在swift中使用Objective-C块

I have a third party Objective-C library in my swift project, in one of the .h files, it has a typedef:

我在swift项目中有一个第三方Objective-C库,在.h文件中,它有一个typedef:

typedef void (^YDBlutoothToolContectedList) (NSArray *);

typedef void(^ YDBlutoothToolContectedList)(NSArray *);

and inside the class, it has a property:

在课堂内,它有一个属性:

@property (nonatomic, copy) YDBlutoothToolContectedList blutoothToolContectedList;

@property(非原子,复制)YDBlutoothToolContectedList blutoothToolContectedList;

(please ignore its spelling)

(请忽略其拼写)

When I try to use this property in my swift class, I use

当我尝试在我的swift类中使用这个属性时,我会使用

bt.blutoothToolContectedList = {(_ tempArray: [Any]) -> Void in
    self.devices = tempArray
    self.tableView.reloadData()
}

and I got the error says:

我得到错误说:

Cannot assign value of type '([Any]) -> Void' to type 'YDBlutoothToolContectedList!'

无法指定类型'([Any]) - > Void'的值来输入'YDBlutoothToolContectedList!'

I know the above Objective-C code in swift would be:

我知道swift中的上述Objective-C代码是:

typealias YDBlutoothToolContectedList = () -> Void

typealias YDBlutoothToolContectedList =() - > Void

but I can't re-write that Objective-C file and swift can't cast the closure type, is there a possible way to solve this problem?

但是我不能重写那个Objective-C文件和swift无法转换关闭类型,有没有可能解决这个问题的方法呢?

1 个解决方案

#1

typedef void (^YDBlutoothToolContectedList) (NSArray *);

is mapped to Swift as

映射到Swift as

public typealias YDBlutoothToolContectedList = ([Any]?) -> Swift.Void

because the closure parameter can be nil. (You can verify that by selecting the .h-file and then choosing Navigate->Jump to Generated Interface in the Xcode menu.)

因为闭包参数可以是零。 (您可以通过选择.h文件,然后在Xcode菜单中选择Navigate-> Jump to Generated Interface来验证。)

Therefore the correct assignment would be

因此,正确的任务将是

bt.blutoothToolContectedList = {(_ tempArray: [Any]?) -> Void in
    // ...
}

or simply let the compiler infer the parameter type:

或者只是让编译器推断出参数类型:

bt.blutoothToolContectedList = { tmpArray in
    // ...
}

If you could add a nullability annotation to the Objective-C definition:

如果可以为Objective-C定义添加可空性注释:

typedef void (^YDBlutoothToolContectedList) (NSArray  * _Nonnull );

then it would be mapped to Swift as

那么它将被映射到Swift as

public typealias YDBlutoothToolContectedList = ([Any]) -> Swift.Void

#1

typedef void (^YDBlutoothToolContectedList) (NSArray *);