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_header_to_module()   A

Complexity

Conditions 3

Size

Total Lines 11

Duplication

Lines 0
Ratio 0 %

Importance

Changes 1
Bugs 0 Features 0
Metric Value
cc 3
c 1
b 0
f 0
dl 0
loc 11
rs 9.4285
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import os
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from . import PYSIDE, PYSIDE2, PYQT4, PYQT5
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from .QtWidgets import QComboBox
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if PYQT5:
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    from PyQt5.uic import *
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elif PYQT4:
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    from PyQt4.uic import *
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else:
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    __all__ = ['loadUi']
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    # In PySide, loadUi does not exist, so we define it using QUiLoader, and
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    # then make sure we expose that function. This is adapted from qt-helpers
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    # which was released under a 3-clause BSD license:
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    # qt-helpers - a common front-end to various Qt modules
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    #
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    # Copyright (c) 2015, Chris Beaumont and Thomas Robitaille
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    #
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    # All rights reserved.
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    #
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    # Redistribution and use in source and binary forms, with or without
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    # modification, are permitted provided that the following conditions are
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    # met:
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    #
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    #  * Redistributions of source code must retain the above copyright
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    #    notice, this list of conditions and the following disclaimer.
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    #  * Redistributions in binary form must reproduce the above copyright
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    #    notice, this list of conditions and the following disclaimer in the
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    #    documentation and/or other materials provided with the
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    #    distribution.
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    #  * Neither the name of the Glue project nor the names of its contributors
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    #    may be used to endorse or promote products derived from this software
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    #    without specific prior written permission.
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    #
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    # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
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    # IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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    # THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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    # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
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    # CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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    # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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    # PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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    # PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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    # LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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    # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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    # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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    #
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    # Which itself was based on the solution at
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    #
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    # https://gist.github.com/cpbotha/1b42a20c8f3eb9bb7cb8
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    #
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    # which was released under the MIT license:
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    #
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    # Copyright (c) 2011 Sebastian Wiesner <[email protected]>
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    # Modifications by Charl Botha <[email protected]>
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    #
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    # Permission is hereby granted, free of charge, to any person obtaining a
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    # copy of this software and associated documentation files (the "Software"),
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    # to deal in the Software without restriction, including without limitation
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    # the rights to use, copy, modify, merge, publish, distribute, sublicense,
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    # and/or sell copies of the Software, and to permit persons to whom the
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    # Software is furnished to do so, subject to the following conditions:
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    #
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    # The above copyright notice and this permission notice shall be included in
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    # all copies or substantial portions of the Software.
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    #
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    # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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    # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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    # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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    # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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    # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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    # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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    # DEALINGS IN THE SOFTWARE.
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    if PYSIDE:
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        from PySide.QtCore import QMetaObject
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        from PySide.QtUiTools import QUiLoader
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    elif PYSIDE2:
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        from PySide2.QtCore import QMetaObject
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        from PySide2.QtUiTools import QUiLoader
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    class UiLoader(QUiLoader):
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        """
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        Subclass of :class:`~PySide.QtUiTools.QUiLoader` to create the user
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        interface in a base instance.
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        Unlike :class:`~PySide.QtUiTools.QUiLoader` itself this class does not
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        create a new instance of the top-level widget, but creates the user
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        interface in an existing instance of the top-level class if needed.
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        This mimics the behaviour of :func:`PyQt4.uic.loadUi`.
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        """
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        def __init__(self, baseinstance, customWidgets=None):
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            """
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            Create a loader for the given ``baseinstance``.
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            The user interface is created in ``baseinstance``, which must be an
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            instance of the top-level class in the user interface to load, or a
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            subclass thereof.
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            ``customWidgets`` is a dictionary mapping from class name to class
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            object for custom widgets. Usually, this should be done by calling
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            registerCustomWidget on the QUiLoader, but with PySide 1.1.2 on
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            Ubuntu 12.04 x86_64 this causes a segfault.
