Objective-C header file not found (AFNetworking.h) [duplicate] - objective-c

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AFNetworking.h file not found
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Closed 1 year ago.
#import <AFNetworking/AFNetworking.h>
I imported AFNetworking.h file to .m file but an error occurred like this:
'AFNetworking/AFNetworking.h' file not found
I deleted pods folder and Podfile.lock, and reinstalled Podfile but didn't solved. What should I do? (I opened the workspace file.)

Linking !== Copying.
there is C style #include ... and Objective-C style #import ...
both work almost the same..
where #import reads the header but does not include again if done once. As this can and does fail sometime (usually because mixing C,C++,Objc,Objc++ in different dialects) we often use #define rules to make sure the enclosed code is read once for sure and not again, which in turn works also when code is included and declared with #include. It would be included but not compiled twice.
#ifndef SOME_HumanReadableFlag_h
#define SOME_HumanReadableFlag_h
// ... your header code here..
#interface XyzObject : FromInheritedClass
#end
#endif
Now why does it matter?
It might happen that a #define rule enclosing the header files content hides the header from the viewpoint of other classes.. This can & does happen often when classes are not properly written with the end developers structure in mind. It might work on the workbench of the developer but not for everyone else implementing it.
Your error clearly tells "File not found .."
So first see what both import/include rules differentiate in general
#import <LibFrameworkName/LibFrameworkName.h>
means you have to link the framework or library, even if you developed one on your own in that project. The rule is relative to your project, LibFrameworkName is a Framework/Lib. Where if found somewhere #include <LibFrameworkName/LibFrameworkName.h> is not correct unless you want to c-style include this framework header into your binarys header, 2) tells you a bit about why..
#import "LibFrameworkName/LibFrameworkName.h"
means you have to copy/offer this header into your project with a subfolder with name LibFrameworkName. Once somewhere declared properly Xcode might find and apply the headers even if declared with the wrong rule later on in that specific class, you should also get a warning in the IDE then. In case of AFNetworking you dont want to copy System SDK Frameworks into your project, also not into third party frameworks unless you know what you do. This rule is relative to the files place in project structure, meaning here it would try to look out for some folder with name LibFrameworkName below the file that carries this rule.
what it says: because the Framework is not linked, the compiler tries to find it with the given name ignoring < & > so as if it where like 2) a file with that folder name, then will not find it and throws the error or warning.
To force the precompiler to parse thru some specific folders we use sometime the header search path to explicit tell where to find it. Widely used and mostly troublesome because it also hides wrongly defined rules to the developer as Xcode skips the still existing wrong import rules in code assuming it knows this headers already. Or it throws warnings while everything is actually fine. Other developers experience trouble then, the file structure and header list don't match at all. So keep in mind, when you can avoid making use of header search path lists, go for it. It also will and should not fix your issue.
'<AFNetworking/AFNetworking.h>' File not found means a Framework module is not known to your project. This header is part of a Framework.
Solution: You have to go to your Projects Settings and scroll down to Frameworks and Libraries, hit [+] below this list. It should open the dialog presenting all SDK from your choosen Project Target and all known Pods or known frameworks of your own project when you developed some. Search for the Framework or Lib by name, click it, hit "Add".. done..
From there - there are some options to get used to it..
Because Linking does not mean Copying into your Resources at compile time by default. Usually Xcode knows it does not have to copy System SDK into a projects Framework Folder, all macUsers have those Frameworks preinstalled on their system of course in the right version.. Linking against some specific folder like ${SOMEFLAGWHEREEVERTHISPOINTSTO}/AFNetworking/AFNetworking.framework/Headers is actually wrong unless someone wanted to overrule the systems framework header and maybe also binary.
So AFNetworking should not appear under Build Phases > Copy Bundle Ressources list but after the process above is done it will appear under Link Binary with Libraries, it might also be placed in Dependencies when Xcode needs to know for some Library/Framework it must have this to compile. Last mentioned option is because you could have a framework that adapts at runtime when some framework is missing or not available. So this Entry helps Xcode to figure out in which sorting it has to compile your stuff.
finding ${PODS_CONFIGURATION_BUILD_DIR}/AFNetworking/AFNetworking.framework/Headers in Header Search Paths there must be something wrong i guess.. because the framework is very likely not copied into the Pods folder. It should be relative to your SDKs folder that come with Xcode. The Linking process told above should fix that and you can erase that entry from your header search path then.

