On Xcode 11 my .xcassets, that don't cause any issue on Xcode 10, cause the compilation to fail with the following message:
error: Multiple commands produce '/Users/user/Library/Developer/Xcode/DerivedData/project-enjiypsgxtcdbnaripixgtnjlagx/Build/Products/Debug-iphonesimulator/project.app/Assets.car':
1) Target 'project' (project 'project') has compile command with input '/Users/user/sandbox/project/Resources/buttons.xcassets'
2) That command depends on command in Target 'project' (project 'project'): script phase “[CP] Copy Pods Resources”
The only way I'm able to compile the project is by removing the .xcassets from the target with the obvious downside of having them not available on the build.
PS: This is happening for 2 ObjC projects.
Add below line at the top of your pod file, right after platform :ios
install! 'cocoapods', :disable_input_output_paths => true
Reference
The answer above is only partially correct: yes, this happens because the pod phase produces Assets.car as an output file, which coincides with the output name for your xcassets - hence Multiple commands produce... error: one command being the script phase [CP] Copy Pods Resources and another - your own project's compile command.
But removing Assets.car from output files will cause the build system to fail to see that the script processes the file, thus it skips it (read this for more details). So what we can do is add Assets.car to the input files - this will create a dependency for the script, telling the build system to wait for the file before executing the script.
NB: like the solution above, you will have to do this every time after updating your pods, since [CP] Copy Pods Resources is generated every time you run pod install or pod update
To be sure that all build steps are performed in the correct order, yet as many steps in parallel as possible, Xcode needs to know for every build step which input files it depends on and which output files it will generate.
E.g. if step A depends on an input file that is the output file of step B, step B surely has to run before step A. If neither step requires the output file of the other step, they can both run in parallel.
While several steps can surely depend on the same input file, it cannot be the case that multiple steps produce the same output file as in that case, whichever step runs last would overwrite the output file of whichever step runs first and this means the resulting output file content would be unpredictable and that is an error in a build process that shall created predictable results!
In your case the problem is that your Copy Resources build phase contains one (or more) .xcassets bundle(s). Xcode won't just copy these bundles, instead it will combine them, convert and optimize their content, and create a file called Assets.car that contains the content of all the assets catalogs in your project.
Yet if you integrate a Pod and this Pod also has an asset catalog, exactly the same thing will happen and a second Assets.car file is created and now Xcode has a problem: Two build steps both say they create an Assets.car file. Which one shall win? Which of these two files shall end up in the final application? And what about other steps that depend on this file? After which of the build steps do they have to run? This is a serious problem that Xcode cannot resolve.
There are currently two possibly solutions:
Use frameworks. When you use frameworks instead of static libraries, the resources of Pods don't end up in the resources folder of your main application but in the resources folder of the built framework. All you need to do is to add use_frameworks! to your Podfile, either top level or just for a specific target. The downside is that your overall app size will grow a bit and app start time will increase a bit.
Have the Pod-author fix the Pod. Instead of resources s/he shall use resources_bundle as the Podspec documentation also strongly recommends. Using resources actually has other disadvantages (resource files are not optimized, name conflicts can arise between different Pods), whereas using a resource bundle is safe, regardless if Pods are embedded as static libraries or as dynamic frameworks. Note, though, that it is not enough to just alter the Podspec, all code that loads bundle resources must be adopted to load them from the correct bundle (the name will be known as when using resources_bundle in a Podspec file, you also must give the bundle(s) a name).
There is an on-going bug report for this issue, you can find it here:
https://github.com/CocoaPods/CocoaPods/issues/8122
Yet the problem currently is, that every possible solution other than the two mentioned above would basically be an ugly hack and the Cocoapods developers are not happy implementing ugly hacks. The best solution, as hard as it seems, is probably to not fix that problem at all but to stop supporting resources in Podspec files and make resources_bundle mandatory for Pods that contain own resources.
In your library project, such as "LADetailPage", open Targets' "Build Phases", create a predefined phase named "Copy Files", then drag your *.xcassets to the new phase.
Then the library won't make Assets.car from *.xcassets files when building, instead, cocoapods copies the *.xcassets to your main project which imports the lib, and the main project builds all *.xcassets into a single Assets.car file.
Please check your dependencies if there is some pods use 'resources'(not 'resources_bundle') to link its own xcassets in podspec.
This way has beed deprecated, because its output file name is 'Assets.car'. It is same with your project xcassets' compile output name.
Xcode->File->Workspace settings->Building System-> Legacy Build System
example
I have a sub project that has been developed as dynamic lib and included that sub project into my main project and been set as target dependency.
When I run my main project, .a file for my sub project has been created successfully and the corresponding header files are created in the build directory such as (build/release-iphoneos/include). I have mentioned path using MACRO
In my main project, I mentioned header search path as the same that i mentioned above using MACRO.
But when I try to archive the build it throws the run time error file not found in the import statement
#import <subproject/myfile.h>
But it is getting build and run successfully even though it displays the file not found error in the xcode editor in compile time.
My question is
Is this because of the build directory will be empty while archieving?
I solved the problem as below
1. The header files were private so changed them as public so they are exposed to main project. (To build & run successfully)
2. I copied the header files and created a directory and add them into my main project and set the header search path to point that directory (To archive successfully)
I'm developing an Static Library / iOS Framework (Jeff Verkoeyen way) and I've added CocoaPods for manage dependencies (this is the big difference with other questions about duplicate symbols).
I've been struggling with the "duplicate symbols" problem when a client that use CocoaPods use my static library / framework and a 3rd party library that I'm using too.
I've been reading answers talking about not including 3rd party libraries into a custom static library but I want to do it this way, so that is not an option.
