Develop Reference

Detect Slider move

I want to be able to detect if the slider has moved to a new position and then do some actions in another function called sl. Here is my code:
import sys
from PyQt5 import QtWidgets
from PyQt5.QtCore import Qt
from PyQt5.QtWidgets import QApplication, QLabel, QLineEdit, QScrollBar, QMainWindow, QMenu, QWidget, QGridLayout, \
QMessageBox, QListWidget, QPlainTextEdit, QTableWidget, QTableWidgetItem, QHeaderView
from PyQt5.QtWidgets import QMenuBar, QHBoxLayout, QVBoxLayout, QSlider, QPushButton, QDial, QBoxLayout, QSpacerItem
from PyQt5.QtGui import QFont, QColor, QPixmap, QResizeEvent, QPen
import PyQt5.QtGui as QtGui
import PyQt5.QtCore as QtCore
class ControlWidget(QWidget):
def __init__(self):
QWidget.__init__(self)
self.layout = QVBoxLayout()
self.layout.setContentsMargins(10, 10, 10, 10)
widget3 = QLabel("Manual")
big_font = QFont('Arial')
big_font.setPointSize(15)
widget3.setFont(big_font)
self.layout.addWidget(widget3, stretch=1)
widget2 = ManualWidget()
self.layout.addWidget(widget2, stretch=4)
self.setLayout(self.layout)
class ManualWidget(QWidget):
def __init__(self):
QWidget.__init__(self)
self.layout = QHBoxLayout()
right_widget = QWidget()
right_layout = QVBoxLayout()
right_top_widget = QWidget()
self.sld1 = self.slider('V1:', 0, 100)
right_top_layout = QVBoxLayout()
right_top_layout.setContentsMargins(0, 0, 0, 0)
right_top_layout.addWidget(self.sld1, stretch=1)
right_top_widget.setLayout(right_top_layout)
right_layout.addWidget(right_top_widget)
right_widget.setLayout(right_layout)
self.layout.addWidget(right_widget, stretch=1)
self.setLayout(self.layout)
self.layout.addWidget(self.name)
self.layout.addWidget(self.label)
self.layout.addWidget(self.slider)
print(self.sl())
def slider(self, name, low, high, step=10):
self.name = QLabel(str(name))
self.label = QLabel(str(low))
self.slider = QSlider(Qt.Horizontal, self)
self.slider.setMinimum(low)
self.slider.setMaximum(high*step)
self.slider.setValue(low)
self.slider.valueChanged.connect(self.change_value)
self.action = False
self.slider.sliderMoved.connect(self.act1)
def change_value(self):
self.set_point = (float(self.slider.value())) / 10
self.label.setText(str(self.set_point))
def act1(self):
self.action = True
return self.action
def sl(self):
if self.action == True:
x = 3
else:
x = 6
return x
class MainWidget(QWidget):
def __init__(self):
QWidget.__init__(self)
self.layout = QVBoxLayout()
self.layout.setContentsMargins(0, 0, 0, 0)
big_font = QFont('Arial')
big_font.setPointSize(10)
bottom_widget = ControlWidget()
self.layout.addWidget(bottom_widget, stretch=10)
self.setLayout(self.layout)
class Window(QMainWindow):
def __init__(self, widget):
QMainWindow.__init__(self)
self.setWindowTitle("Flow test rig")
self.menu = self.menuBar()
self.setCentralWidget(widget)
self.status = self.statusBar()
widget.parent = self
app = QApplication(sys.argv)
main_widget = MainWidget()
win = Window(main_widget)
win.show()
sys.exit(app.exec_())
I tried to detect it with the act1 function, however, self.action is always False, or when it becomes True, it does not reset to False after the first move of the slider. I appreciate it if someone would help me.

