# -*- coding: utf-8 -*-
# /***************************************************************************
# Name : RangeSlider
# Description : A slider for ranges
# Date : Jun 20, 2012
# copyright : (C) 2012 by Giuseppe Sucameli
# email : brush.tyler@gmail.com
#
# the code is based on RangeSlider by phil
# (see https://svn.enthought.com/enthought/browser/TraitsBackendQt/trunk/enthought/traits/ui/qt4/extra/range_slider.py) licensed under GPLv2
# ***************************************************************************/
# /**************************************************************************
# * *
# * This program is free software; you can redistribute it and/or modify *
# * it under the terms of the GNU General Public License as published by *
# * the Free Software Foundation; either version 2 of the License, or *
# * (at your option) any later version. *
# * *
# ***************************************************************************/
from PyQt5 import QtCore
from PyQt5 import QtGui
from PyQt5 import QtWidgets
[docs]class RangeSlider(QtWidgets.QSlider):
""" A slider for ranges.
This class provides a dual-slider for ranges, where there is a defined
maximum and minimum, as is a normal slider, but instead of having a
single slider value, there are 2 slider values.
This class emits the same signals as the QSlider base class, with the
exception of valueChanged.
In addition, two new signals are emitted to catch the movement of
each handle, lowValueChanged(int) and highValueChanged(int).
"""
highValueChanged = QtCore.pyqtSignal(int)
lowValueChanged = QtCore.pyqtSignal(int)
[docs] def __init__(self, *args):
super(RangeSlider, self).__init__(*args)
self._low = self.minimum()
self._high = self.maximum()
self.pressed_control = QtWidgets.QStyle.SC_None
self.hover_control = QtWidgets.QStyle.SC_None
self.click_offset = 0
# -1 for the low, 1 for the high, 0 for both
self.active_slider = -1
[docs] def lowValue(self):
return self._low
[docs] def setLowValue(self, low):
if low < self.minimum():
low = self.minimum()
if low == self._low:
return
self._low = low
self.update()
if self.hasTracking():
self.lowValueChanged.emit(self._low)
[docs] def highValue(self):
return self._high
[docs] def setHighValue(self, high):
if high > self.maximum():
high = self.maximum()
if high == self._high:
return
self._high = high
self.update()
if self.hasTracking():
self.highValueChanged.emit(self._high)
[docs] def paintEvent(self, event):
# based on http://qt.gitorious.org/qt/qt/blobs/master/src/gui/widgets/qslider.cpp
painter = QtGui.QPainter(self)
style = QtWidgets.QApplication.style()
for i, value in enumerate([self._low, self._high]):
opt = QtWidgets.QStyleOptionSlider()
self.initStyleOption(opt)
gr = style.subControlRect(style.CC_Slider, opt, style.SC_SliderGroove, self)
sr = style.subControlRect(style.CC_Slider, opt, style.SC_SliderHandle, self)
if self.orientation() == QtCore.Qt.Horizontal:
handle_length = sr.width()
slider_length = gr.width()
slider_min = gr.x()
slider_max = gr.right() - handle_length + 1
else:
handle_length = sr.height()
slider_length = gr.height()
slider_min = gr.y()
slider_max = gr.bottom() - handle_length + 1
opt.subControls = QtWidgets.QStyle.SC_SliderGroove | QtWidgets.QStyle.SC_SliderHandle
# draw the first slider with inverted appearance, then the second
# slider drawn on top of the existing ones
if i == 0:
if self.orientation() == QtCore.Qt.Horizontal:
opt.upsideDown = not self.invertedAppearance()
else:
opt.upsideDown = self.invertedAppearance()
if self.orientation() == QtCore.Qt.Horizontal:
opt.sliderValue = value - self.minimum()
opt.sliderPosition = self.minimum() + (self.maximum() - value)
opt.rect.setX(slider_min)
opt.rect.setWidth(slider_length)
else:
opt.rect.setY(slider_min)
opt.rect.setHeight(slider_length)
else:
# do not highlight the second part when has focus to avoid
# drawing of partially overlapped semi-transparent backgrounds
opt.state &= ~QtWidgets.QStyle.State_HasFocus
opt.sliderValue = 0
opt.sliderPosition = self.minimum()
if self.orientation() == QtCore.Qt.Horizontal:
opt.upsideDown = self.invertedAppearance()
pos = style.sliderPositionFromValue(0, self.maximum()-self.minimum(),
value-self.minimum(), slider_max - slider_min - 4,
opt.upsideDown)
opt.rect.setX(pos + 3)
opt.rect.setWidth(slider_max - pos + handle_length - 3)
else:
opt.upsideDown = not self.invertedAppearance()
pos = style.sliderPositionFromValue(0, self.maximum()-self.minimum(),
self.maximum()-value, slider_max - slider_min - 4,
opt.upsideDown)
opt.rect.setY(slider_min-1)
opt.rect.setHeight(slider_min + slider_length - pos - 2)
if self.tickPosition() != self.NoTicks:
opt.subControls |= QtWidgets.QStyle.SC_SliderTickmarks
if self.pressed_control:
opt.activeSubControls = self.pressed_control
opt.state |= QtWidgets.QStyle.State_Sunken
else:
opt.activeSubControls = self.hover_control
style.drawComplexControl(QtWidgets.QStyle.CC_Slider, opt, painter, self)
[docs] def mousePressEvent(self, event):
event.accept()
style = QtWidgets.QApplication.style()
button = event.button()
