Building with MOC files using GYP instead of QMake?

Question

By removing the moc generation step from QMake I no longer have to rely on QtCreator. At the moment I am using a custom script to generate/update Qt moc files before generating makefiles via GYP in eclipse. Does anyone know how to add moc as build rules to GYP so I can consolidate this step?

At the moment I have the script as a build rule inside of eclipse running every-time but I would like to avoid this approach by having GYP generate a makefile with the moc rules already inside of it like QMake does.

Links of interest:

Reference to developing Qt with GYP: https://groups.google.com/group/gyp-developer/browse_thread/thread/42cfb9902b86d715/b17701d9a6805671?show_docid=b17701d9a6805671

GYP Homepage: http://code.google.com/p/gyp/

QMake Homepage: http://qt-project.org/doc/qt-4.8/qmake-manual.html

My current moc script:

#!/bin/bash
MOC="/path/to/Qt/4.8.1/gcc/bin/moc"
SRC_DIR="/path/to/project"

$MOC $SRC_DIR/SkDebuggerUI.h -o $SRC_DIR/moc_SkDebuggerUI.cpp
$MOC $SRC_DIR/SkQtWidget.h -o $SRC_DIR/moc_SkQtWidget.cpp

Answer 1

I had exactly the same question. Instead of including a separate step with moc script, I added the following lines into my .gyp file.

'conditions': [
    ['OS=="linux"': {
        'sources': [
            'your other source code files',
            '<!(moc numerickeypad.h -o moc_numerickeypad.cpp && echo moc_numerickeypad.cpp)',
        ],
    }],
],

I didn't try it on other operating systems, but I think you can do it on other systems similarly. Let me know, if you have figured better ways.

Answer 2

I just went through this, and while it's not perfect, it's workable. I did the following:

• Made a separate 'target' for generating the mocs
• Had that target only have the .h files that we want to run moc on as 'sources'
• Exposed the generated .cpp files as a direct_dependent_settings, so their sources get compiled in dependent targets
• Build a 'rule' to run moc on each of the header files in the 'sources' list.
• Had my executable depend on that target

It looks like this:

'targets':
[
{
    'target_name': 'editor_generate_mocs',
    'type': 'none',
    'sources': 
        [
            'src/editorwindow.h',
        ],

    'direct_dependent_settings':
        {
            'sources':
            [
                '<(SHARED_INTERMEDIATE_DIR)/editorwindow_moc.cpp',
            ]
        },
    'rules':
        [
            {
                'rule_name': 'generate_qt_mocs_rule',
                'extension': '.h',
                'msvs_cygwin_shell' : 0, # Don't run cygwin set_env to run a command.
                'inputs':
                    [
                        '>(qt_dir)/bin/moc.exe',
                    ],
                'outputs':
                    [
                        '<(SHARED_INTERMEDIATE_DIR)/<(RULE_INPUT_ROOT)_moc.cpp',
                    ],
                'action':
                    [
                        '>(qt_dir)/bin/moc.exe',
                        '--compiler-flavor', 'msvc',
                        '<(RULE_INPUT_PATH)',
                        '-o', '<(SHARED_INTERMEDIATE_DIR)/<(RULE_INPUT_ROOT)_moc.cpp'
                    ],
                'message': '<(SHARED_INTERMEDIATE_DIR)/<(RULE_INPUT_ROOT)_moc.cpp'
            }
        ]
    },
# ..., rest of my targets
}
]