Python PyQt5 模块，QtGui() 实例源码

def __init__(self, package):
        UIParser.__init__(self, QtCore, QtGui, QtWidgets, LoaderCreatorPolicy(package))

def import_pyqt5():
    """
    Import PyQt5

    ImportErrors raised within this function are non-recoverable
    """
    from PyQt5 import QtGui, QtCore, QtSvg

    # Alias PyQt-specific functions for PySide compatibility.
    QtCore.Signal = QtCore.pyqtSignal
    QtCore.Slot = QtCore.pyqtSlot

    return QtCore, QtGui, QtSvg, QT_API_PYQT5

def __init__(self, package):
        UIParser.__init__(self, QtCore, QtGui, QtWidgets, LoaderCreatorPolicy(package))

def has_binding(api):
    """Safely check for PyQt4 or PySide, without importing
       submodules

       Parameters
       ----------
       api : str [ 'pyqtv1' | 'pyqt' | 'pyside' | 'pyqtdefault']
            Which module to check for

       Returns
       -------
       True if the relevant module appears to be importable
    """
    # we can't import an incomplete pyside and pyqt4
    # this will cause a crash in sip (#1431)
    # check for complete presence before importing
    module_name = {QT_API_PYSIDE: 'PySide',
                   QT_API_PYQT: 'PyQt4',
                   QT_API_PYQTv1: 'PyQt4',
                   QT_API_PYQT_DEFAULT: 'PyQt4',
                   QT_API_PYQT5: 'PyQt5',
                   }
    module_name = module_name[api]

    import imp
    try:
        #importing top level PyQt4/PySide module is ok...
        mod = __import__(module_name)
        #...importing submodules is not
        imp.find_module('QtCore', mod.__path__)
        imp.find_module('QtGui', mod.__path__)
        imp.find_module('QtSvg', mod.__path__)

        #we can also safely check PySide version
        if api == QT_API_PYSIDE:
            return check_version(mod.__version__, '1.0.3')
        else:
            return True
    except ImportError:
        return False

def import_pyqt4(version=2):
    """
    Import PyQt4

    Parameters
    ----------
    version : 1, 2, or None
      Which QString/QVariant API to use. Set to None to use the system
      default

    ImportErrors raised within this function are non-recoverable
    """
    # The new-style string API (version=2) automatically
    # converts QStrings to Unicode Python strings. Also, automatically unpacks
    # QVariants to their underlying objects.
    import sip

    if version is not None:
        sip.setapi('QString', version)
        sip.setapi('QVariant', version)

    from PyQt4 import QtGui, QtCore, QtSvg

    if not check_version(QtCore.PYQT_VERSION_STR, '4.7'):
        raise ImportError("IPython requires PyQt4 >= 4.7, found %s" %
                          QtCore.PYQT_VERSION_STR)

    # Alias PyQt-specific functions for PySide compatibility.
    QtCore.Signal = QtCore.pyqtSignal
    QtCore.Slot = QtCore.pyqtSlot

    # query for the API version (in case version == None)
    version = sip.getapi('QString')
    api = QT_API_PYQTv1 if version == 1 else QT_API_PYQT
    return QtCore, QtGui, QtSvg, api

def import_pyside():
    """
    Import PySide

    ImportErrors raised within this function are non-recoverable
    """
    from PySide import QtGui, QtCore, QtSvg  # @UnresolvedImport
    return QtCore, QtGui, QtSvg, QT_API_PYSIDE