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Python pyqt (gui) example 'mainwindow'
mainwindow
Python pyqt example: mainwindow
#############################################################################
##
## Copyright (C) 2015 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.
##
## $QT_BEGIN_LICENSE:LGPL$
## Commercial Usage
## Licensees holding valid Qt Commercial licenses may use this file in
## accordance with the Qt Commercial License Agreement provided with the
## Software or, alternatively, in accordance with the terms contained in
## a written agreement between you and Nokia.
##
## GNU Lesser General Public License Usage
## Alternatively, this file may be used under the terms of the GNU Lesser
## General Public License version 2.1 as published by the Free Software
## Foundation and appearing in the file LICENSE.LGPL included in the
## packaging of this file. Please review the following information to
## ensure the GNU Lesser General Public License version 2.1 requirements
## will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
##
## In addition, as a special exception, Nokia gives you certain additional
## rights. These rights are described in the Nokia Qt LGPL Exception
## version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
##
## GNU General Public License Usage
## Alternatively, this file may be used under the terms of the GNU
## General Public License version 3.0 as published by the Free Software
## Foundation and appearing in the file LICENSE.GPL included in the
## packaging of this file. Please review the following information to
## ensure the GNU General Public License version 3.0 requirements will be
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## $QT_END_LICENSE$
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#############################################################################
from PyQt5.QtCore import QFileInfo, QPoint, QRect, qRound, Qt, QTime, QTimer
from PyQt5.QtGui import (QFontMetricsF, QImage, QPainter, QPixmap, QPolygon,
QRegion)
from PyQt5.QtWidgets import (QApplication, QFrame, QGraphicsScene,
QGraphicsView, QGraphicsWidget, QMessageBox, QWidget)
from colors import Colors
from demoitem import DemoItem
from demotextitem import DemoTextItem
from imageitem import ImageItem
from menumanager import MenuManager
class MainWindow(QGraphicsView):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.imagesDir = QFileInfo(__file__).absolutePath() + '/images'
self.updateTimer = QTimer(self)
self.demoStartTime = QTime()
self.fpsTime = QTime()
self.background = QPixmap()
self.scene = None
self.mainSceneRoot = None
self.frameTimeList = []
self.fpsHistory = []
self.currentFps = Colors.fps
self.fpsMedian = -1
self.fpsLabel = None
self.pausedLabel = None
self.doneAdapt = False
self.useTimer = False
self.updateTimer.setSingleShot(True)
self.companyLogo = None
self.qtLogo = None
self.setupWidget()
self.setupScene()
self.setupSceneItems()
self.drawBackgroundToPixmap()
def setupWidget(self):
desktop = QApplication.desktop()
screenRect = desktop.screenGeometry(desktop.primaryScreen())
windowRect = QRect(0, 0, 800, 600)
if screenRect.width() < 800:
windowRect.setWidth(screenRect.width())
if screenRect.height() < 600:
windowRect.setHeight(screenRect.height())
windowRect.moveCenter(screenRect.center())
self.setGeometry(windowRect)
self.setMinimumSize(80, 60)
self.setWindowTitle("PyQt Examples")
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setFrameStyle(QFrame.NoFrame)
self.setRenderingSystem()
self.updateTimer.timeout.connect(self.tick)
def setRenderingSystem(self):
self.setCacheMode(QGraphicsView.CacheBackground)
self.setViewport(QWidget())
def start(self):
self.switchTimerOnOff(True)
self.demoStartTime.restart()
MenuManager.instance().itemSelected(MenuManager.ROOT,
Colors.rootMenuName)
Colors.debug("- starting demo")
def enableMask(self, enable):
if not enable or Colors.noWindowMask:
self.clearMask()
else:
