 2061 01:33:45,250 --> 01:33:47,322 And we've already used constrains and gains, +事实上，我们已经在 :View 这里 2062 01:33:47,322 --> 01:33:51,490 actually, here, colon View was constrains and gains. +使用了“限制与收获” 2063 01:33:51,490 --> 01:33:54,857 We constrained ourselves to have to do this body, okay? +我们限制结构体 ContentView +必须实现 body 中的内容 2064 01:33:54,857 --> 01:33:59,210 But we gained all the stuff that View does, okay? +但我们获得了 View 所具备的能力 2065 01:33:59,210 --> 01:34:01,703 So, that's constraints and gains in the struct. +这就是“限制与收获” +在结构体中的示例 2066 01:34:02,592 --> 01:34:04,950 We're gonna do the same thing with this constrains and gains +接下来我们要在 Card 这个结构体中 2067 01:34:04,950 --> 01:34:06,140 with this struct. +使用“限制与收获” 2068 01:34:06,140 --> 01:34:09,719 We're gonna say constrains and gains Identifiable. +在这里输入 :Identifiable 2069 01:34:09,719 --> 01:34:14,719 Identifiable like View is what's called a protocol +Identifiable 就像 View 一样 +是一个 Protocol（协议） 2070 01:34:15,070 --> 01:34:18,900 and that's the heart of this constrains and gains business. +它是“限制与收获”这个机制的核心 2071 01:34:18,900 --> 01:34:22,640 And again, we'll talk about protocols a lot next week. +我们也会在下周展开来讲协议相关的内容 2072 01:34:22,640 --> 01:34:24,410 Unfortunately, you don't gain much with it +遗憾地是，除了获得可识别的能力 2073 01:34:24,410 --> 01:34:27,080 except where you gain the ability to be identified +你并不能通过 Identifiable 得到更多 2074 01:34:27,080 --> 01:34:29,090 but mostly, you are constrained +但是你主要是被限制了 2075 01:34:29,090 --> 01:34:31,010 and the constraint of Identifiable +Identifiable 的限制是 2076 01:34:31,010 --> 01:34:34,540 is that you have to have a var called id +你需要声明一个变量 id 2077 01:34:34,540 --> 01:34:36,890 Now, luckily, it can be any type you want. +幸运地是，它可以是任何你想要的类型 2078 01:34:36,890 --> 01:34:38,570 I'm gonna make my id be an Int +我要把 id 声明为 Int 类型 2079 01:34:38,570 --> 01:34:41,160 but it could be a String or anything you need to do +但是它也可以是 String +或者任何你需要的类型 2080 01:34:41,160 --> 01:34:43,390 to make this thing identifiable. +让它成为可识别的即可 2081 01:34:43,390 --> 01:34:45,980 Of course, as soon as I add another var here, +当我添加 id 这个变量之后 2082 01:34:45,980 --> 01:34:49,000 now, my Card isFaceUp blah, blah, blah +Card 的构造器 2083 01:34:49,000 --> 01:34:51,610 is not doing all the vars. +就报错了 2084 01:34:51,610 --> 01:34:55,420 So for both of these, I need to add an ID. +所以我需要在这两行添加 id 的值 2085 01:34:55,420 --> 01:34:59,500 And what I'm gonna use for my ID is my pairIndex times two +这里输入 pairIndex*2 2086 01:34:59,500 --> 01:35:01,760 and for this guy's ID because I want this Card +这里，为了让卡片 2087 01:35:01,760 --> 01:35:05,270 to be obviously, to have its own identifier, +有自己的标识符 2088 01:35:05,270 --> 01:35:09,930 I'm gonna do pairIndex times two plus one, okay? +输入 pairIndex*2+1 2089 01:35:09,930 --> 01:35:14,760 So now these things have unique identifiers. +现在，它们都有唯一的标识符了 2090 01:35:14,760 --> 01:35:17,440 Now this is fully identifiable, that's all we need to do, +它们完全可识别了 2091 01:35:17,440 --> 01:35:19,340 we just have to make sure that these Cards +我们只需要确保这些卡片 2092 01:35:19,340 --> 01:35:21,060 are uniquely identifiable, +是独一无二的 2093 01:35:21,060 --> 01:35:22,290 again, so that they move around, +那么，当它们移动时 2094 01:35:22,290 --> 01:35:23,803 we can animate them or whatever. +我们就能展示动画或者进行其他的操作 2095 01:35:23,803 --> 01:35:26,290 By the way, it's a little annoying here +这里稍稍有点烦人 2096 01:35:26,290 --> 01:35:29,360 that I have to say this every time for a new Card. +每次声明一个新的 Card +都要输入这么多 2097 01:35:29,360 --> 01:35:31,660 I could just put that down here, by the way. +我可以在下面输入默认值 2098 01:35:31,660 --> 01:35:35,930 You're absolutely allowed to have some of your vars +你完全可以 2099 01:35:35,930 --> 01:35:37,760 be initialized that way +这样初始化变量 2100 01:35:37,760 --> 01:35:41,160 and then we don't need to have them here, okay? +然后就不用在声明的时候输入这么多了 2101 01:35:41,160 --> 01:35:43,423