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PyQt5 drawing lines that have mouse events

I have an application where I draw 2 custom widgets and then draw a line between them. I want to add a mousePressEvent to the line.
What would be the best way to do this?
I suppose I could create a QWidget of x pixel thickness and y length and then fill in the whole widget with the colour I want the line to have. Then the QWidget has the mousePressEvent that I can override. This doesn't seem like the most elegant solution and feels more like a workaround. Is there a better way?
import sys
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPaintEvent, QPainter, QPen, QFont
from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QLabel
class MyWidget(QWidget):
def __init__(self, name, parent):
super().__init__(parent)
self.setAutoFillBackground(True)
self.setFixedSize(300, 100)
p = self.palette()
p.setColor(self.backgroundRole(), Qt.white)
self.setPalette(p)
lbl_name = QLabel(name, self)
lbl_name.setFont(QFont('Arial', 16))
lbl_name.move((self.width() - lbl_name.width()) / 2, self.height()/2 - lbl_name.height()/2)
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super().__init__(parent)
self.main_widget = QWidget(self)
self.widget_1 = MyWidget("Widget 1", self)
self.widget_1.move(50, 50)
self.widget_2 = MyWidget("Widget 2", self)
self.widget_2.move(700, 600)
self.resize(1200, 800)
self.setCentralWidget(self.main_widget)
def paintEvent(self, a0: QPaintEvent) -> None:
super().paintEvent(a0)
painter = QPainter(self)
painter.setPen(QPen(Qt.red, 3, Qt.SolidLine))
widget_1_x = self.widget_1.pos().x() + self.widget_1.size().width()
widget_1_y = self.widget_1.pos().y() + self.widget_1.size().height() / 2
widget_2_x = self.widget_2.pos().x()
widget_2_y = self.widget_2.pos().y() + self.widget_2.size().height() / 2
halfway_x = widget_1_x + (widget_2_x - widget_1_x) / 2
# add mousePressEvents to these lines:
painter.drawLine(widget_1_x, widget_1_y, halfway_x, widget_1_y)
painter.drawLine(halfway_x, widget_1_y, halfway_x, widget_2_y)
painter.drawLine(halfway_x, widget_2_y, widget_2_x, widget_2_y)
if __name__ == "__main__":
app = QApplication(sys.argv)
myapp = MainWindow()
myapp.show()
sys.exit(app.exec_())
How the above code looks like when run

error when close with effect fade window pyqt5

I have a bit when try change new window UI with effect fade. I added effect on closeEvent of mainwindow but it doen't work.
This is my code:
library used:
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5 import uic
load ui
uifile_1 = 'home.ui'
form_1, base_1 = uic.loadUiType(uifile_1)
uifile_2 = 'plate.ui'
form_2, base_2 = uic.loadUiType(uifile_2)
Class Home page:
class HomePage(base_1, form_1):
def __init__(self):
super(base_1,self).__init__()
self.setupUi(self)
#add button for click next page
self.btn_start = QPushButton(self)
self.btn_start.clicked.connect(self.change)
self._heightMask = self.height()
self.animation = QPropertyAnimation(self, b"heightPercentage")
self.animation.setDuration(1000)
self.animation.setStartValue(self.height())
self.animation.setEndValue(-1)
self.animation.finished.connect(self.close)
self.isStarted = False
def change(self):
self.plate = PlatePage()
self.plate.show()
self.close()
#pyqtProperty(int)
def heightMask(self):
return self._heightMask
#heightMask.setter
def heightPercentage(self, value):
self._heightMask = value
rect = QRect(0, 0, self.width(), self.heightMask)
self.setMask(QRegion(rect))
def closeEvent(self, event):
if not self.isStarted:
self.animation.start()
self.isStarted = True
event.ignore()
else:
self.closeEvent(self, event)
Class Plate Page
class PlatePage(base_2, form_2):
def __init__(self):
super(base_2, self).__init__()
self.setupUi(self)
self.show()
Please have a look and give me some solution.
Thank You

