Summary of problem
I'm building a calendar app in Swift, and I'd like to start with the UI in this repo: https://github.com/erichoracek/MSCollectionViewCalendarLayout
This repo is written in Objective-C.
However, I'm not sure how to build on top of this Github repo using Swift.
Example of the UI I'd like to use in my calendar:
What I've tried
I successfully installed this library with CocoaPods.
I ran $pod install.
I successfully ran import MSCollectionViewCalendarLayout.
I added a new CollectionViewController on my Storyboard, and assigned it to my custom CalendarViewController class
I tried (dumbly) with the code below in class CalendarViewController,but I get this error message:
"Cannot assign value of type 'MSCollectionViewCalendarLayout.Type' to type 'UICollectionViewLayout'"
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView.collectionViewLayout = MSCollectionViewCalendarLayout
}
I understand I probably have to use self.collectionView.register(cellClass:forCellWithReuseIdentifier:)...but how?
There's some documentation titled "Usage" in the Github, but unfortunately I'm still lost as to how to use it:
There's also an Example.xcworkspace included, written in Objective-C. I've gone through most of it. They include header (.h) and implementation (.m) files for each of the elements that they use.
There's a good answer to a tangential problem here: https://stackoverflow.com/a/45540130/3979651, but this doesn't directly solve my problem. I'd like to import this Cocoapods library, instead of writing on top of Objective-C files. But I'm also not entirely sure if this is the right / best way to do it.
Summary of questions
How do I link my CollectionViewController to MSCollectionViewCalendarLayout so that it has the same UI?
How do I use self.collectionView.register(cellClass:forCellWithReuseIdentifier:) in this case?
Do I have to write a new file for each element, like in the Example? (Event cell, Day Column Header, etc.)
Or, would it be easier to just copy and paste the Example element files (.h and .m) into my app? If so, how do I build on top of those files?
What I'd like to accomplish
I would like to import MSCollectionViewLayout like a library, attach it to my own CollectionViewControllers, and build my own functionality on top of this, all using Swift.
Thank you all in advance! Hopefully I can commit the correct answers here to the repo's README.md file.
You can better use one of the below repos which are purely written in Swift and has the same UI as of MSCollectionViewLayout
1) CalendarKit
2) Calendar
Note: I personally used these libraries and these are easy to
integrate with your existing application.
I'm attempting to import my "-Swift.h" file into one of my Objective-C .h files but xcode keeps telling me that the file doesn't exist
#import "Aesculus-Swift.h"
If I command click on the file name it will take me to the generated header file so I know it exists. Why is xcode not able to find it?
This seems like just another issue with Xcode and it's complex tool chain of static analysers and compilers.
Openradar lists radar://21362856 - Swift to Objective-C bridging is unreliable. I am sure there are more but I stopped looking after finding one for this example.
The author imarcelv notes in the description:
I asked a Swift engineer at WWDC in a lab and even he didn't know how to fix this issue.
Steps to Reproduce:
Add a ramdom Swift class to an Objective-C project
Add the #import "ModuleName-Swift.h" file that Xcode generates automatically
Try to use it or just try to compile the project
From time to time it simply doesn't work
It's probably best to file a radar on this issue as it seems that others are already calling it out.
One other thing you could try...
Historically, it was possible for Xcode to completely lose it's syntax highlighting and you could always find out what files the static analyser was giving up on by increasing log level of clang.
I'm not sure if it's still relevant but if I was in your position I'd be trying this command:
defaults write com.apple.dt.Xcode IDEIndexingClangInvocationLogLevel 3
This generates logs you can search with using Console.app for just xcode to highlight the messages. You'll want to trash the derived data of your project to force it to re-compile things.
Although not the same issue as what you're seeing, I have had this post on the syntax highlighting issue bookmarked for years for the above defaults write command to try in times like these.
I solved this recently by adding the following entry to my .xcconfig (you could add it in Xcode's Build Settings > User Header Search Paths if you prefer).
USER_HEADER_SEARCH_PATHS = $(BUILT_PRODUCTS_DIR)/MyFramework.framework/Headers
This tells the compiler to search for headers in the build output directory, which is where Xcode puts the generated header (at least in the case of this framework).
