You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

177 lines
6.4 KiB
Python

"""
Qt binding and backend selector.
The selection logic is as follows:
- if any of PyQt5, PySide2, PyQt4 or PySide have already been imported
(checked in that order), use it;
- otherwise, if the QT_API environment variable (used by Enthought) is set, use
it to determine which binding to use (but do not change the backend based on
it; i.e. if the Qt5Agg backend is requested but QT_API is set to "pyqt4",
then actually use Qt5 with PyQt5 or PySide2 (whichever can be imported);
- otherwise, use whatever the rcParams indicate.
"""
from distutils.version import LooseVersion
import os
import sys
from matplotlib import rcParams
QT_API_PYQT5 = "PyQt5"
QT_API_PYSIDE2 = "PySide2"
QT_API_PYQTv2 = "PyQt4v2"
QT_API_PYSIDE = "PySide"
QT_API_PYQT = "PyQt4" # Use the old sip v1 API (Py3 defaults to v2).
QT_API_ENV = os.environ.get("QT_API")
# Mapping of QT_API_ENV to requested binding. ETS does not support PyQt4v1.
# (https://github.com/enthought/pyface/blob/master/pyface/qt/__init__.py)
_ETS = {"pyqt5": QT_API_PYQT5, "pyside2": QT_API_PYSIDE2,
"pyqt": QT_API_PYQTv2, "pyside": QT_API_PYSIDE,
None: None}
# First, check if anything is already imported.
if "PyQt5.QtCore" in sys.modules:
QT_API = QT_API_PYQT5
elif "PySide2.QtCore" in sys.modules:
QT_API = QT_API_PYSIDE2
elif "PyQt4.QtCore" in sys.modules:
QT_API = QT_API_PYQTv2
elif "PySide.QtCore" in sys.modules:
QT_API = QT_API_PYSIDE
# Otherwise, check the QT_API environment variable (from Enthought). This can
# only override the binding, not the backend (in other words, we check that the
# requested backend actually matches).
elif rcParams["backend"] in ["Qt5Agg", "Qt5Cairo"]:
if QT_API_ENV in ["pyqt5", "pyside2"]:
QT_API = _ETS[QT_API_ENV]
else:
QT_API = None
elif rcParams["backend"] in ["Qt4Agg", "Qt4Cairo"]:
if QT_API_ENV in ["pyqt4", "pyside"]:
QT_API = _ETS[QT_API_ENV]
else:
QT_API = None
# A non-Qt backend was selected but we still got there (possible, e.g., when
# fully manually embedding Matplotlib in a Qt app without using pyplot).
else:
try:
QT_API = _ETS[QT_API_ENV]
except KeyError:
raise RuntimeError(
"The environment variable QT_API has the unrecognized value {!r};"
"valid values are 'pyqt5', 'pyside2', 'pyqt', and 'pyside'")
def _setup_pyqt5():
global QtCore, QtGui, QtWidgets, __version__, is_pyqt5, \
_isdeleted, _getSaveFileName
if QT_API == QT_API_PYQT5:
from PyQt5 import QtCore, QtGui, QtWidgets
import sip
__version__ = QtCore.PYQT_VERSION_STR
QtCore.Signal = QtCore.pyqtSignal
QtCore.Slot = QtCore.pyqtSlot
QtCore.Property = QtCore.pyqtProperty
_isdeleted = sip.isdeleted
elif QT_API == QT_API_PYSIDE2:
from PySide2 import QtCore, QtGui, QtWidgets, __version__
import shiboken2
def _isdeleted(obj): return not shiboken2.isValid(obj)
else:
raise ValueError("Unexpected value for the 'backend.qt5' rcparam")
_getSaveFileName = QtWidgets.QFileDialog.getSaveFileName
def is_pyqt5():
return True
def _setup_pyqt4():
global QtCore, QtGui, QtWidgets, __version__, is_pyqt5, \
_isdeleted, _getSaveFileName
def _setup_pyqt4_internal(api):
global QtCore, QtGui, QtWidgets, \
__version__, is_pyqt5, _getSaveFileName
# List of incompatible APIs:
# http://pyqt.sourceforge.net/Docs/PyQt4/incompatible_apis.html
_sip_apis = ["QDate", "QDateTime", "QString", "QTextStream", "QTime",
"QUrl", "QVariant"]
try:
import sip
except ImportError:
pass
else:
for _sip_api in _sip_apis:
try:
sip.setapi(_sip_api, api)
except ValueError:
pass
from PyQt4 import QtCore, QtGui
import sip # Always succeeds *after* importing PyQt4.
__version__ = QtCore.PYQT_VERSION_STR
# PyQt 4.6 introduced getSaveFileNameAndFilter:
# https://riverbankcomputing.com/news/pyqt-46
if __version__ < LooseVersion("4.6"):
raise ImportError("PyQt<4.6 is not supported")
QtCore.Signal = QtCore.pyqtSignal
QtCore.Slot = QtCore.pyqtSlot
QtCore.Property = QtCore.pyqtProperty
_isdeleted = sip.isdeleted
_getSaveFileName = QtGui.QFileDialog.getSaveFileNameAndFilter
if QT_API == QT_API_PYQTv2:
_setup_pyqt4_internal(api=2)
elif QT_API == QT_API_PYSIDE:
from PySide import QtCore, QtGui, __version__, __version_info__
import shiboken
# PySide 1.0.3 fixed the following:
# https://srinikom.github.io/pyside-bz-archive/809.html
if __version_info__ < (1, 0, 3):
raise ImportError("PySide<1.0.3 is not supported")
def _isdeleted(obj): return not shiboken.isValid(obj)
_getSaveFileName = QtGui.QFileDialog.getSaveFileName
elif QT_API == QT_API_PYQT:
_setup_pyqt4_internal(api=1)
else:
raise ValueError("Unexpected value for the 'backend.qt4' rcparam")
QtWidgets = QtGui
def is_pyqt5():
return False
if QT_API in [QT_API_PYQT5, QT_API_PYSIDE2]:
_setup_pyqt5()
elif QT_API in [QT_API_PYQTv2, QT_API_PYSIDE, QT_API_PYQT]:
_setup_pyqt4()
elif QT_API is None:
if rcParams["backend"] == "Qt4Agg":
_candidates = [(_setup_pyqt4, QT_API_PYQTv2),
(_setup_pyqt4, QT_API_PYSIDE),
(_setup_pyqt4, QT_API_PYQT),
(_setup_pyqt5, QT_API_PYQT5),
(_setup_pyqt5, QT_API_PYSIDE2)]
else:
_candidates = [(_setup_pyqt5, QT_API_PYQT5),
(_setup_pyqt5, QT_API_PYSIDE2),
(_setup_pyqt4, QT_API_PYQTv2),
(_setup_pyqt4, QT_API_PYSIDE),
(_setup_pyqt4, QT_API_PYQT)]
for _setup, QT_API in _candidates:
try:
_setup()
except ImportError:
continue
break
else:
raise ImportError("Failed to import any qt binding")
else: # We should not get there.
raise AssertionError("Unexpected QT_API: {}".format(QT_API))
# These globals are only defined for backcompatibility purposes.
ETS = dict(pyqt=(QT_API_PYQTv2, 4), pyside=(QT_API_PYSIDE, 4),
pyqt5=(QT_API_PYQT5, 5), pyside2=(QT_API_PYSIDE2, 5))
QT_RC_MAJOR_VERSION = 5 if is_pyqt5() else 4