Try it:
from PyQt5.QtCore import QPropertyAnimation, QThread
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QPushButton
class Window(QWidget):
def __init__(self, *args, **kwargs):
super(Window, self).__init__(*args, **kwargs)
self.resize(400, 400)
layout = QVBoxLayout(self)
layout.addWidget(QPushButton('Button', self))
self.animation = QPropertyAnimation(self, b'windowOpacity')
self.animation.setDuration(1000)
self.isStarted = False
self.doShow()
def doShow(self):
try:
self.animation.finished.disconnect(self.close)
except:
pass
self.animation.stop()
self.animation.setStartValue(0)
self.animation.setEndValue(1)
self.animation.start()
def closeEvent(self, event):
if not self.isStarted:
self.animation.stop()
self.animation.finished.connect(self.close)
self.animation.setStartValue(1)
self.animation.setEndValue(0)
self.animation.start()
self.isStarted = True
event.ignore()
else:
event.accept()
if __name__ == '__main__':
import sys
from PyQt5.QtWidgets import QApplication
app = QApplication(sys.argv)
w = Window()
w.show()
sys.exit(app.exec_())

How to add a pixmap drawn in QGraphicsItem to QGraphicsScene? [duplicate]

This question already exists:
How to make the picture zoom (QGraphicsItem), and make scrollbars change their size accordingly (QGraphicsScene)? [duplicate]
Closed 4 years ago.
How to add a pixmap drawn in QGraphicsItem to QGraphicsScene in the following example?
#!/usr/bin/env python
from PyQt5.QtCore import QRectF, Qt
from PyQt5.QtGui import QPixmap
from PyQt5.QtWidgets import QApplication, QGraphicsItem, QGraphicsView, QGraphicsScene, QMainWindow
class TicTacToe(QGraphicsItem):
def __init__(self, helper):
super(TicTacToe, self).__init__()
self.mypixmap = QPixmap("exit.png")
def paint(self, painter, option, widget):
painter.setOpacity(1)
painter.drawPixmap(0,0, 300, 300, self.mypixmap)
def boundingRect(self):
return QRectF(0,0,300,300)
class MyGraphicsView(QGraphicsView):
def __init__(self):
super(MyGraphicsView, self).__init__()
scene = QGraphicsScene(self)
self.tic_tac_toe = TicTacToe(self)
scene.addItem(self.tic_tac_toe)
self.setScene(scene)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
class Example(QMainWindow):
def __init__(self):
super(Example, self).__init__()
self.y = MyGraphicsView()
self.setCentralWidget(self.y)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
w = Example()
w.show()
sys.exit(app.exec_())

