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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第六章
如果你的程式碼正執行在背景佇列上並且想要更新 GUI，你必須執行主要佇列上的 GUI
更新程式碼，要這樣做的一種方法就是為主要佇列添加 block ︰
[newQueue addOperationWithBlock:^{
// 在背景做某事
// 在主要佇列上排程 block
[mainQueue addOperationWithBlock:^{
// GUI 工作可在這裡安全地被執行。
}];
}];
任何與 GUI 有關的工作都只能由主要佇列來完成，如果你從任何其他佇
列進行，應用程式就會當掉。
組織起來
我們現在要撰寫從多個網站非同步下載 favicon（網站圖示，即 website icon）的應用程
式，它也會在應用程式退出時與伺服器聯繫。請遵循以下步驟，建立這支新的 App ︰
1. 建立新的單視圖應用程式。
2. 為視圖控制器添加表格視圖。
3. 把表格視圖的原型儲存格樣式（prototype cell style）改變成
Basic
。
4. 選取原型儲存格，將它的識別符改成
IconCell
。
5. 把該表格的 Selection 樣式改成
No Selection
。
6. 讓視圖控制器成為表格視圖的資料來源（data source）與代理（delegate）。
7. 在輔助編輯器（Assistant）裡打開
ViewController.h
，讓
ViewController
遵循
UITableViewDataSource
和
UITableViewDelegate
協定。
8. ...
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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.