Related

How to add .c and .h files to Atmel Studio 6?

I know there are a lot of questions on this topic, and I've looked through a fair number of them. However I am still having problems.
I started writing a test program for a prototype PCB, and now that it's grown to nearly 1000 lines I'm trying to break it up into libraries that I can use for particular functions.
I thought this would be very simple. Make .c and .h files for each library that I need. I.e. I would have OLED.h and OLED.c for functions that control an OLED display. Copy the appropriate functions/definitions into each file. Then copy these files into the solution in Atmel Studio. I put them into the src folder under the project name.
However, this doesn't work! I get an exceedingly long list of errors. All of the things that are defined in the .h file are apparently undefined as far as the compiler is concerned. I also get many error messages of the type "unknown type name int16_t/uint16_t/uint8_t/etc..." That part is really baffling to me. Why should it matter that functions are in an external library, now the compiler doesn't understand what those data types mean?
So, this is probably a stupid problem to have. I don't want Atmel Studio to control my libraries by wrapping them up in some "library project" or somethig, I want to put them in a folder of my choosing and add them when I need them. I've searched for answers to this problem and I find long tutorials about changing the compiler settings for the project, the linker settings, etc... I tried this tutorial and still no dice: http://www.engblaze.com/tutorial-using-avr-studio-5-with-arduino-projects/#setup
I also can't find a way to add something by right clicking the project and clicking "Add." It wants me to find .a files. The "Add Library" dialog box in Atmel Studio is awful, it seems.
Surely it can't be that convoluted to just add a library to an existing project and have it function normally?! I've used PICs in the past and coming to Atmel I've found horrible documentation and a weird super-slick super-fly whizz bang interface that can't leave well enough alone and obfuscates simple function. What can I do to add these libraries?
UPDATE: Seemed to answer my own question. Turns out I needed to include all of the libraries to recognize data types and whatnot into the .c file. I somehow assumed this only had to be done in the main file but obviously I was mistaken. Adding asf.h seems to work well as it includes all of the MCU specific port definitions/names and all of that. All good for now!
Adding library files to a solution should be simple. Go to the Solution Explorer, right-click on your solution, and go to "Add->Existing Item". If you want to add a pre-existing library and keep it in a separate folder from your solution, click the arrow next to "Add" and choose "Add as link". That saves many headaches due to having a duplicate copy of your library in your solution folder, and files not staying up-to-date.
You are right in saying that you need to include the necessary header files in the .c files where they are used.
The compiler compiles each C file separately, and then links them together at the end, so you got the error unknown typename int_* because the compiler had not seen the relevant header in the context of compiling that C file.
You also seem to be in some confusion as to the difference between definition and declaration.
A function is:
Declared in the header file. This means there is a function prototype, e.g. int some_func(char some_var); which tells the compiler that the function exists, but does not tell it what it is. This is necessary because the compiler only looks at one C file at a time, so needs to be told that other functions exist.
Defined in the C file.This is the actual function body, i.e. int some_func(char some_var) { do_stuff(some_var); }. After compilation of each individual C file in isolation, the linker is called to put all the pieces together and give you your final binary, which you flash to the device.
A function can be (and must be) defined only once, but may be declared many times - even in the same file, so long as the declarations are not conflicting.

