Prefix.pch error in Xcode - objective-c

I get the following error in Xcode, when building project. Can someone help me fix it?
#ifdef __OBJC__
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#endif
with this error:
Prefix.pch:6:38: error: Foundation/Foundation.h: No such file or directory
Prefix.pch:7:28: error: UIKit/UIKit.h: No such file or directory

Sounds like you're not linking against the frameworks correctly, or more likely aren't copying the headers somehow. Likely you accidentally changed the include path of the project.

You have to include the Frameworks:
UIKit.framework
Foundation.framework

Related

Objective-C Class Not Found In Swift Bridging Header

I am updating our Cordova framework and I am stuck on getting a particular Objective-C plugin class to work.
In my old (un-updated) project everything works just fine. I have a BridgingHeader.h file, its properly referenced in the build settings. However in my new updated project it can no longer find only one Objective-C class (PushPlugin.m).
What's strange is its finding all other Objective-C classes just fine, its just the PushPlugin.m it can't find.
Here is my BridgingHeader:
#import <Cordova/CDV.h>
#import <objc/runtime.h>
#import <Parse/PFObject.h>
#import <Parse/PFSubclassing.h>
#import <Parse/Parse.h>
#import <objc/message.h>
#import "GPUImage.h"
#import "PushPlugin.h" // This one is not found
#import "CDVParsePlugin.h"
And when I try to use PushPlugin I get not found error:
//AppDelegate.swift
let pushHander:PushPlugin = getCommandInstance("PushPlugin") as! PushPlugin
// ERROR: PushPlugin not found
To be extra certain, the PushPlugin file is referenced in the Compile Sources. And my BridgingHeader is properly referenced in the build settings.
Do you have any idea why one specific Objective-C class is not being found?
Update
So to be clear, there is no error reporting the BridgingHeader file. Its only when I try to use the PushPlugin that I encounter the error (meaning its not importing properly).
As suggested I ran a commandline build I got a build failed with these reasons:
** BUILD FAILED **
The following build commands failed: CompileSwift normal arm64
/Users/user/Desktop/mobile-cordova-upgrade/app/platforms/ios/App/Classes/AppDelegate.swift
CompileSwiftSources normal arm64 com.apple.xcode.tools.swift.compiler
(2 failures)

Swift compiler error when adding ObjC .h to bridging header

I am getting a weird error on my application when trying to add an ObjC .h file to the bridging header. In particular, when I try to add the header for STXFeedPhotoCell.h, the project fails to compile with the following error (this error is displayed in STXFeedPhotoCell.h. Here is my bridging header:
#import "NetworkHelper.h"
#import "ArtistModel.h"
#import "UIImageView+Masking.h"
#import "CommentModel.h"
#import "LoginViewController.h"
#import "STXFeedPhotoCell.h"
And here is the error thrown:
/pathToProject/Helden der Volksmusik/STXDynamicTableView/Cells/STXFeedPhotoCell.h:12:9: 'NSDate+DateTools.h' file not found
Indeed, STXFeedPhotoCell.h, has an import statement for file NSDate+DateTools.h.
If I remove line #import "STXFeedPhotoCell.h" from the bridging header, then everything compiles fine.
Would appreciate any pointers on why the compiler is getting this error, or if there is a problem in the way these dependencies are being managed for swift (I am using cocoa pods with frameworks enabled).
To import DateTools and use it in Swift, you have to add this to your bridging file:
#import "DateTools/NSDate+DateTools.h"

JSONHTTPClient.m - "use of undeclared identifier UIApplication" build error (line 387)

I just added JSONModel to my projected, according to instructions:
Download the JSONModel repository as a zip file or clone it
Copy the JSONModel sub-folder into your Xcode project
Link your app to SystemConfiguration.framework
tried to build, and... build error!
"use of undeclared identifier UIApplication" build error (line 387)
How to solve it?
I found a solution in here :
To fix it I added this , just below #import "JSONHTTPClient.h" (in JSONHTTPClient.m):
#ifdef __IPHONE_OS_VERSION_MAX_ALLOWED
#import < UIKit/UIKit.h> //<-delete the space, I couldn't write it without
#endif
add #import UIKit; in JSONHTTPClient.h file

Unit Test build failing when importing MagicalRecord

I have a project setup using the UnitTest template provided by Apple. Too I added MagicalRecord to Prefix header. When I am running on the device and Simulator everything is working fine.
Except the Unit Tests, when I am compiling for the unit tests the build failed with the following command: 'CoreData+MagicalRecord.h' file not found . This happens in the prefix header.
prefix.pch
//
// Prefix header for all source files of the '123tv' target in the '123tv' project
//
#import <Availability.h>
#ifndef __IPHONE_3_0
#warning "This project uses features only available in iOS SDK 3.0 and later."
#endif
#ifdef __OBJC__
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import "Environments.h"
#import "CoreData+MagicalRecord.h"
#import "PBLog.h"
#endif
Has anyone an idea?
Make sure that the Header Search Paths is set up correctly for your test target.
I generally use CocoaPods which will automate this stuff for you
Try to run command (1) in terminal, then add import in step (2)
In your project directory
run pod update
You should now be able to add
#import <MagicalRecord/CoreData+MagicalRecord.h>
to any of your target's source files and begin using MagicalRecord!

Why do Xcode templates have #imports that duplicate Prefix.pch?

While learning iPhone programming, every Xcode template I've seen includes an AppName-Prefix.pch file with the following contents:
#ifdef __OBJC__
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#endif
My understanding is that this file's contents are prefixed to each of the source code files before compilation. Yet each of the other files also imports UIKit, which seems superfluous. For example, main.m begins...
#import <UIKit/UIKit.h>
int main(int argc, char *argv[]) {
...
Cocoa applications in Mac OS X do the same thing, importing Cocoa.h in both the prefix file and the header files.
Why have both? I removed the #import directives from all of the source files except the prefix file, and it compiled and ran correctly.
My understanding is that this file's contents are prefixed to each of the source code files before compilation
That's basically correct but you need to understand the subtle points: Every compilation from Xcode eventually boils down to an invocation of gcc or clang. What XCode does is to compile the X.pch file first:
clang -x X.pch -o X.pch.gch
and then when an individual source file (say a.m) is compiled, it issues
clang -include X.pch a.m -o a.o
which loads the pch file, triggering the use of the precompiled header. So, from the point of view of the compiler, it's not really that the content of the pch file is automatically prefixed. Rather, Xcode prefixes the precompiled header to a file when it invokes the compiler.
A future version of XCode might just stop doing it. So, it's better to keep #imports in your .m or .h files, too.
You can also think of it this way: the use of the pch file is just what Xcode does for us behind the scenes to speed up the compilation process. So, we shouldn't write codes in a way it essentially depends on it, like not importing UIKit.h file from our .m/.h files.
(Also, it seems to me that XCode4's syntax coloring gets confused if you don't import the appropriate header files correctly from the .h and .m files.)
Why have both?
Better safe than sorry. Precompiled headers can be disabled, and since #import won't import anything twice, the overhead is negligible.