In my case this is a directory like ~/Library/Developer/Xcode/DerivedData/MyProject-LongCode/Build/Products/Debug-iphonesimulator/MyFramework.framework/Headers/MyFramework. You might find your generated header in there too.
Xcode's header and dependency management is a hot mess, and it's not surprising that it doesn't work for you.
I had trouble with this stuff & found that your -Swift file is the Product name of your Target ( not just the name of your Target ) . I found the details here helpful: http://ericasadun.com/2014/08/21/swift-calling-swift-functions-from-objective-c/
When you encounter such situation, just find your kinda "ProductName-Swift.h" file by just cmnd+click on it (even if xcode shows warning about it is not found, the #import "Aesculus-Swift.h" string is still clickable) and then in opened code editor window choose context menu and "Show in Finder" item, then explicitly add it to your project.
I have recently been working to add Swift to an existing project, to get to try it out in a real-world fashion.
Upon adding a Swift source file to the project, I have no problems about getting the "Bridging Header", that is, Objective-C to Swift.
But the *-Swift.h header file that is supposed to expose Swift classes either marked #objc or subclasses of ObjC classes, is nowhere to be found :-(
I don't see any specific instructions on how to accomplish the usage of my new subclass, written in Swift, in my main app code (which is still Objective-C).
The app that I am lead developer of has a fairly large codebase (70.000 lines), so transitioning it in one go is out of the question.
Now it works.
Project must have a Product Module Name that does not include spaces.
Defines Module must be set to Yes in Build Settings, under Packaging.
Finally works. Thanks to everyone for the help :-)
I had a similar problem and found that you can only add
#import "ProductModuleName-Swift.h"
to obj-c .m files, not .h files for the umbrella header to be found
I found that I had to fix all build errors before it would generate the file.
The problem for me was that it was a chicken/egg problem, in that I didn't see any build errors until I'd actually commented out the #import statement:
//#import "ProductModuleName-Swift.h"
which revealed a bunch of other errors in my Swift code.
Once I fixed these new errors and got the source building successfully, I uncommented out the #import and bingo! The header was created and importing correctly :)
If you're like me you've probably got the header name wrong. After bashing my head for a while I looked for the file in DerivedData and sure enough it's there. On my setup (using the standard derived data folder, I believe):
cd ~/Library/Developer/Xcode/DerivedData
find * -iname '*Swift.h'
Will find it. If nothing in that folder matches then Xcode is not generating it.
I'm using Xcode Version 6.2 (6C86e)
If your project module name has spaces in it, you must replace the spaces with an underscore.
For instance, if your project name is "My Project", you would use:
#import "My_Project-Swift.h"
* The only important thing is: *
to use the defined "Product Module Name" in the target, followed by -Swift.h
#import <Product Module Name>-Swift.h
// in each ObjectiveC .m file having to use swift classes
// no matter in which swift files these classes sit.
No matter if "Defines Module" param is set to Yes or No or if "Product Module Name" Project is not set.
Reminder: Swift classes must deriving from NSObject or been tagged with #objc attribute in order to be exposed to ObjectiveC / Foundation || Cocoa ...
I wanted to add one more reason you might find an issue with this - I was creating a framework that mixed Swift and Objective-C code. I was not able to import the Swift classes outside the framework - I checked for the -Swift.h file and it was being generated but was empty.
The problem turned out to be very, very simple - I had not declared any of my Swift classes public! As soon as I added the public keyword to the classes, I was able to use them from classes inside and outside the framework.
Also of note, inside the framework (inside .m files only as another answer mentions) I had to import the -Swift.h file as:
#import <FrameworkName/FrameworkName-Swift.h>
I had the same problem. Seems like you have to adjust the settings (Defines Module and Product Module Name) before you add your first Swift file.
If you do it afterwards the "*-Swift.h" file will not be generated for this project even if you add further Swift files or delete the Swift file and create a new one.
Allow me to share my experiences trying to use Swift in an old objc project. I did not have to set Defines module to YES.
In my case I needed to manually make sure there was an objc Bridging Header. Only the generated interface header name was present in my build settings.
