Qt Creator and iOS

Leonardo

Hi. I've been developing an app for Android, now I need to add support for iOS. I would like to keep using Qt Creator, so I can keep a single code base. I'm trying to mix C++ and Objective-C to use some native features or frameworks. I'm a little bit confused about the anatomy of a Qt app for iOS. I've been looking for some article like this one for Android

https://blog.qt.io/blog/2013/07/23/anatomy-of-a-qt-5-for-android-application/

but couldn't find anything. I'm also having trouble coding with Qt Creator. Let's say I have this code:

#include <QtGui>
#include <QtGui/5.5.0/QtGui/qpa/qplatformnativeinterface.h>

#import <UIKit/UIKit.h>
#import <FBSDKCoreKit/FBSDKCoreKit.h>
#import <FBSDKLoginKit/FBSDKLoginKit.h>

void MyController::facebookLogin(){

	QPlatformNativeInterface* nativeInterface = QGuiApplication::platformNativeInterface();

	UIView *view = static_cast<UIView *>(nativeInterface->nativeResourceForWindow("uiview", qApp->topLevelWindows().at(0)));

	UIViewController *qtController = [[view window] rootViewController];

	FBSDKLoginManager *login = [[FBSDKLoginManager alloc] init];
	[login
	  logInWithReadPermissions: @[@"public_profile",@"email"]
			fromViewController: qtController
					   handler:^(FBSDKLoginManagerLoginResult *result, NSError *error) {
	  if (error) {
		NSLog(@"Process error");
	  } else if (result.isCancelled) {
		NSLog(@"Cancelled");
	  } else {
		NSLog(@"Logged in");
	  }
	}];

}

I can compile it, but Qt Creator puts a red underline on every Objective-C code. It cannot parse headers imported from Facebook SDK also.

Is there any way to work with Objective-C on Qt Creator or should I move to XCode? In that case, how can I keep my XCode project synchronized with my .pro file?

Thank you.

SGaist

Hi,

Since you are mixing both you're using Objective-C++ so is your file ending in mm ? Did you add it to OBJECTIVE_SOURCES in your pro file ?

Leonardo

Hi. Yes, I did. Here's part of my pro file:

TEMPLATE = app

QT += qml quick widgets

SOURCES += mycontroller.cpp 
HEADERS += mycontroller.h

ios {

	QMAKE_CXXFLAGS += -std=c++11 -stdlib=libc++ -F$$PWD/ios
	QMAKE_LFLAGS += -stdlib=libc++ -F$$PWD/ios

	OBJECTIVE_SOURCES += mycontroller_ios.mm

	QMAKE_INFO_PLIST = ios/Info.plist

	LIBS += -lz -framework UIKit -framework FBSDKCoreKit -framework FBSDKLoginKit

}

SGaist

Where's the Facebook SDK located ?

Leonardo

Inside the ios folder. I already had a subfolder for the android tree, so I wanted to keep the pattern and created a subfolder for ios. As I said before, I can compile it, so I guess qmake is working properly.

SGaist

Sorry, I may have misunderstood your problem. Did you mean that the you "only" have problem with auto-completion and such with Qt Creator ?

Leonardo

Yes. Check it out:

SGaist

IIRC, you should rather have LIBS += -F $ $PWD/iOS (minus the spaces)

Leonardo

Compilation works, but the editor still highlights Objective-C code... =(

ios {

	QMAKE_CXXFLAGS += -std=c++11 -stdlib=libc++
	QMAKE_LFLAGS += -stdlib=libc++

	OBJECTIVE_SOURCES += mycontroller_ios.mm

	QMAKE_INFO_PLIST = ios/Info.plist

	LIBS += -lz -F$$PWD/ios -framework UIKit -framework FBSDKCoreKit -framework FBSDKLoginKit

}

SGaist

Did you try using the clang code model ?

Leonardo

Hi. What do you mean by that?

SGaist

Qt Creator provides two code models (the beast that analyses your projects and provides all the nice stuff like auto-completion of your classes etc.) The default and the clang implementation that you can activate through the About Plugins menu.

Leonardo

You nailed it!

For those interested:

http://doc.qt.io/qtcreator/creator-clang-codemodel.html

After enabling the plugin, go to

Preferences > C++ > Code Model

I changed both "Objective C" and "Objective C++" to clang. After that, the highlighting is gone.

It seems ok now. I can't test it properly, because I just upgraded to XCode 7 and broke Qt Creator's support for iOS, but it feels like to right solution.

Thank you.

SGaist

What did break ?

Leonardo

Apparently, Qt Creator is not compatible with XCode 7 toolchain. After upgrading, the compiler for iOS went missing.

SGaist

What version of Qt Creator are you using ? IIRC Qt Creator 3.5.1 and Qt 5.5.1 don't suffer from that problem.

Leonardo

I'm using Qt 5.5.0 with Qt Creator 3.4.2. Maybe that's why, but I've already came to terms with using XCode. It works fine.

Thank you.