Placing label next to a slider handle

Question

I want a label near the slider's handle, that displays the current value. I used the code provided on the forum and tried to adapt it to Python

from PyQt5 import QtCore, QtGui, QtWidgets

class test(QtWidgets.QWidget):

    def __init__(self, parent = None):
        super().__init__(parent)
        self.main_layout = QtWidgets.QHBoxLayout(self)
        self.main_layout.setContentsMargins(0, 0, 0, 0)
        self.main_layout.setSpacing(0)
        self.slider = QtWidgets.QSlider(QtCore.Qt.Vertical,self)
        self.slider.setMaximum(100)
        self.slider.setMinimum(0)
        self.slider.setTracking(True)
        self.label= QtWidgets.QLabel(self)
        self.label.setText("label")
        self.main_layout.addWidget(self.slider,0,QtCore.Qt.AlignLeft)
        self.main_layout.addWidget(self.label,0,QtCore.Qt.AlignBottom)
        self.updateLabel(0)
        self.setLayout(self.main_layout)
        self.slider.valueChanged.connect(self.updateLabel)


    def updateLabel(self,value):
        height= QtWidgets.QStyle.sliderPositionFromValue(0,100,self.slider.value(),self.slider.height()-self.label.height(), True)
        self.label.move(self.slider.width(), height)
        self.label.setText(str(value))


    def resizeEvent(self,ev):

        self.updateLabel(self.slider.sliderPosition())


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    ui = test()
    ui.show()
    sys.exit(app.exec_())

As a result, I get a label with value, but it is always shown at the bottom of the window.

Once I resize my window, the label moves to the correct place.

Do I miss something?

Answer 1

With the help of @ekhumoro and @simon, I fixed the problem

from PyQt5 import QtCore, QtGui, QtWidgets

class test(QtWidgets.QWidget):

    def __init__(self, parent = None):
        super().__init__(parent)
        self.main_layout = QtWidgets.QHBoxLayout(self)
        self.main_layout.setContentsMargins(0, 0, 0, 0)
        self.main_layout.setSpacing(0)
        self.slider = QtWidgets.QSlider(QtCore.Qt.Vertical,self)
        self.slider.setMaximum(100)
        self.slider.setMinimum(0)
        self.slider.setTracking(True)
        self.label= QtWidgets.QLabel(self)
        self.label.setText("label")
        self.main_layout.addWidget(self.slider,0,QtCore.Qt.AlignLeft)
        self.updateLabel(0)
        self.setLayout(self.main_layout)
        self.slider.valueChanged.connect(self.updateLabel)


    def updateLabel(self,value):
        height= QtWidgets.QStyle.sliderPositionFromValue(0,100,self.slider.value(),self.slider.height()-self.label.height(), True)
        self.label.move(self.slider.width(), height)
        self.label.setText(str(value))


    def resizeEvent(self,ev):

        self.updateLabel(self.slider.sliderPosition())


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    ui = test()
    ui.show()
    sys.exit(app.exec_())

The main difference is not adding the Qlabel inside of the layout, hence having more direct control over its location. One would need to account for label size while using the widget, since by default it's size shrinks to QSlider size