region = QPolygon([
# North side.
0, 0,
800, 0,
# East side.
# 800, 70,
# 790, 90,
# 790, 480,
# 800, 500,
800, 600,
# South side.
700, 600,
670, 590,
130, 590,
100, 600,
0, 600,
# West side.
# 0, 550,
# 10, 530,
# 10, 520,
# 0, 520,
0, 0])
self.setMask(QRegion(region))
def setupScene(self):
self.scene = QGraphicsScene(self)
self.scene.setSceneRect(0, 0, 800, 600)
self.setScene(self.scene)
self.scene.setItemIndexMethod(QGraphicsScene.NoIndex)
def switchTimerOnOff(self, on):
ticker = MenuManager.instance().ticker
if ticker and ticker.scene():
ticker.tickOnPaint = not on or Colors.noTimerUpdate
if on and not Colors.noTimerUpdate:
self.useTimer = True
self.fpsTime = QTime.currentTime()
self.updateTimer.start(int(1000 / Colors.fps))
update_mode = QGraphicsView.NoViewportUpdate
else:
self.useTimer = False
self.updateTimer.stop()
if Colors.noTicker:
update_mode = QGraphicsView.MinimalViewportUpdate
else:
update_mode = QGraphicsView.SmartViewportUpdate
self.setViewportUpdateMode(update_mode)
def measureFps(self):
# Calculate time difference.
t = self.fpsTime.msecsTo(QTime.currentTime())
if t == 0:
t = 0.01
self.currentFps = (1000.0 / t)
self.fpsHistory.append(self.currentFps)
self.fpsTime = QTime.currentTime()
# Calculate median.
size = len(self.fpsHistory)
if size == 10:
self.fpsHistory.sort()
self.fpsMedian = self.fpsHistory[int(size / 2)]
if self.fpsMedian == 0:
self.fpsMedian = 0.01
self.fpsHistory = []
return True
return False
def forceFpsMedianCalculation(self):
# Used for adaption in case things are so slow that no median has yet
# been calculated.
if self.fpsMedian != -1:
return
size = len(self.fpsHistory)
if size == 0:
self.fpsMedian = 0.01
return
self.fpsHistory.sort()
self.fpsMedian = self.fpsHistory[size // 2]
if self.fpsMedian == 0:
self.fpsMedian = 0.01
def tick(self):
medianChanged = self.measureFps()
self.checkAdapt()
if medianChanged and self.fpsLabel and Colors.showFps:
self.fpsLabel.setText("FPS: %d" % int(self.currentFps))
if MenuManager.instance().ticker:
MenuManager.instance().ticker.tick()
self.viewport().update()
if self.useTimer:
self.updateTimer.start(int(1000 / Colors.fps))
def setupSceneItems(self):
if Colors.showFps:
self.fpsLabel = DemoTextItem("FPS: --", Colors.buttonFont(),
Qt.white, -1, None, DemoTextItem.DYNAMIC_TEXT)
self.fpsLabel.setZValue(1000)
self.fpsLabel.setPos(Colors.stageStartX,
600 - QFontMetricsF(Colors.buttonFont()).height() - 5)
self.mainSceneRoot = QGraphicsWidget()
self.scene.addItem(self.mainSceneRoot)
self.companyLogo = ImageItem(
QImage(self.imagesDir + '/trolltech-logo.png'),
1000, 1000, None, True, 0.5)
self.qtLogo = ImageItem(QImage(self.imagesDir + '/qtlogo_small.png'),
1000, 1000, None, True, 0.5)
self.companyLogo.setZValue(100)
self.qtLogo.setZValue(100)
self.pausedLabel = DemoTextItem("PAUSED", Colors.buttonFont(),
Qt.white, -1, None)
self.pausedLabel.setZValue(100)
fm = QFontMetricsF(Colors.buttonFont())
self.pausedLabel.setPos(Colors.stageWidth - fm.width("PAUSED"),
590 - fm.height())
self.pausedLabel.setRecursiveVisible(False)
def checkAdapt(self):
if self.doneAdapt or Colors.noTimerUpdate or self.demoStartTime.elapsed() < 2000:
return
self.doneAdapt = True
self.forceFpsMedianCalculation()
Colors.benchmarkFps = self.fpsMedian
Colors.debug("- benchmark: %d FPS" % int(Colors.benchmarkFps))
if Colors.noAdapt:
return
if self.fpsMedian < 30:
ticker = MenuManager.instance().ticker
if ticker and ticker.scene():
self.scene.removeItem(ticker)
Colors.noTimerUpdate = True
self.switchTimerOnOff(False)
if self.fpsLabel:
self.fpsLabel.setText("FPS: (%d)" % int(self.fpsMedian))
Colors.debug("- benchmark adaption: removed ticker (fps < 30)")
if self.fpsMedian < 20:
Colors.noAnimations = True
Colors.debug("- benchmark adaption: animations switched off (fps < 20)")
Colors.adapted = True
def drawBackgroundToPixmap(self):
r = self.scene.sceneRect()
self.background = QPixmap(qRound(r.width()), qRound(r.height()))
self.background.fill(Qt.black)
painter = QPainter(self.background)
bg = QImage(self.imagesDir + '/demobg.png')
painter.drawImage(0, 0, bg)
def drawBackground(self, painter, rect):
painter.drawPixmap(QPoint(0, 0), self.background)
def toggleFullscreen(self):
if self.isFullScreen():
self.enableMask(True)
self.showNormal()
if MenuManager.instance().ticker:
MenuManager.instance().ticker.pause(False)
else:
self.enableMask(False)
self.showFullScreen()
def keyPressEvent(self, event):
if event.key() == Qt.Key_Escape:
QApplication.quit()
elif event.key() == Qt.Key_F1:
s = ""
s += "\nAdapt: "
s += ["on", "off"][Colors.noAdapt]
s += "\nAdaption occured: "
s += ["no", "yes"][Colors.adapted]
w = QWidget()
s += "\nColor bit depth: %d" % w.depth()
s += "\nWanted FPS: %d" % Colors.fps
s += "\nBenchmarked FPS: ";
if Colors.benchmarkFps != -1:
s += "%d" % Colors.benchmarkFps
else:
s += "not calculated"
s += "\nAnimations: ";
s += ["on", "off"][Colors.noAnimations]
s += "\nBlending: ";
s += ["on", "off"][Colors.useEightBitPalette]
s += "\nTicker: ";
s += ["on", "off"][Colors.noTicker]
s += "\nPixmaps: ";
s += ["off", "on"][Colors.usePixmaps]
s += "\nRescale images on resize: ";
s += ["on", "off"][Colors.noRescale]
s += "\nTimer based updates: ";
s += ["on", "off"][Colors.noTimerUpdate]
s += "\nSeparate loop: ";
s += ["no", "yes"][Colors.useLoop]
s += "\nScreen sync: ";
s += ["yes", "no"][Colors.noScreenSync]
QMessageBox.information(None, "Current configuration", s)
super(MainWindow, self).keyPressEvent(event)
def focusInEvent(self, event):
if not Colors.pause:
return
if MenuManager.instance().ticker:
MenuManager.instance().ticker.pause(False)
code = MenuManager.instance().currentMenuCode
if code in (MenuManager.ROOT, MenuManager.MENU1):
self.switchTimerOnOff(True)
self.pausedLabel.setRecursiveVisible(False)
def focusOutEvent(self, event):
if not Colors.pause:
return
if MenuManager.instance().ticker:
MenuManager.instance().ticker.pause(True)
code = MenuManager.instance().currentMenuCode
if code in (MenuManager.ROOT, MenuManager.MENU1):
self.switchTimerOnOff(False)
self.pausedLabel.setRecursiveVisible(True)
def resizeEvent(self, event):
self.resetTransform()
self.scale(event.size().width() / 800.0, event.size().height() / 600.0)
super(MainWindow, self).resizeEvent(event)
DemoItem.setTransform(self.transform())
if self.companyLogo:
r = self.scene.sceneRect()
ttb = self.companyLogo.boundingRect()
self.companyLogo.setPos(int((r.width() - ttb.width()) / 2),
595 - ttb.height())
qtb = self.qtLogo.boundingRect()
self.qtLogo.setPos(802 - qtb.width(), 0)
# Changing size will almost always hurt FPS during the change so ignore
# it.
self.fpsHistory = []
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/