I've found this article (thank you Ryan Arana) that talks about this problem and "the best" solution and I've had to adapt it to my CocoaPods driven Static Library:
1. Create an empty NamespacedDependencies.h in the root of workspace and add it to main project.
2. Add this to the prefix header of the main project (before any include of pods):
#import "NamespacedDependencies.h"
3. Add this hook to Podfile:
post_install do | installer |
environment_header = installer.config.project_pods_root + 'Pods-environment.h'
text = "#import \"NamespacedDependencies.h\"\n\n" + environment_header.read
environment_header.open('w') { |file| file.write(text) }
dummy_class = installer.config.project_pods_root + 'Pods-dummy.m'
text = "#import \"NamespacedDependencies.h\"\n\n" + dummy_class.read
dummy_class.open('w') { |file| file.write(text) }
end
4. Copy Ryan Arana's script to the root and edit the variables.
5. Add a "Run Script Build Phase" to Pods Target with:
./generate_namespace_header.sh
6. Build workspace. At this point I have my NamespacedDependencies.h macros.
7. Comment or remove the "Run Script Build Phase" that It has been created before.
8. Build again.
Problems:
It works but it has problems:
1. Require manual steps. When I add/remove a pod to/from Podfile (and run pod install) I've to clean workspace (iphoneos and iphonesimulator in my case), left NamespacedDependencies.h empty, add the "Run Script Build Phase" (its removed by cocoapods) and start again.
2. I don't know if the post_install hook is ok, I just copied code from somewhere and change it but I'm sure that must be a better way to do this. I can't find documentation about it.
Edited:
I'm using CocoaPods 0.29.0, Xcode 5 and iOS 7
Ryan Arana's script is a slightly modification of the Nimbus' script. The "original" featherless's answer help me a lot. (See Ryan Arana's article)
When I run "pod install", the "Run Script Build Phase" and the NamespacedDependencies.h includes are deleted. This is why I've to create that phase every time I add/remove a pod, and why I've added a hook to add includes.
I add the import to Pods-environment.h because it's imported in the prefix header of each pod. But that configuration could change in future versions so I would like to find another way to do this. I don't know how to add it to each pch anyway. "General" Pod target has no pch so I've to add it to Pods-dummy.m directly.
If I don't comment or remove the "Run Script Build Phase" when NamespacedDependencies.h macros and libPods.a are already created, macros is recreated for the prefixed symbols and everything goes wrong.
I'm trying to create a archive for a app linking to a static library but with no luck.
I can built the app in both release and debug mode just fine. I can even built it for Archive (product->built for->archiving) but it fails miserably when I try to create the archive (products->Archive)
XCode can't seem to find the headers for the Static lib:
In file included from /Data/Code/iPhoneDev/ArchiveTest/ArchiveTestApp/ArchiveTestApp/ArchiveTestAppAppDelegate.m:9:
/Data/Code/iPhoneDev/ArchiveTest/ArchiveTestApp/ArchiveTestApp/ArchiveTestAppAppDelegate.h:10:24: error: DataFetcher.h: No such file or directory
In file included from /Data/Code/iPhoneDev/ArchiveTest/ArchiveTestApp/ArchiveTestApp/ArchiveTestAppAppDelegate.m:9:
/Data/Code/iPhoneDev/ArchiveTest/ArchiveTestApp/ArchiveTestApp/ArchiveTestAppAppDelegate.h:13: error: cannot find protocol declaration for 'DataFetcherDelegate'
Any ideas or suggestions on what I'm missing here?
I ended up roughly following the suggestions in this Questions:
Compile, Build or Archive problems with Xcode 4 (and dependencies)
Create a group call "Indexing headers" in your project
and drag the headers to this group, DO NOT add to any targets when
prompted. This includes any headers inside your dependency
For all dependancies set "Skip Install" build setting to "Yes"
Moving any "Public" headers in Build Phases to "Project" for dependency
Set the Build Setting "Installation Directory" on your Target to
$(LOCAL_APPS_DIR)
The archive was created with no errors with step 1-3, but for it to become a valid app step 4) was needed.
Amazing how half baked XCode4 seems
Here is the situation I have:
ProjectA - Xcode static library project.
ProjectA contains logical code group ExternLib with file ExternLib.h. ExternLib.h itself is in the folder Classes/lib/ExternLib (relative to ProjectA folder). Within ProjectA, I use ExternLib.h simply as: #import "ExternLib.h". This works fine.
Next I have ProjectB. This includes ProjectA as a linked Xcode project. The target has been added correctly etc. However, when I include a file in ProjectB which in turn includes ExternLib.h, upon building ProjectB, I get an error saying that the file ExternLib.h cannot be found.
I have tried adding the path to ExternLib.h to the header search path (all types: relative, absolute, with recursion etc.) but to no avail. I have checked that static library target has the copy headers step and the file ExternLib.h is included in it.
Anybody able to shed some light on how to get around this?
Add a Run Script Build Phase to the target for ExternLib that executes
mkdir -p "${BUILT_PRODUCTS_DIR}ExternLibHeaders"
Add a Copy Files build phase that copies the ExternLib header files into ${BUILT_PRODUCTS_DIR}ExternLibHeaders, and add all of ExternLib's headers into that phase.
In the app target for ProjectB, add ${BUILT_PRODUCTS_DIR}/ExternLibHeaders/ to the Header Search Paths for all configurations.
In Xcode > Preferences > Build, set the Build Products Directory to some common location.
The fourth step is crucial; it ensures that BUILT_PRODUCTS_DIR is the same for both projects.
It's really hard to say what might have gone wrong.
I'd start from scratch with a tutorial on building and using static libraries, and see if any of the steps jog any ideas out of you.