Try it:
Drag and drop image,
Enlarge Image -> Qt.Key_Right,
Reduce image <- Qt.Key_Left.
from PyQt5.QtCore import (QLineF, QPointF, QRectF,
pyqtSignal, QStandardPaths, Qt)
from PyQt5.QtGui import (QIcon, QBrush, QColor, QPainter, QPixmap)
from PyQt5.QtWidgets import (QAction, QMainWindow, QApplication,
QGraphicsObject,
QGraphicsView, QGraphicsScene, QGraphicsItem,
QGridLayout, QVBoxLayout, QHBoxLayout,
QFileDialog, QLabel, QLineEdit, QPushButton)
from PyQt5.QtOpenGL import QGLFormat
class MyGraphicsView(QGraphicsView):
backgroundColor = QColor(28, 31, 34) # Background color
def __init__(self):
super(MyGraphicsView, self).__init__()
self.resize(800, 600)
self.setBackgroundBrush(self.backgroundColor)
self.setCacheMode(self.CacheBackground)
self.setRenderHints(
QPainter.Antialiasing | QPainter.TextAntialiasing | QPainter.SmoothPixmapTransform)
if QGLFormat.hasOpenGL():
self.setRenderHint(QPainter.HighQualityAntialiasing)
self.setViewportUpdateMode(self.SmartViewportUpdate)
self._scene = QGraphicsScene(-400, -300, 800, 600, self)
self.setScene(self._scene)
self._itemImage = None
def keyReleaseEvent(self, event):
""" Button processing event """
self._scaleImage(event)
super(MyGraphicsView, self).keyReleaseEvent(event)
def closeEvent(self, event):
""" Clear all items in the scene when the window is `closed` """
self._scene.clear()
self._itemImage = None
super(MyGraphicsView, self).closeEvent(event)
def _scaleImage(self, event):
""" Image zoom operation """
if not self._itemImage:
return
scale = self._itemImage.scale()
if event.key() == Qt.Key_Right:
# Enlarge Image -> Qt.Key_Right
if scale >= 0.91:
return
self._itemImage.setScale(scale + 0.1)
elif event.key() == Qt.Key_Left:
# Reduce image <- Qt.Key_Left
if scale <= 0.11:
return
self._itemImage.setScale(scale - 0.1)
def loadImage(self):
path, _ = QFileDialog.getOpenFileName(
self, 'Please select an image',
QStandardPaths.writableLocation(QStandardPaths.DesktopLocation),
'Image(*.jpg *.png)')
if not path:
return
if self._itemImage:
# Delete previous item
self._scene.removeItem(self._itemImage)
del self._itemImage
self._itemImage = self._scene.addPixmap(QPixmap(path))
self._itemImage.setFlag(QGraphicsItem.ItemIsMovable)
self._itemImage.setScale(0.1) # Default load factor
size = self._itemImage.pixmap().size()
# Adjust the image in the middle
self._itemImage.setPos(
-size.width() * self._itemImage.scale() / 2,
-size.height() * self._itemImage.scale() / 2
)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
w = MyGraphicsView()
w.show()
ww = QPushButton('Select a file', clicked=w.loadImage)
ww.show()
sys.exit(app.exec_())

Draw QFrame around QPushButton PyQt5

I am unable to get a QFrame to completely surround a QPushButton Like a Border. It only frames the top and left side of the button. I was wondering what I'm doing wrong with the frame.
import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
class main(QWidget):
def __init__(self):
super().__init__()
layout1 = QVBoxLayout()
btn1 = QPushButton("Test")
frame = QFrame(btn1)
frame.setGeometry(btn1.geometry())
frame.setFrameShape(QFrame.Box)
frame.setFrameShadow(QFrame.Plain)
frame.setLineWidth(4)
layout1.addWidget(btn1)
self.setLayout(layout1)
if __name__ == '__main__':
app = QApplication(sys.argv)
window = main()
window.show()
sys.exit(app.exec_())

The problem is caused because the QFrame does not change the size, instead QPushButton does. In my solution I have resized every time the size is changed in the QPushButton
class FrameButton(QPushButton):
def __init__(self, *args, **kwargs):
QPushButton.__init__(self, *args, **kwargs)
self.frame = QFrame(self)
self.frame.setFrameShape(QFrame.Box)
self.frame.setFrameShadow(QFrame.Plain)
self.frame.setLineWidth(4)
def resizeEvent(self, event):
self.frame.resize(self.size())
QWidget.resizeEvent(self, event)
class main(QWidget):
def __init__(self):
super().__init__()
layout = QVBoxLayout(self)
layout.addWidget(FrameButton("Test"))

