June 2013
Intermediate to advanced
360 pages
6h 50m
Chinese
Content preview from COCOA學習手冊--使用OBJECTIVE-C第三版
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
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第九章
雖然 iCloud 提供方法讓你把檔案和檔案夾儲存在雲端，但你也必須瞭解
如何將文件呈送給使用者。本章僅說明儲存資料的機制；要更仔細地瞭解
如何在 OS X 和 iOS 上撰寫奠基於文件（document-based）的應用程
式，請參閱第 12 章。
鍵值編程
Cocoa 提供一種稱作鍵值編程（key-value coding）的功能，讓你透過名稱來設定及擷取
物件的值，而非透過明確地呼叫合適的方法。只要你的類別根據一些簡單的規則來命名
你的特性與方法，你就能夠利用字串來參照類別裡的資料，而不是透過方法呼叫。這項
功能被 Cocoa 的其他幾個部分充分運用，其中最值得注意的就是 Core Data。
讓我們假設一種狀況，你有一支應用程式從某處（如網路）擷取產品相關資訊，這支應
用程式以下面的類別描述每一項產品︰
@interface Product : NSObject
@property (strong) NSString* productName;
@property (assign) float price;
@property (strong) NSString* stockCode;
@property (assign) int numberInStock;
@end
應用程式接受
NSDictionary
，接著必須將它轉變成
Product
類別的實例，處理方法之一
如下︰
- (Product*) productWithDictionary:(NSDictionary*)dictionary ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.