IB在IBAction，IBOutlet等中意味着什么？

问题描述

我是iPhone开发的新手。我经常在阅读Objective-C和Swift代码时遇到 IBAction ， IBOutlet 等等。 IB 代表什么？

I am very new to iPhone development. I often encounter IBAction, IBOutlet and so on when reading Objective-C and Swift code. What does IB stand for?

推荐答案

Interface Builder。

"Interface Builder".

在Xcode 4之前，接口文件（XIB和NIB）是在一个名为Interface Builder的独立程序中编辑的，因此是前缀。

Before Xcode 4, the interface files (XIBs and NIBs) were edited in a separate program called Interface Builder, hence the prefix.

IBAction 定义为 void ， IBOutlet

IBAction is defined to void, and IBOutlet to nothing. They are just clues to Interface Builder when parsing files to make them available for connections.

只需添加引用，在AppKit / NSNibDeclarations.h中你会发现：

Just to add the reference, inside AppKit/NSNibDeclarations.h you'll find these:

#ifndef IBOutlet
#define IBOutlet
#endif

#ifndef IBAction
#define IBAction void
#endif

所以，实际上，代码就像这个：

So, actually, code like this:

@interface ...
{
    IBOutlet NSTextField *label;
}
- (IBAction)buttonPressed:(id)sender;
@end

将转换为：

@interface ...
{
     NSTextField *label;
}
- (void)buttonPressed:(id)sender;
@end

通过预处理器，甚至在编译器看到它之前。这些关键字就像Interface Builder一样。

By the preprocessor, even before the compiler sees it. Those keywords were acting just as clues to Interface Builder.

这篇关于IB在IBAction，IBOutlet等中意味着什么？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！