This lead to a MyApp-Swift.h file to being generated, but without any traces of my Swift classes.
The Apple documentation says that you will be prompted to create a bridging header when adding your first swift file. Well, I wasn't. I manually added a MyApp-Bridging-header.h file and pointed to it in the "Objective-C Bridging Header" field. That made my MyApp-Swift.h file become populated with my Swift classes.
Docs: Importing Swift into Objective-C
Here is another variation of the moduleName-Swift.h not being generated.
I decided to include IOS Charts in my project but did not want to mingle the sources in the same directory, so I placed the Charts Project folder next to my code's project folder. I dragged the Charts project into my Project's Navigator Bar and included the framework in the my project target's Embedded Binaries list in the General project settings and set the Embedded Content Contains Swift Code switch to yes in my project's Build Settings tab in the Build Options section.
My project's moduleName-Swift.h file would never generate no matter what other switches or settings suggested here. Finally, using Lou Z's method of seeking out the -Swift.h files, I saw that a Charts-Swift.h file was being generated deep in my project's xcode Build directory in Charts.framework/Headers/
The solution to using Daniel Gindi's ios-charts Swift package without including the code in my project's source directory was to add:
#import "Charts/Charts-Swift.h"
To the modules charting my project's data.
The file name is always preceded by your Target name. It is referred as Product name but practically it is the target name.
So if you want it to build for a new target be ready to expect that_target-Swift.h file.
One way to handle this is
Add a preprocessor for each of your target that is the name of your target itself (without spaces). Ex. MY_TARGET=1. Add this in Project settings->Build Settings->Preprocessor Macros for each of your targets.
If you are using a PCH file,
Add these lines in the PCH file
#if MY_TARGET==1
#include "My_Target-Swift.h"
#elif THAT_TARGET==1
#include "That_Target-Swift.h"
#endif
Advantage of using PCH file is that you don't have to include the headers everywhere.
If you are not using a PCH file, just add these same lines in a single header and include that header wherever you need to use the swift classes.
This should work just fine.
If Xcode is actually generating your -Swift.h header (deep inside DerivedData) but it doesn't refer to your Swift classes, make sure you also have a bridging header defined. The way I read the docs implied I only needed that for calling Objective-C from Swift, but it seems to be necessary for calling Swift from Objective-C too.
See my answer: https://stackoverflow.com/a/27972946/337392
EDIT: It is because of public vs. internal access modifiers, as I eventually found explained in the Apple docs:-
By default, the generated header contains interfaces for Swift
declarations marked with the public modifier. It also contains those
marked with the internal modifier if your app target has an
Objective-C bridging header.
Seconding what a lot of people have here, but adding a pertinent screen shot. Swift and Obj-C code can certainly live together. It's not an all or none game.
To access Swift files in your Objective-C, all you need to do is add this call to your Obj-C file (in the .m / implementation file):
#import "{product_module_name}-Swift.h"
(Where {product_module_name} represents the product module name of your project). Rather than try to guess your product module name or figure out corner cases with spaces and special characters, just go to the build settings tab in the project and type in "product module name" - the inspector will reveal yours to you. Mine was something I did not expect it to be. Check out this screen shot if you're confused.
And to get Obj-c code working in Swift, you just need to add a bridging header file and import the relevant Obj-C headers there.
This answer addresses the use-case where you may already have some Objective-C code that calls Swift classes and then you start receiving this error.
How To Fix Issue
The following steps ultimately resolved all of the issues for me. I read above someone mentioning the "chicken and the egg" and it is exactly that concept which led me to this procedure. This explicit process shows that one has to remove any Objective-C code referencing Swift classes until after the header is generated.
Comment out the #import "ProductModuleName-Swift.h" statement in
your Objective-C implementation file
Comment out any references in the Objective-C implementation file to
Swift Classes
Clean & Build
Resolve all errors/warnings
Remove the comment on the #import "ProductModuleName-Swift.h" statement
Clean & build (successfully or fix any remaining errors, verify that you are not referencing any Swift classes in Objective-C at this point. If so temporarily comment these out)
Verify that "ProductModuleName-Swift.h" is generated by Cmd-Clicking
on the class name of the #import "ProductModuleName-Swift.h" statement
Remove the comment on the code referencing Swift classes in the Objective-C implementation file.