PyQt5: painting using events

I am new on PyQt I am working on a project on which I should implement a feature that make the user able to draw a digit using the mouse (digit recognition system). So what I want is when the mouse button is pressed the app will start to draw till the button is released. I made this source code but it is still not working (I think I am struggling with sending a signal to PaintEvent()).
import sys
from PyQt5 import QtCore
from PyQt5 import QtGui, QtWidgets
from PyQt5.QtWidgets import QApplication, QWidget, QInputDialog, QLineEdit, QFileDialog,QGraphicsView,QGraphicsScene,QVBoxLayout
from PyQt5.QtWidgets import (QApplication, QLabel, QWidget)
from PyQt5.QtGui import QPainter, QColor, QPen
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPainter
from PyQt5.QtCore import pyqtSignal, QObject
from PyQt5.QtWidgets import QMainWindow, QApplication
class Communicate(QObject):
drawApp = pyqtSignal()
class MyWidget(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.setGeometry(300, 300, 300, 220)
self.setWindowTitle('Simple')
self.setMouseTracking(True)
self.label = QLabel(self)
self.label.resize(500, 40)
self.c = Communicate()
self.c.drawApp.connect(self.PaintEvent())
self.show()
def mousePressEvent(self, event):
self.c.drawApp.emit()
self.startingposx = event.x()
self.startingposy = event.y()
#super().mousePressEvent(event)
print ("mouse pressed")
def mouseMoveEvent(self, event):
self.label.setText('Coordinates: ( %d : %d )' % (event.x(), event.y()) )
self.y = event.y()
self.x=event.x()
def PaintEvent(self,event):
qp = QPainter()
qp.begin(self)
#qp.setPen(Qt.red)
qp.drawPoints(self,qp)
qp.end()
self.update()
def mouseReleaseEvent(self,event):
self.endingposx = event.x()
self.endingposy = event.y()
super().mouseReleaseEvent(event)
print("starting point was",self.startingposx)
print("starting point y was ",self.startingposy)
print("ending point was ",self.endingposx)
print("ending point was y ",self.endingposy)
print("released")
def drawPoints(self,qp):
qp.setPen(Qt.red)
size = self.size()
x=self.x
y=self.y
qp.drawPoint(x,y)
app = QApplication(sys.argv)
widget = MyWidget()
widget.show()
app.exec_()

Python is sensitive to uppercase and lowercase so be more careful, the method is called paintEvent.
Also you should not call paintEvent directly, you must use the function update(), this method will internally call paintEvent().
But even correcting that error your problem is not solved, if you want to draw a path it is advisable to use QPainterPath as this stores the strokes.
class Drawer(QWidget):
newPoint = pyqtSignal(QPoint)
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.path = QPainterPath()
def paintEvent(self, event):
painter = QPainter(self)
painter.drawPath(self.path)
def mousePressEvent(self, event):
self.path.moveTo(event.pos())
self.update()
def mouseMoveEvent(self, event):
self.path.lineTo(event.pos())
self.newPoint.emit(event.pos())
self.update()
def sizeHint(self):
return QSize(400, 400)
class MyWidget(QWidget):
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.setLayout(QVBoxLayout())
label = QLabel(self)
drawer = Drawer(self)
drawer.newPoint.connect(lambda p: label.setText('Coordinates: ( %d : %d )' % (p.x(), p.y())))
self.layout().addWidget(label)
self.layout().addWidget(drawer)
if __name__ == '__main__':
app = QApplication(sys.argv)
w = MyWidget()
w.show()
sys.exit(app.exec_())
Screenshot:

I don't have the reputation to reply to eyllanesc's solution, but in case others are having issues, the imports were not complete. Here's is eyllanesc's solution with the imports. It will execute without error:
import sys
from PyQt5.QtWidgets import QVBoxLayout
from PyQt5.QtWidgets import (QLabel, QWidget)
from PyQt5.QtGui import QPainter, QPainterPath
from PyQt5.QtCore import pyqtSignal, QPoint, QSize
from PyQt5.QtWidgets import QApplication
class Drawer(QWidget):
newPoint = pyqtSignal(QPoint)
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.path = QPainterPath()
def paintEvent(self, event):
painter = QPainter(self)
painter.drawPath(self.path)
def mousePressEvent(self, event):
self.path.moveTo(event.pos())
self.update()
def mouseMoveEvent(self, event):
self.path.lineTo(event.pos())
self.newPoint.emit(event.pos())
self.update()
def sizeHint(self):
return QSize(400, 400)
class MyWidget(QWidget):
def __init__(self, parent=None):
QWidget.__init__(self, parent)
self.setLayout(QVBoxLayout())
label = QLabel(self)
drawer = Drawer(self)
drawer.newPoint.connect(lambda p: label.setText('Coordinates: ( %d : %d )' % (p.x(), p.y())))
self.layout().addWidget(label)
self.layout().addWidget(drawer)
if __name__ == '__main__':
app = QApplication(sys.argv)
w = MyWidget()
w.show()
sys.exit(app.exec_())