Xcode 7 Null 传递给需要非空参数的被调用方
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Xcode 7 Null passed to a callee that requires a non-null argument
提问by Uyghur Ilan
i updated xcode 7 and gives this error
我更新了 xcode 7 并给出了这个错误
Null passed to a callee that requires a non-null argument
Null 传递给需要非空参数的被调用方
_recorder = [[AVAudioRecorder alloc]initWithURL:[NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@.%@", [NSHomeDirectory() stringByAppendingString:@"/Documents"], name, extension]] settings:nil error:nil];
回答by ruiaureliano
If what bothers you is the warnings, you can supress that using this -Wnonnull
如果让你烦恼的是警告，你可以使用这个来抑制它 -Wnonnull
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wnonnull"
_recorder = [[AVAudioRecorder alloc]initWithURL:[NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@.%@", [NSHomeDirectory() stringByAppendingString:@"/Documents"], name, extension]] settings:nil error:nil];
#pragma clang diagnostic pop
回答by Rainer Schwarze
An easy way to check is to use Show Completions- go to a method name and press Ctrl-Spaceor in the menu Editor> Show Completions. A window will pop up. Look for entries with (nonnull)- these must not be nil. For example:
一种简单的检查方法是使用Show Completions- 转到方法名称并按Ctrl-Space菜单中的 或Editor> Show Completions。会弹出一个窗口。查找带有(nonnull)- 这些不能是 的条目nil。例如：
I pressed Ctrl-Spacewith the cursor in [NSString stringWithFormat:...]. As you can see a lot of arguments are marked (nonnull).
我Ctrl-Space用光标按下[NSString stringWithFormat:...]. 正如您所看到的，很多参数都被标记为(nonnull)。
When you explicitly pass nilin your method call, you already found the problem. If you pass a variable, check whether that is nilat that time.
当您显式传入nil您的方法调用时，您已经发现了问题。如果你传递了一个变量，检查它是否nil在那个时候。
回答by Pooja krishna p.b
I got this issue while using a custom completion handler . The warning occured while passing nil value for the handler. So I have added __nullablewith completion.
我在使用自定义完成处理程序时遇到了这个问题。为处理程序传递 nil 值时发生警告。所以我添加__nullable了完成。
typedef void (^ __nullable completionHandler)(void);