Clean & Build as normal (the "ProductModuleName-Swift.h" should be
generated and your Objective-C code referencing Swift Classes can be
used as normal)
Nota Bene: The answers about changing spaces to underscores and the Defines Module to YES as given above still applies when performing this process, as do the rules specified in the Apple Documentation.
Bridging Header Path
In one error, the file ProductModuleName-Bridging-Header.h was not being found during the build process. This fact generated an error
< unknown>:0: error: bridging header
'/Users/Shared/Working/abc/abc-Bridging-Header.h' does not exist
Closer inspection of the error indicated that the file would never exist at the location described because it was actually located at (a wrong path)
'/Users/Shared/Working/abc/abc/abc-Bridging-Header.h'. a quick search of the target/projects build settings to make the correction manually and the abc-Swift.h file was again auto generated.
Ok, here are all the things you really need!
1.Remove all the swift files you have added, and compile the code, without any errors.
----------
----------
2.Go to the "Projects" build settings, and set the product module name.
Project must have a Product Module Name that does not include spaces.
----------
----------
3.Defines Module must be set to Yes in Build Settings, under Packaging, in your project, and not target!
----------
----------
4.Now create a swift file or a view controller, in file-> newFile->
----------
----------
It will ask to create a bridging-header, allow it to make one.
If you have declined it once, you will have to manually add a -Bridging-Header.h
5.Add #objc in the controller, to tell the compiler that there is some swift file, which needs to be exposed to ObjectiveC
----------
----------
6.Build the project and import #import "-Swift.h" in any of the objectiveC controller, and it will work! You can Command-click on it to see the actual file!
----------
----------
Hope this helps!
The most important thing is that This file is invisible!!! At least it is in Xcode6 beta5. There will be no such file named "YourModule-Swift.h" in your workspace. Just make sure you have module name and defines module set to yes, and use it in your Objective-C class.
You have to import a header in Objective-C classes, which is:
#import “ProductModuleName-Swift.h”
It is automatically generated, on the reference it says "Any Swift files in your target will be visible in Objective-C .m files containing this import statement."
An actual file in the project is not created ([ProductModuleName]-Swift.h). Cmd + Click on the import either generates it on-the-fly (and in-memory) so you can see how the linkage is done, or opens a file somewhere in some Xcode cache dir, but it's not in the project dir.
You need to set Defines Module project prop (in target's Build Settings) to Yes and if your module name has spaces or dashes - use _ in all imports of the [ProductModuleName]-Swift.h file.
You can import it in all .h and .m files where you use swift types or you can import it in the .pch.
So if my Module (project) is named "Test Project", I would import it like this, in the .pch file of my project (just there):
#import "Test_Project-Swift.h"
Just a heads up for anyone who used "." in there project name. Xcode will replace the "." with an underscore "_" for the Swift version of the bridging header file. Oddly enough the Bridging-Header.h that is generated does not replace the periods with underscores.
For example a project with the name My.Project would have the following Bridging Header file names.
Bridging-Header.h (Autogenerated)
My.Project-Bridging-Header.h
Swift.h
My_Project.h
I hope this helps anyone who used a period and was stuck like I was. This file can be found at the following location.
Macintosh HD/Users/user/Library/Developer/Xcode/DerivedData/My.Project-fntdulwpbhbbzdbyrkhanemcrfil/Build/Intermediates/My.Project.build/Debug-iphonesimulator/My.Project.build/DerivedSources
Take care,
Jon
Project must have a Module Name not including spaces.
Defines Module must be set to Yes in Build Settings, under Packaging.
commented out the #import statement:
If still you are having error in importing "ProductModuleName-Swift.h" then
//#import "ProductModuleName-Swift.h"
which revealed a bunch of other errors in my Swift code.
Once I fixed these new errors and got the source building successfully, I uncommented out the #import and bingo! The header was created and importing correctly :)
I found a trick that always works on me.