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            ``parent`` is the parent object of this loader.
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            """
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            QUiLoader.__init__(self, baseinstance)
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            self.baseinstance = baseinstance
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            if customWidgets is None:
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                self.customWidgets = {}
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            else:
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                self.customWidgets = customWidgets
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        def createWidget(self, class_name, parent=None, name=''):
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            """
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            Function that is called for each widget defined in ui file,
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            overridden here to populate baseinstance instead.
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            """
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            if parent is None and self.baseinstance:
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                # supposed to create the top-level widget, return the base
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                # instance instead
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                return self.baseinstance
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            else:
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                # For some reason, Line is not in the list of available
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                # widgets, but works fine, so we have to special case it here.
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                if class_name in self.availableWidgets() or class_name == 'Line':
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                    # create a new widget for child widgets
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                    widget = QUiLoader.createWidget(self, class_name, parent, name)
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                else:
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                    # If not in the list of availableWidgets, must be a custom
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                    # widget. This will raise KeyError if the user has not
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                    # supplied the relevant class_name in the dictionary or if
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                    # customWidgets is empty.
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                    try:
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                        widget = self.customWidgets[class_name](parent)
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                    except KeyError:
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                        raise Exception('No custom widget ' + class_name + ' '
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                                        'found in customWidgets')
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                if self.baseinstance:
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                    # set an attribute for the new child widget on the base
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                    # instance, just like PyQt4.uic.loadUi does.
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                    setattr(self.baseinstance, name, widget)
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                return widget
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    def _header_to_module(header):
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        header = os.path.splitext(header)[0]
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        if '..' in header:
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            raise SyntaxError("custom widget header file name may not contain '..'.")
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        header = header.replace('.', '')
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        while '//' in header:
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            header = header.replace('//', '/')
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        header = header.replace('/', '.')
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        return header
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    def _get_custom_widgets(ui_file):
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        """
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        This function is used to parse a ui file and look for the <customwidgets>
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        section, then automatically load all the custom widget classes.
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        """
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        import sys
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        import importlib
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        from xml.etree.ElementTree import ElementTree
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        # Parse the UI file
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        etree = ElementTree()
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        ui = etree.parse(ui_file)
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        # Get the customwidgets section
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        custom_widgets = ui.find('customwidgets')
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        if custom_widgets is None:
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            return {}
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        custom_widget_classes = {}
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        for custom_widget in custom_widgets.getchildren():
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            cw_class = custom_widget.find('class').text
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            cw_header = custom_widget.find('header').text
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            module = importlib.import_module(_header_to_module(cw_header))
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            custom_widget_classes[cw_class] = getattr(module, cw_class)
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        return custom_widget_classes
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    def loadUi(uifile, baseinstance=None, workingDirectory=None):
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        """
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        Dynamically load a user interface from the given ``uifile``.
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        ``uifile`` is a string containing a file name of the UI file to load.
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        If ``baseinstance`` is ``None``, the a new instance of the top-level
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        widget will be created. Otherwise, the user interface is created within
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        the given ``baseinstance``. In this case ``baseinstance`` must be an
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        instance of the top-level widget class in the UI file to load, or a
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        subclass thereof. In other words, if you've created a ``QMainWindow``
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        interface in the designer, ``baseinstance`` must be a ``QMainWindow``
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        or a subclass thereof, too. You cannot load a ``QMainWindow`` UI file
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        with a plain :class:`~PySide.QtGui.QWidget` as ``baseinstance``.
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        :method:`~PySide.QtCore.QMetaObject.connectSlotsByName()` is called on
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        the created user interface, so you can implemented your slots according
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        to its conventions in your widget class.
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        Return ``baseinstance``, if ``baseinstance`` is not ``None``. Otherwise
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        return the newly created instance of the user interface.
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        """
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        # We parse the UI file and import any required custom widgets
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        customWidgets = _get_custom_widgets(uifile)
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        loader = UiLoader(baseinstance, customWidgets)
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        if workingDirectory is not None:
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            loader.setWorkingDirectory(workingDirectory)
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        widget = loader.load(uifile)
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        QMetaObject.connectSlotsByName(widget)
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        return widget
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