# In a normal slider control, when the user clicks on a point in the
# slider's total range, but not on the slider part of the control the
# control would jump the slider value to where the user clicked.
# For this control, clicks which are not direct hits will slide both
# slider parts
if button:
opt = QtWidgets.QStyleOptionSlider()
self.initStyleOption(opt)
self.active_slider = 0
mid = (self.maximum() - self.minimum()) / 2.0
for i, value in enumerate([self._low, self._high]):
opt.sliderPosition = value
hit = style.hitTestComplexControl(style.CC_Slider, opt, event.pos(), self)
if hit == style.SC_SliderHandle:
self.pressed_control = hit
# if both handles are close together, avoid locks
# choosing the one with more empty space near it
if self._low + 2 >= self._high:
self.active_slider = 1 if self._high < mid else -1
else:
self.active_slider = -1 if i == 0 else 1
self.triggerAction(self.SliderMove)
self.setRepeatAction(self.SliderNoAction)
self.setSliderDown(True)
break
if self.active_slider == 0:
self.pressed_control = QtWidgets.QStyle.SC_SliderHandle
self.click_offset = self.__pixelPosToRangeValue(self.__pick(event.pos()))
self.triggerAction(self.SliderMove)
self.setRepeatAction(self.SliderNoAction)
self.setSliderDown(True)
else:
event.ignore()
[docs] def mouseReleaseEvent(self, event):
if self.pressed_control != QtWidgets.QStyle.SC_SliderHandle:
event.ignore()
return
self.setSliderDown(False)
return QtWidgets.QSlider.mouseReleaseEvent(self, event)
[docs] def mouseMoveEvent(self, event):
if self.pressed_control != QtWidgets.QStyle.SC_SliderHandle:
event.ignore()
return
event.accept()
new_pos = self.__pixelPosToRangeValue(self.__pick(event.pos()))
opt = QtWidgets.QStyleOptionSlider()
self.initStyleOption(opt)
old_click_offset = self.click_offset
self.click_offset = new_pos
if self.active_slider == 0:
offset = new_pos - old_click_offset
new_low = self._low + offset
new_high = self._high + offset
if new_low < self.minimum():
diff = self.minimum() - new_low
new_low += diff
new_high += diff
if new_high > self.maximum():
diff = self.maximum() - new_high
new_low += diff
new_high += diff
self.setLowValue( new_low )
self.setHighValue( new_high )
elif self.active_slider < 0:
if new_pos > self._high:
new_pos = self._high
self.setLowValue( new_pos )
else:
if new_pos < self._low:
new_pos = self._low
self.setHighValue( new_pos )
def __pick(self, pt):
if self.orientation() == QtCore.Qt.Horizontal:
return pt.x()
else:
return pt.y()
def __pixelPosToRangeValue(self, pos):
opt = QtWidgets.QStyleOptionSlider()
self.initStyleOption(opt)
style = QtWidgets.QApplication.style()
gr = style.subControlRect(style.CC_Slider, opt, style.SC_SliderGroove, self)
sr = style.subControlRect(style.CC_Slider, opt, style.SC_SliderHandle, self)
if self.orientation() == QtCore.Qt.Horizontal:
handle_length = sr.width()
slider_min = gr.x() + handle_length/2
slider_max = gr.right() - handle_length/2 + 1
else:
handle_length = sr.height()
slider_min = gr.y() + handle_length/2
slider_max = gr.bottom() - handle_length/2 + 1
return self.minimum() + style.sliderValueFromPosition(0, self.maximum()-self.minimum(),
int(pos-slider_min), int(slider_max - slider_min),
opt.upsideDown)