Create your #import "ProductModuleName-Swift.h" in your appDelegate.h file and in your ProductName-Prefix.pch file. If you don't have it in xcode 6 you can create it with this way Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
Command+shift+k to clean your code, if you receive an error about your "ProductModuleName-Swift.h" delete it from appDelegate.h file.
Clean your code again. Now everything will work like a charm
If you receive again error about the "ProductModuleName-Swift.h", now create again in appDelegate.h file and clean your code again.
Do this work (delete and create the "ProductModuleName-Swift.h" from appDelegate.h file and clean your code) everytime you receive this error to silent it.
I Found this solution
Create SwiftBridge.h
put #import “ProductModuleName-Swift.h”
Make this .h file public (important) Select the file -> In Show the file Inspector (right bar) -> Make it public
Now you can
#import "SwiftBridge.h"
instead of ProductModuleName-Swift.h
This's a workaround solution, for the next version of Xcode I think this problem will be solved.
Good luck
If you were able to build a project before, with no issues related to “ProductModuleName-Swift.h” not found error, and now you are getting that nasty errors again, the reason might sit in your recent changes.
For me this was by (accidental) incorrect .swift file encoding. Reverting changes and bringing the back manually, does the job.
I was having a hard time determining my module name/objective-c's import of swift's headers. I did read a lot of articles here too.
But the definitive answer for your project name with all its included special characters (be it '.' or a numeric or a space) - you can find the text that will work for you in the "Product Module Name" under the target's Build Settings.
For example my target name started with a numeric - "1mg" and the field mentioned above showed "_mg" as my module name.
so I used #import "_mg-Swift.h" and it worked.
This may be an obvious point (maybe too obvious), but you must have at least one swift file in the project for the header to generate. If you are writing boilerplate or config code with the intention of writing swift later the import won't work.
In my case I had to set the deployment target to at least “OS X 10.9” and the -Swift.h header was automatically generated. Keep in mind that you can get a lot of deprecation warnings when you change the deployment target version, especially when you have an older and very large Objective C code base. In our case we also had a lot of work to do in XIB files & view classes.
I had to delete WatchOS2 swift code from my Objective C project. And only after that XCode offered to generate -Swift.h
I had similar problem but my project was compiling before and suddenly got error after few files code change. It took me while to figure out why I am getting 'File not found' error for myproject-swift.h file. The code changes I had done had some errors. Xcode did not point put those error instead all time showing the 'File not found error'. Then got copy of previous version code and I compared with new code and merged file one by one. After each file merge complied the project to find the error. So bottom line is if you have error in your code Xcode may just display 'file not found error' for myproject-swift.h file. Most likely you have compilation error in your project. Clean those error and it will work.
If you're using something like Cocoapods (and working out of the workspace rather than the project) try opening the project and building it before opening the workspace and building. YMMV.
Sometimes you just need to unset and then set again the target membership on the obj-c .m file.
I've added Box2D to a Cocos2D project I'm working on.
I've followed several guides as to how to do this (all of which seem to differ!).
However, none seem to work.
I'm getting these types of errors:
error: Box2D/Collision/b2BroadPhase.h: No such file or directory
I assumed I'd got the Header Search Paths wrong but have tried all sorts of variants with no luck.
Any suggestions?
The easiest way to use Box2d with your project is to follow these lines:
Copy the Box2d files into a subfolder of your project.
Import these files into your project via Xcode.
After in the "Project navigator", select your target and open the “Build Settings” tab.
Set the "Always Search User Paths" to YES.
Then search for the "User Header Search Path" and add this "${PROJECT_DIR}" (think to check the “recursive path“).
That's all!
You just have to be careful when you want to use Box2d. Think to change the extension of your files from .m to .mm to warn the compiler that the class must be compile as Objective-C++ instead of Objective-C.
I have found a good tutorial here (with Xcode 3.2, but the idea is here). I hope it'll help you.
Alternatively ... After a lot of trouble trying to include box2d in my project, I instead used box2d as a static library - takes a minute to setup, but it's much easier to maintain / add to multiple projects. Step by step guide here:
http://red-glasses.com/index.php/tutorials/box2d-for-ios-made-easy-make-it-a-static-library/