4 files changed, 219 insertions, 2 deletions
diff --git a/silx/gui/utils/glutils.py b/silx/gui/utils/glutils.py
index fca9a32..83cfd89 100644
--- a/silx/gui/utils/glutils.py
+++ b/silx/gui/utils/glutils.py
@@ -27,6 +27,13 @@
 
 import os
 import sys
+
+if __name__ == "__main__":
+    # When run as a script, remove directory from sys.path
+    # This avoids other script in same directory to override Python modules
+    if os.path.abspath(sys.path[0]) == os.path.abspath(os.path.dirname(__file__)):
+        sys.path.pop(0)
+
 import subprocess
 from silx.gui import qt
 
diff --git a/silx/gui/utils/matplotlib.py b/silx/gui/utils/matplotlib.py
new file mode 100644
index 0000000..484e01a
--- /dev/null
+++ b/silx/gui/utils/matplotlib.py
@@ -0,0 +1,71 @@
+# coding: utf-8
+# /*##########################################################################
+#
+# Copyright (c) 2016-2020 European Synchrotron Radiation Facility
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ###########################################################################*/
+
+from __future__ import absolute_import
+
+"""This module initializes matplotlib and sets-up the backend to use.
+
+It MUST be imported prior to any other import of matplotlib.
+
+It provides the matplotlib :class:`FigureCanvasQTAgg` class corresponding
+to the used backend.
+"""
+
+__authors__ = ["T. Vincent"]
+__license__ = "MIT"
+__date__ = "02/05/2018"
+
+
+from pkg_resources import parse_version
+import matplotlib
+
+from .. import qt
+
+
+def _matplotlib_use(backend, force):
+    """Wrapper of `matplotlib.use` to set-up backend.
+
+     It adds extra initialization for PySide and PySide2 with matplotlib < 2.2.
+    """
+    # This is kept for compatibility with matplotlib < 2.2
+    if parse_version(matplotlib.__version__) < parse_version('2.2'):
+        if qt.BINDING == 'PySide':
+            matplotlib.rcParams['backend.qt4'] = 'PySide'
+        if qt.BINDING == 'PySide2':
+            matplotlib.rcParams['backend.qt5'] = 'PySide2'
+
+    matplotlib.use(backend, force=force)
+
+
+if qt.BINDING in ('PyQt4', 'PySide'):
+    _matplotlib_use('Qt4Agg', force=False)
+    from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg  # noqa
+
+elif qt.BINDING in ('PyQt5', 'PySide2'):
+    _matplotlib_use('Qt5Agg', force=False)
+    from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg  # noqa
+
+else:
+    raise ImportError("Unsupported Qt binding: %s" % qt.BINDING)
diff --git a/silx/gui/utils/signal.py b/silx/gui/utils/signal.py
new file mode 100644
index 0000000..359f5cc
--- /dev/null
+++ b/silx/gui/utils/signal.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python
+# coding: utf-8
+# /*##########################################################################
+#
+# Copyright (c) 2012 University of North Carolina at Chapel Hill, Luke Campagnola
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ###########################################################################*/
+"""This module contains utils relative to qt Signal
+"""
+
+from silx.gui import qt
+import weakref
+from time import time
+from silx.gui.utils import concurrent
+
+__all__ = ['SignalProxy']
+__authors__ = ['L. Campagnola', 'M. Liberty']
+__license__ = "MIT"
+
+
+class SignalProxy(qt.QObject):
+    """
+    This peace of code come from pyqtgraph
+    Object which collects rapid-fire signals and condenses them
+    into a single signal or a rate-limited stream of signals.
+    Used, for example, to prevent a SpinBox from generating multiple
+    signals when the mouse wheel is rolled over it.
+
+    Emits sigDelayed after input signals have stopped for a certain period of time.
+    """
+
+    sigDelayed = qt.Signal(object)
+
+    def __init__(self, signal, delay=0.3, rateLimit=0, slot=None):
+        """Initialization arguments:
+        signal - a bound Signal or pyqtSignal instance
+        delay - Time (in seconds) to wait for signals to stop before emitting (default 0.3s)
+        slot - Optional function to connect sigDelayed to.
+        rateLimit - (signals/sec) if greater than 0, this allows signals to stream out at a
+                    steady rate while they are being received.
+        """
+
+        qt.QObject.__init__(self)
+        signal.connect(self.signalReceived)
+        self.signal = signal
+        self.delay = delay
+        self.rateLimit = rateLimit
+        self.args = None
+        self.timer = qt.QTimer()
+        self.timer.timeout.connect(self.flush)
+        self.blockSignal = False
+        self.slot = weakref.ref(slot)
+        self.lastFlushTime = None
+        if slot is not None:
+            self.sigDelayed.connect(slot)
+
+    def setDelay(self, delay):
+        self.delay = delay
+
+    def signalReceived(self, *args):
+        """Received signal. Cancel previous timer and store args to be forwarded later."""
+        if self.blockSignal:
+            return
+        self.args = args
+        if self.rateLimit == 0:
+            concurrent.submitToQtMainThread(self.timer.stop)
+            concurrent.submitToQtMainThread(self.timer.start, (self.delay * 1000) + 1)
+        else:
+            now = time()
+            if self.lastFlushTime is None:
+                leakTime = 0
+            else:
+                lastFlush = self.lastFlushTime
+                leakTime = max(0, (lastFlush + (1.0 / self.rateLimit)) - now)
+
+            concurrent.submitToQtMainThread(self.timer.stop)
+            concurrent.submitToQtMainThread(self.timer.start, (min(leakTime, self.delay) * 1000) + 1)
+            # self.timer.stop()
+            # self.timer.start((min(leakTime, self.delay) * 1000) + 1)
+
+    def flush(self):
+        """If there is a signal queued up, send it now."""
+        if self.args is None or self.blockSignal:
+            return False
+        args, self.args = self.args, None
+        concurrent.submitToQtMainThread(self.timer.stop)
+        self.lastFlushTime = time()
+        # self.emit(self.signal, *self.args)
+        concurrent.submitToQtMainThread(self.sigDelayed.emit, args)
+        # self.sigDelayed.emit(args)
+        return True
+
+    def disconnect(self):
+        self.blockSignal = True
+        try:
+            self.signal.disconnect(self.signalReceived)
+        except:
+            pass
+        try:
+            self.sigDelayed.disconnect(self.slot)
+        except:
+            pass
+
+
+if __name__ == '__main__':
+    app = qt.QApplication([])
+    win = qt.QMainWindow()
+    spin = qt.QSpinBox()
+    win.setCentralWidget(spin)
+    win.show()
+
+
+    def fn(*args):
+        print("Raw signal:", args)
+
+
+    def fn2(*args):
+        print("Delayed signal:", args)
+
+
+    spin.valueChanged.connect(fn)
+    # proxy = proxyConnect(spin, QtCore.SIGNAL('valueChanged(int)'), fn)
+    proxy = SignalProxy(spin.valueChanged, delay=0.5, slot=fn2)
diff --git a/silx/gui/utils/testutils.py b/silx/gui/utils/testutils.py
index c086657..30b9e34 100644
--- a/silx/gui/utils/testutils.py
+++ b/silx/gui/utils/testutils.py
@@ -142,8 +142,6 @@ class TestCaseQt(unittest.TestCase):
     @classmethod
     def tearDownClass(cls):
         sys.excepthook = cls._oldExceptionHook
-        if cls._qapp is not None:
-            cls._qapp = None
 
     def setUp(self):
         """Get the list of existing widgets."""