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

PyQt5 - QSlider in real time

I'm creating a software to read and process videos. I just began this project but I already have an issue. I want to create a slider which reacts in real time. Currently, the slider only moves around very seconds.
My slider is set up like that.
self.slider = QSlider(Qt.Horizontal)
self.slider.sliderMoved.connect(self.set_position)
def set_position(self, position):
self.mediaPlayer.setPosition(position)
I tried to use setTickPosition(QSlider::TickPosition position) but it doesn't change anything. Maybe I'm not using the good function.
Maybe this code could help you to see where I stuck
from PyQt5.QtWidgets import QWidget, QApplication, QSlider, QHBoxLayout, QStyle, QFileDialog, QPushButton, QVBoxLayout
from PyQt5.QtMultimedia import QMediaPlayer, QMediaContent
from PyQt5.QtGui import QIcon
from PyQt5.QtMultimediaWidgets import QVideoWidget
from PyQt5.QtCore import Qt, QUrl
import sys
class Window(QWidget):
def __init__(self):
super().__init__()
self.setWindowTitle("Slider tick settings")
self.setGeometry(350, 100, 720, 700)
self.setWindowIcon(QIcon("icon.png"))
self.init_ui()
self.show()
def init_ui(self):
self.mediaPlayer = QMediaPlayer(None, QMediaPlayer.VideoSurface)
VideoWidget = QVideoWidget()
self.slider = QSlider(Qt.Horizontal)
self.slider.sliderMoved.connect(self.set_position)
self.playBtn = QPushButton("Play")
self.openFile = QPushButton("Open File")
self.playBtn.clicked.connect(self.play_video)
self.openFile.clicked.connect(self.open_file)
self.qhbox = QHBoxLayout()
self.qvbox = QVBoxLayout()
self.qhbox.addWidget(self.slider)
self.qhbox.addWidget(self.openFile)
self.qhbox.addWidget(self.playBtn)
self.qvbox.addLayout(self.qhbox)
self.qvbox.addWidget(VideoWidget)
self.setLayout(self.qvbox)
self.mediaPlayer.setVideoOutput(VideoWidget)
self.mediaPlayer.stateChanged.connect(self.mediastate_changed)
self.mediaPlayer.positionChanged.connect(self.position_changed)
self.mediaPlayer.durationChanged.connect(self.duration_changed)
def set_position(self, position):
self.mediaPlayer.setPosition(position)
def mediastate_changed(self, state):
if self.mediaPlayer.state() == QMediaPlayer.PlayingState:
self.playBtn.setIcon(self.style().standardIcon(QStyle.SP_MediaPause))
else:
self.playBtn.setIcon(self.style().standardIcon(QStyle.SP_MediaPlay))
def open_file(self):
filename, _ = QFileDialog.getOpenFileName(self, "Open Video")
if filename != '':
self.mediaPlayer.setMedia(QMediaContent(QUrl.fromLocalFile(filename)))
self.playBtn.setEnabled(True)
#self.getRealFilename(filename)
def position_changed(self, position):
self.slider.setValue(position)
def duration_changed(self, duration):
self.slider.setRange(0, duration)
def set_position(self, position):
self.mediaPlayer.setPosition(position)
def play_video(self):
if self.mediaPlayer.state() == QMediaPlayer.PlayingState :
self.mediaPlayer.pause()
else :
self.mediaPlayer.play()
if __name__ == "__main__":
app = QApplication(sys.argv)
Window = Window()
sys.exit(app.exec_())

Ticks have nothing to do with that, nor the slider.
The problem is the default interval that QMediaPlayer uses for notifications, which is 1000ms.
If you want to change that, use setNotifyInterval() with a proper millisecond interval (I suggest to not use values smaller than 100-150ms).

Python, looking to move text from left to right

This code moves the text from left to right using PyQt4. My question is, are there other ways to do it?
# -*-coding:utf8 -*-
from PyQt4.QtGui import (QApplication, QGraphicsView, QPainter, QColor, QWidget,
QGraphicsScene, QFont, QLabel, QGraphicsSimpleTextItem,
QBrush, QLinearGradient, QPixmap, QGraphicsTextItem, QPushButton,
QVBoxLayout, QTextDocument)
from PyQt4.QtCore import (QObject, QPointF, QPropertyAnimation,
pyqtProperty, Qt, QAbstractAnimation, QRectF)
import sys
data = [u"I want to make text within an ad bar that moves as there is on the TV screen like this"]
class Text(QObject):
def __init__(self):
super(Text, self).__init__()
doc = QTextDocument("%s" % data[0])
doc.setDefaultStyleSheet(
"body { color : green; background-color : black }")
doc.setDefaultFont(QFont("Times", 20, QFont.Bold))
self.Text_item = QGraphicsTextItem()
self.Text_item.setDocument(doc)
def _set_pos(self, pos):
self.Text_item.setPos(pos)
pos = pyqtProperty(QPointF, fset=_set_pos)
class Example(QGraphicsView):
def __init__(self):
super(Example, self).__init__()
self.initView()
def initView(self):
self.text = Text()
self.anim = QPropertyAnimation(self.text, b"pos")
self.anim.setDuration(19000)
self.anim.setLoopCount(4)
self.anim.setStartValue(QPointF(-1850.0, 450.0))
self.anim.setEndValue(QPointF(800.0, 450.0))
self.scene = QGraphicsScene(self)
self.scene.setSceneRect(0, 0, 300, 300)
self.scene.addItem(self.text.Text_item)
self.setScene(self.scene)
self.setWindowTitle("Text moveing")
self.setRenderHint(QPainter.Antialiasing)
self.anim.start(QAbstractAnimation.DeleteWhenStopped)
if __name__ == '__main__':
app = QApplication(sys.argv)
view = Example()
rect = QApplication.desktop().availableGeometry()
view.resize(int(rect.width() * 0.75), int(rect.height() * 0.9))
view.show()
sys.exit(app.exec_())

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_())