Explain these three things about #import in Objective-C: quotation marks, less than and greater than (<,>) symbols, and subdirectories

I want to archive my project but can't because of this nice little error (which leads down a futile rabbit hole in other searched questions and google group discussions): 'RestKit/RestKit.h' file not found.
The reason? This little line (which happens to compile just fine even when building for the freakin' archiving):
#import "RestKit/RestKit.h"
Which makes me ask:
What do the quotation marks do compared to the < and > symbols? For example, I tried <RestKit/RestKit.h>. It didn't work, but I don't know why.
What effect does the / have in the import? In my case, RestKit is located within an SDK in my project. That puts it two tiers into my project (TopProj > SDK > RestKit in SDK). How does the slash affect things?
Thanks!
< and > In #import lines makes the preprocessor search for those files in system directories (/usr/include, etc. You can also define custom search paths in Header Search Paths under Build Settings). Use this for files like UIKit/UIKit.h, which is an Apple framework.
This won't work for files added locally, for example, RestKit, which is why you instead use "RestKit/RestKit.h", as that makes the preprocessor search locally for that file. This is for any file you create or add to your project.
The slash in "RestKit/RestKit.h" is showing that the RestKit.h file is located in the RestKit directory.

xcode import filename collision

Let's say I'm trying to use one and only one 3rd-party library in an xcode project - a pretty typical scenario, seemingly harmless.
I plug in the path location of my include files to the project's "header file search path" setting. I haven't even modified any code to make use of the code in the library yet.
It turns out that the project couldn't compile.
Xcode complained something like "Cannot find interface declaration for NSObject", which is pretty absurd. By examining the Build Result, the complained error comes from a header file of the 3rd-party library - it looks something like
So it is indicated in the Build Result that xcode is mistaken that Foundation.h is referring to the assert.h of that 3rd-party library instead of the iOS' built-in assert.h (4th sub-item)
Is there a way to fix the collision of the file names of #import include files?
(Needless to say, I'm new to obj-c -___-)

Adding GLM to project in Xcode 4

I am trying to add GLM to a project in Xcode 4, but I cannot get it to compile. I have added the glm files to my project through the add files dialog.
I get a lexical/preprocessor issue and Xcode cannot find the file <cmath>.
I am not sure what I need to tweak to get this to build.
I have seen How do I add OpenGL Mathematics (GLM) to Xcode 4? already.
All you need to do is add the files to the project and #import "glm.hpp" (for Objective-C++; for simple C++ it should just be #include "glm.hpp").
A couple things to be careful of:
The OpenGL Mathematics library, when you download it, comes with a bunch of stuff you don't need (test code, extraneous utilities). Adding these to your project will result in compile errors which I could not get rid of. The only directory you need is the glm/ directory; you can delete the test/, util/, doc/, and bench/ directories. If you were trying to follow "How do I add OpenGL Mathematics (GLM) to Xcode 4?" and were still having problems, this may be the thing which was tripping you up.
The OpenGL Mathematics documentation tells you to include the or files. In Xcode 4, you should include them like "glm.hpp" or "*.hpp". Xcode will find the files no matter where in the project they are. Supposedly you can add a user-defined build setting "USE_HEADERMAP" and set it to "NO" to disable this, but I didn't have any luck with that.
And, just in case, note that your code files using the OpenGL Mathematics library must be Objective C++ files (ending in ".mm"), not the default/plain Objective C files (ending in ".m"). It is very much a C++ library after all... :-)
I hope that help. I was just working through this myself, and I haven't had the chance to really push this (e.g. I've basically just added a mat4 object or two and made sure things still compiled), but it seems to be working.
I ran into the same problem and I solved it remaning my ViewController.m to ViewController.mm. Change the extension to .mm tells XCode that the file may contain C++ code inside. The article Write Object-C Code explains this in the Classes and Objects section.

Not possible to create a framework with no executable code?

Just stumbled into something strange with Xcode 4 and Cocoa frameworks. I've a meta-framework that is essentially a .h file with constants needed by a number of other frameworks I've created. I'm capable of creating and building the framework but every time I try to include it in a project Xcode would throw a hissy fit during the build phase, saying it couldn't find the framework, even though the .framework folder was there and the .h file was set to be publicly visible.
After many a hours of running in circles I decided to throw in a .m and corresponding .h files, just so I could have something binary in there and now Xcode is happy as Larry.
Can someone explain this behaviour to me? Why do I need a useless executable to make Xcode see my framework?
The hissy fit is presumably coming from the linker. (Always post your error messages! Guessing isn’t that much fun.) As far as the linker is concerned, the binary is the framework. If you just want the header, you can include the framework in your search paths and #include the header without linking to the framework.