I am importing my Objective C classes in a bridging header file into Swift:
Bridging Header
#import "MyCustomClass.h"
In my swift class, I am trying to use this code:
var x = MyCustomClass()
x.myFunMethod()
However, before I run/build I get "Use of unresolved identifier" errors at the above two lines. Furthermore, I cannot use autocomplete to type out x.myFunMethod(). Once I run/build, the errors go away and the app runs as normal.
Related
when I want use swift file in objective c project and I declare an object from swift class, I get "Use of undeclared identifier" error.
the way that I pass:
coping swift file in project and type #objc before declare swift class
create header file in project manually
set "Defines module" in target to Yes
set objective-C bridging header in target to $(SRCROOT)/$(PRODUCT_MODULE_NAME)-Bridging-Header.h
declare #import "productModuleName-Bridging-Header.h" in objective-c file
use name_of_swift_class *s = [[name_of_swift_class alloc] init];
when I want use swift file in step 6 I get "Use of undeclared identifier" error. why?!!! do I have the mistake?
when I test this steps in new project I don't get error but in project that I want it return error.
thank you for your help
The problem is at Step 5 You should not be importing "productModuleName-Bridging-Header.h" instead you should be importing "productModuleName-Swift.h"
P.S- After making this change clean your project, clear your derived data and build it. It will work. Hope it helps :)
This is a partial duplicate of Import a file in bridging-header which imports Swift header but I encounter the same issue as Rich
But what about enums declared in Swift? :(
I am porting an Obj-C iPad app to the iPhone. However I am a Swift developer who would really rather not rewrite existing functionality; replacing the UI instead.
I created a new target for the iPhone version. In my bridging header I import an obj-c class that uses #import "ProjectName-Swift.h". Since this file is autogenerated it doesn't exist when I build this new target. The linked answer is to add a #class but the legacy code makes use of an enum which is now giving the error "Expected a type".
// File that I am currently importing
-(void)setSmileyType:(SmileyFace)type andDelegate:(id<NumberRatingDelegate>)delegate;
// This line now throws an error "Expected a type"
//File that was previously auto imported
#objc public enum SmileyFace: Int {
#objc enum in Swift is exposed as a C-enum in ProjectName-Swift.h .
(Using a macro SWIFT_ENUM.)
You can put something like this into your Objective-C header files which are using the Swift enum:
typedef enum SmileyFace: NSInteger SmileyFace;
(Same as the first part of the generated code with the macro SWIFT_ENUM.)
I have done this before, normally without trouble, setting the bridging header, etc.
This time, I tried to import a Obj-C framwork (github.com/jensmeder/FSKModem/) into my swift project. When typing code I can "see" all the Obj-C methods.
But when I compile the code, I get errors like "Use of undeclared identifier 'delete'" or "Use of undeclared identifier 'new'". Example of code in a .m file that is giving the error:
_audioFormat = new AudioStreamBasicDescription();
I'm familiar with Swift and don't know about Obj-C but I guess "delete" or "new" should exist, right? Do they belong to some framework that I should add?
I can compile the original code in Obj-C without trouble, but I need to incorporate it in my project that is written in Swift.
Many thanks for any help
Some more information...
The following functions are inside the .m file. Do you know why the "new" and "delete" keywords are unrecognized? This works fine when compiled as a normal "Obj-C" project. The error appears in Swift project only (after bridging headers of course):
-(void)dealloc
{
[self disconnect:NULL];
if (_audioFormat)
{
delete _audioFormat;
}
}
-(void) setupAudioFormat
{
_audioFormat = new AudioStreamBasicDescription();
//...
}
Should I add some #include that I might be missing, besides Foundation?
new and delete are C++ keywords; you can use them in C++ files (usually .cpp or .cc) and in Objective-C++ files (always .mm). You cannot use them in Swift (.swift) or in Objective-C (.m) files.
It is perfectly valid to use an Objective-C class from an Objective-C++ file from Swift; you can use Objective-C to wrap C++ classes for Swift usage. However it is not valid to use C++ from plain Objective-C.
Quite probably you just need to rename your Objective-C file to .mm.
new and delete are keywords from C++ not from Swift or Objective-C.
Swift
let audioFormat = AudioStreamBasicDescription()
Objective-C
AudioStreamBasicDescription* audioFormat = [[AudioStreamBasicDescription alloc] init];
In Swift, you simply need to call the object initializer when creating an object.
_audioFormat = AudioStreamBasicDescription()
The new keyword is an Objective-C combo of alloc and init.
I'm working on an objective-c project. I added a swift framework, which gave me errors.
When I touch "command" can find the file. When I use #import also can add "ChartLineView.swift".
But when I implement it as,
ChartLineView *cl = ....
I get an error, " Use of undeclared identifier LineChartView"
What could be wrong?
I guess your are having issue in importing swift library(added via cocoapods) in your Objective C project. Just go in your .m file and import the swift library like this.
#import LineChartView; // i suppose LineChartView is the swift library name.
I have ported an objective-c package into a swift package and included it within the bridging header. Everything works fine, except there is a function I have to implement from a delegate I can't get working:
- (void) mdwamp:(MDWamp*)wamp sessionEstablished:(NSDictionary*)info;
Does anyone know how I can implement this in SWIFT?
In the bridging header make sure you imported the objective-c header.
After doing that, you can use the following.
var instance: ClassName = ClassName()
instance.mdwamp(wamp, sessionEstablished: info)