Using QCocoaNativeContext
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I'm wanting to get the native OpenGL context on macOS but when including
<QtPlatformHeaders/QCocoaNativeContext> I get the following error:In file included from
.../qt-5.12.7/qtbase/include/QtPlatformHeaders/QCocoaNativeContext:1:
.../qt-5.12.7/qtbase/include/QtPlatformHeaders/qcocoanativecontext.h:1:
In file included from
.../qt-5.12.7/qtbase/include/QtPlatformHeaders/../../src/platformheaders/nativecontexts/qcocoanativecontext.h:44:
In file included from
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSOpenGL.h:8:
In file included from
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk/System/Library/Frameworks/AppKit.framework/Headers/AppKitDefines.h:11:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSObjCRuntime.h:492:1:
error: expected unqualified-id
@class NSString, Protocol;Looks like it's including Objective-C stuff that the compiler doesn't like.
This is in a Xcode (11.3) project that was created by CMake.
How do I make this work?
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Hi,
You are going to use Objective-C code, therefore you need to change your file extension to .mm so that the compiler treats it as Objective-C++ code. Then you'll be able to compile it.
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Hi,
You are going to use Objective-C code, therefore you need to change your file extension to .mm so that the compiler treats it as Objective-C++ code. Then you'll be able to compile it.
@SGaist said in Using QCocoaNativeContext:
Hi,
You are going to use Objective-C code, therefore you need to change your file extension to .mm so that the compiler treats it as Objective-C++ code. Then you'll be able to compile it.
I created a myfile.m with #include <QtPlatformHeaders/QCocoaNativeContext> and added that to my project.
Now I get a compilation error: Qt requires C++11 support
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Not .m but .mm
There's a difference between the two. One is for Objective-C and the other for Objective-C++. You want the second one.
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Not .m but .mm
There's a difference between the two. One is for Objective-C and the other for Objective-C++. You want the second one.
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Well, when you want to use native API's like that, you are expected to have that kind of knowledge.
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@SGaist Thanks. Changed to .mm and it compiles now.
I didn't find this information in any of the Qt documentation. Do you know if it is in there somewhere? If not I'll submit a bug report.
@glennr said in Using QCocoaNativeContext:
I didn't find this information in any of the Qt documentation.
There is also no information that a file ending with 'c' is treated as c and 'cpp' as c++ - it's basic knowledge when you want to use a language.
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@glennr said in Using QCocoaNativeContext:
I didn't find this information in any of the Qt documentation.
There is also no information that a file ending with 'c' is treated as c and 'cpp' as c++ - it's basic knowledge when you want to use a language.
@Christian-Ehrlicher said in Using QCocoaNativeContext:
@glennr said in Using QCocoaNativeContext:
I didn't find this information in any of the Qt documentation.
There is also no information that a file ending with 'c' is treated as c and 'cpp' as c++ - it's basic knowledge when you want to use a language.
I wasn't meaning the .m/.mm part. I was referring to the fact that the QtPlatformHeaders/QCocoaNativeContext header can only be included in a .mm file.
Qt is a cross platform C++ framework and presumably its users (who are C++ developers and not necessarily platform experts) expect some sort of insulation from platform issues. In this case it is unavoidable so it would be a courtesy to those non-mac developers to mention in the documentation for QCocoaNativeContext that it is not C++ and can only be included in an Objective-C++ file.
My specific use case for this is that I need a pointer to the OpenGLContext to pass to a third party library. I don't need to access any of the Objective-C++ APIs in my code.
