xCode 6 如何修复“使用未声明的标识符"用于自动属性合成? [英] xCode 6 how to fix "Use of undeclared identifier" for automatic property synthesis?

问题描述

我正在使用 xCode6 Beta 3，并且遇到了一个问题，以前编译良好的代码(xCode 5.1.1 或 xCode6 beta 2)突然开始给我使用未声明的标识符" 访问自动合成的实例变量时出错:

I'm using xCode6 Beta 3, and am running into an issue where a code which previously compiled fine (xCode 5.1.1 or xCode6 beta 2) suddenly started to give me "Use of undeclared identifier" errors when accessing an automatically synthesized instance variable:

- (void)setFinished:(BOOL)finished {
    [self willChangeValueForKey:@"isFinished"];
    _finished = finished;
    [self didChangeValueForKey:@"isFinished"];
}

//ERROR:
 Use of undeclared identifier '_finished'; did you mean 'finished'?

添加@synthesize finished = _finished; 会使错误消失，但是有没有办法强制 xCode6 Beta 3 使用下划线表示法使用自动属性合成?

Adding @synthesize finished = _finished; makes the error go away, but is there a way to force xCode6 Beta 3 to use automatic property synthesis using underscore notation?

推荐答案

一开始我还以为是 beta 版本的 bug，但是今天看到 XCode 6 GM Seed 也出现了这种类型的错误，虽然我是尚未发现在哪些特定情况下.

At first I thought it was a beta version bug, but today I saw that this type of errors occur on the XCode 6 GM Seed also, though I'm yet to discover in which particular cases.

无论如何，修复方法是在@implementation 块中添加一个合成语句，显式声明 ivar 的名称以及属性:

Anyway, the fix is to add a synthesize statement in the @implementation block, explicitly declaring the name of the ivar as well as the property:

@synthesize property = _property

这篇关于xCode 6 如何修复“使用未声明的标识符"用于自动属性合成?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IT屋！