Article Outline
Python pyqt (gui) example 'moveblocks'
Functions in program:
def createGeometryState(w1, rect1, w2, rect2, w3, rect3, w4, rect4, parent):
moveblocks
Python pyqt example: moveblocks
#!/usr/bin/env python
#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
## All rights reserved.
##
## This file is part of the examples of PyQt.
##
## $QT_BEGIN_LICENSE:BSD$
## You may use this file under the terms of the BSD license as follows:
##
## "Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are
## met:
## * Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
## * Redistributions in binary form must reproduce the above copyright
## notice, this list of conditions and the following disclaimer in
## the documentation and/or other materials provided with the
## distribution.
## * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
## the names of its contributors may be used to endorse or promote
## products derived from this software without specific prior written
## permission.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
## $QT_END_LICENSE$
##
#############################################################################
from PyQt5.QtCore import (QAbstractTransition, QEasingCurve, QEvent,
QParallelAnimationGroup, QPropertyAnimation, qrand, QRect,
QSequentialAnimationGroup, qsrand, QState, QStateMachine, Qt, QTime,
QTimer)
from PyQt5.QtWidgets import (QApplication, QGraphicsScene, QGraphicsView,
QGraphicsWidget)
class StateSwitchEvent(QEvent):
StateSwitchType = QEvent.User + 256
def __init__(self, rand=0):
super(StateSwitchEvent, self).__init__(StateSwitchEvent.StateSwitchType)
self.m_rand = rand
def rand(self):
return self.m_rand
class QGraphicsRectWidget(QGraphicsWidget):
def paint(self, painter, option, widget):
painter.fillRect(self.rect(), Qt.blue)
class StateSwitchTransition(QAbstractTransition):
def __init__(self, rand):
super(StateSwitchTransition, self).__init__()
self.m_rand = rand
def eventTest(self, event):
return (event.type() == StateSwitchEvent.StateSwitchType and
event.rand() == self.m_rand)
def onTransition(self, event):
pass
class StateSwitcher(QState):
def __init__(self, machine):
super(StateSwitcher, self).__init__(machine)
self.m_stateCount = 0
self.m_lastIndex = 0
def onEntry(self, event):
n = qrand() % self.m_stateCount + 1
while n == self.m_lastIndex:
n = qrand() % self.m_stateCount + 1
self.m_lastIndex = n
self.machine().postEvent(StateSwitchEvent(n))
def onExit(self, event):
pass
def addState(self, state, animation):
self.m_stateCount += 1
trans = StateSwitchTransition(self.m_stateCount)
trans.setTargetState(state)
self.addTransition(trans)
trans.addAnimation(animation)
def createGeometryState(w1, rect1, w2, rect2, w3, rect3, w4, rect4, parent):
result = QState(parent)
result.assignProperty(w1, 'geometry', rect1)
result.assignProperty(w1, 'geometry', rect1)
result.assignProperty(w2, 'geometry', rect2)
result.assignProperty(w3, 'geometry', rect3)
result.assignProperty(w4, 'geometry', rect4)
return result
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
button1 = QGraphicsRectWidget()
button2 = QGraphicsRectWidget()
button3 = QGraphicsRectWidget()
button4 = QGraphicsRectWidget()
button2.setZValue(1)
button3.setZValue(2)
button4.setZValue(3)
scene = QGraphicsScene(0, 0, 300, 300)
scene.setBackgroundBrush(Qt.black)
scene.addItem(button1)
scene.addItem(button2)
scene.addItem(button3)
scene.addItem(button4)
window = QGraphicsView(scene)
window.setFrameStyle(0)
window.setAlignment(Qt.AlignLeft | Qt.AlignTop)
window.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
window.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
machine = QStateMachine()
group = QState()
timer = QTimer()
timer.setInterval(1250)
timer.setSingleShot(True)
group.entered.connect(timer.start)
state1 = createGeometryState(button1, QRect(100, 0, 50, 50), button2,
QRect(150, 0, 50, 50), button3, QRect(200, 0, 50, 50), button4,
QRect(250, 0, 50, 50), group)
state2 = createGeometryState(button1, QRect(250, 100, 50, 50), button2,
QRect(250, 150, 50, 50), button3, QRect(250, 200, 50, 50), button4,
QRect(250, 250, 50, 50), group)
state3 = createGeometryState(button1, QRect(150, 250, 50, 50), button2,
QRect(100, 250, 50, 50), button3, QRect(50, 250, 50, 50), button4,
QRect(0, 250, 50, 50), group)
state4 = createGeometryState(button1, QRect(0, 150, 50, 50), button2,
QRect(0, 100, 50, 50), button3, QRect(0, 50, 50, 50), button4,
QRect(0, 0, 50, 50), group)
state5 = createGeometryState(button1, QRect(100, 100, 50, 50), button2,
QRect(150, 100, 50, 50), button3, QRect(100, 150, 50, 50), button4,
QRect(150, 150, 50, 50), group)
state6 = createGeometryState(button1, QRect(50, 50, 50, 50), button2,
QRect(200, 50, 50, 50), button3, QRect(50, 200, 50, 50), button4,
QRect(200, 200, 50, 50), group)
state7 = createGeometryState(button1, QRect(0, 0, 50, 50), button2,
QRect(250, 0, 50, 50), button3, QRect(0, 250, 50, 50), button4,
QRect(250, 250, 50, 50), group)
group.setInitialState(state1)
animationGroup = QParallelAnimationGroup()
anim = QPropertyAnimation(button4, b'geometry')
anim.setDuration(1000)
anim.setEasingCurve(QEasingCurve.OutElastic)
animationGroup.addAnimation(anim)
subGroup = QSequentialAnimationGroup(animationGroup)
subGroup.addPause(100)
anim = QPropertyAnimation(button3, b'geometry')
anim.setDuration(1000)
anim.setEasingCurve(QEasingCurve.OutElastic)
subGroup.addAnimation(anim)
subGroup = QSequentialAnimationGroup(animationGroup)
subGroup.addPause(150)
anim = QPropertyAnimation(button2, b'geometry')
anim.setDuration(1000)
anim.setEasingCurve(QEasingCurve.OutElastic)
subGroup.addAnimation(anim)
subGroup = QSequentialAnimationGroup(animationGroup)
subGroup.addPause(200)
anim = QPropertyAnimation(button1, b'geometry')
anim.setDuration(1000)
anim.setEasingCurve(QEasingCurve.OutElastic)
subGroup.addAnimation(anim)
stateSwitcher = StateSwitcher(machine)
group.addTransition(timer.timeout, stateSwitcher)
stateSwitcher.addState(state1, animationGroup)
stateSwitcher.addState(state2, animationGroup)
stateSwitcher.addState(state3, animationGroup)
stateSwitcher.addState(state4, animationGroup)
stateSwitcher.addState(state5, animationGroup)
stateSwitcher.addState(state6, animationGroup)
stateSwitcher.addState(state7, animationGroup)
machine.addState(group)
machine.setInitialState(group)
machine.start()
window.resize(300, 300)
window.show()
qsrand(QTime(0, 0, 0).secsTo(QTime.currentTime()))
sys.exit(app.exec_())
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/