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Runtime error for Qt application for ios created using CMake

Hi stackoverflowers :)

If I build a sample Qt / qmake sample (in my case, an analog clock ) and deploy it on a device with iOS 7.1 everything goes smoothly: the application works perfectly on the device. Chapeau - The people at digia have done a great job integrating ios tools into the Qt workflow.

However, if I translate the qmake project into a CMake project, things will not be so smooth. I added an example of an analog clock from Qt-5.3.1 (see below), where I added CMakeLists.txt and a script that runs CMake to create an Xcode project for iOS. The project compiles and even links (I had to add some additional link libraries, see the CMake source file). Yay

But here's the catch: the application crashes at runtime with the following error message:

Error: Failed to load the plug-in platform "ios"

As a comment, this says that using the project parameters, you must "force download" libqios. This did not improve the situation, but only the error message changed to:

Error: you create QApplication before calling UIApplicationMain. If you are writing a native iOS application and want to use Qt as part of the application, a good place to create QApplication is from within the 'applicationDidFinishLaunching' inside your UIApplication delegate.

I have two questions:

  • - , ? , qmake ( ios mkspecs) . CMake?
  • libs (harfbuzzng, qios, libpng iOS) ? find_package (Qt5...) ?

- zip , Qt-CMake. Qt, , - Qt-5.3.1 iOS.

. , qmake , Qt. Qt: //Qt//// .

+4
1

CMake Qt iOS. , Google, , qmake. , CMake.

, . , , :

  • CMake ios. . Cmake/toolchain/ios.toolchain.cmake . CMake . ( , , , Google). CMake (. ).

  • , (iOS). . , Info.plist.in, CMake.

  • 1: CMake. - find_package(Qt5 ...) . , - .

  • 2: libqios, iOS. CMake:

    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -force_load ${YOUR_QT_ROOT_PATH}/plugins/platforms/libqios.a" )

  • 3: Info.plist.in. . stackoverflow.

    <key>UIMainStoryboardFile</key> <string>main</string>

  • 4: : iOS main() "C". -, Qt main , qtmn(). qmake script: /qt/root/path/mkspecs/macx -ios-clang/rename_main.sh. . main:

    // Replace... int main(int argc, char *argv[])

    // ... with this line: extern "C" int qtmn(int argc, char *argv[])

, , , . , build_ios.sh xcodeproj, .

. , XCode (5.1.1 ) ( CMakeLists.txt!). , (. ) , OpenCV, iOS, . , : , libpng, OpenCV.

, .

+5

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