pythonpyqtpyqt5qlineedit
QlineEdit and signal & slot
I have created a widget with QLineEdit and QLabel, I want to get input from QlineEdit and display it with QLabel. I have used Signal and Slot connection, I do not know what I do wrong, but it is not working correctly. I would like to get both values from QLineEdit and later show it.
Current window
what I want?
Code:
import os
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class WinDialog(QtWidgets.QDialog):
currenttextedited = QtCore.pyqtSignal(int)
def __init__(self, parent=None):
super(WinDialog, self).__init__(parent)
self.setGeometry(300,300,350,300)
self.setWindowTitle("Signal & Slot")
self.propertyWidget = PropertyWidget()
section_lay = QtWidgets.QHBoxLayout()
section_label = QtWidgets.QLabel("Name: ")
section_edit = QtWidgets.QLineEdit('')
length_lay = QtWidgets.QHBoxLayout()
length_label = QtWidgets.QLabel("Input a number: L = ")
self.length_edit = QtWidgets.QLineEdit('1000')
self.length_edit.setInputMask("999999")
self.length_edit.setFocus(True)
thick_lay = QtWidgets.QHBoxLayout()
thick_label = QtWidgets.QLabel("Input a text: T = ")
thick_edit = QtWidgets.QLineEdit('')
section_lay.addWidget(section_label)
section_lay.addWidget(section_edit)
length_lay.addWidget(length_label)
length_lay.addWidget(self.length_edit)
length_lay.addStretch()
thick_lay.addWidget(thick_label)
thick_lay.addWidget(thick_edit)
thick_lay.addStretch()
VB_lay = QtWidgets.QVBoxLayout()
VB_lay.addStretch()
VB_lay.addLayout(length_lay)
VB_lay.addLayout(thick_lay)
VB_lay.addStretch()
buttonBox = QtWidgets.QDialogButtonBox()
buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel
|QtWidgets.QDialogButtonBox.Ok)
buttonBox.accepted.connect(self.accept)
buttonBox.rejected.connect(self.reject)
grid = QtWidgets.QGridLayout(self)
grid.addLayout(section_lay, 0, 0, 1, 2)
grid.addLayout(VB_lay, 1, 0)
grid.addWidget(self.propertyWidget, 2, 0)
grid.addWidget(buttonBox, 3, 0, 1, 2)
self.length_edit.textEdited.connect(self.textchanged)
def textchanged(self, text):
print(text)
self.currenttextedited.emit(text)
class PropertyWidget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(PropertyWidget, self).__init__(parent)
HB_lay = QtWidgets.QHBoxLayout(self)
self.Displaylabel = QtWidgets.QLabel('')
HB_lay.addWidget(self.Displaylabel)
HB_lay.addStretch()
@QtCore.pyqtSlot(int)
def Display(self, text):
try:
L_Display = int(text)
T_Display = int(text)
fmt = "L = {}mm\nT = {}mm"
self.Displaylabel.setText(fmt.format(L_Display, T_Display))
except ValueError:
print("Error")
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = WinDialog()
w.show()
sys.exit(app.exec_())
Solution
according to samples in the image you want to show different texts but you are converting the same number to whole: L_Display = int(text) and T_Display = int(text) so how do you expect to show 2 different texts?, obviously the function display needs 2 entries (2 different entries to self plus I have changed to lowercase since it is recommended that the functions have a lowercase name).
Now the logic is as follows: if any of the texts of length_edit or thick_edit changes then you must call display() passing the new texts. So the solution is to use a slot that connects to the textEdited signals of both QLineEdits and in it obtain the text and pass the texts.
Finally I see that you want the QLineEdits receive only numbers so one option is to use a QIntValidator so that only numbers are acceptable (another better option is to use QSpinBox instead of QLineEdit)
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class WinDialog(QtWidgets.QDialog):
def __init__(self, parent=None):
super(WinDialog, self).__init__(parent)
self.setGeometry(300,300,350,300)
self.setWindowTitle("Signal & Slot")
self.propertyWidget = PropertyWidget()
section_lay = QtWidgets.QHBoxLayout()
section_label = QtWidgets.QLabel("Name: ")
section_edit = QtWidgets.QLineEdit('')
length_lay = QtWidgets.QHBoxLayout()
length_label = QtWidgets.QLabel("Input a number: L = ")
self.length_edit = QtWidgets.QLineEdit()
self.length_edit.setFocus(True)
val_lenght = QtGui.QIntValidator(0, 100000, self.length_edit)
self.length_edit.setValidator(val_lenght)
thick_lay = QtWidgets.QHBoxLayout()
thick_label = QtWidgets.QLabel("Input a text: T = ")
self.thick_edit = QtWidgets.QLineEdit()
val_thick = QtGui.QIntValidator(0, 100000, self.thick_edit)
self.thick_edit.setValidator(val_thick)
section_lay.addWidget(section_label)
section_lay.addWidget(section_edit)
length_lay.addWidget(length_label)
length_lay.addWidget(self.length_edit)
length_lay.addStretch()
thick_lay.addWidget(thick_label)
thick_lay.addWidget(self.thick_edit)
thick_lay.addStretch()
VB_lay = QtWidgets.QVBoxLayout()
VB_lay.addStretch()
VB_lay.addLayout(length_lay)
VB_lay.addLayout(thick_lay)
VB_lay.addStretch()
buttonBox = QtWidgets.QDialogButtonBox()
buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel
| QtWidgets.QDialogButtonBox.Ok)
buttonBox.accepted.connect(self.accept)
buttonBox.rejected.connect(self.reject)
grid = QtWidgets.QGridLayout(self)
grid.addLayout(section_lay, 0, 0, 1, 2)
grid.addLayout(VB_lay, 1, 0)
grid.addWidget(self.propertyWidget, 2, 0)
grid.addWidget(buttonBox, 3, 0, 1, 2)
self.length_edit.textEdited.connect(self.onTextEdited)
self.thick_edit.textEdited.connect(self.onTextEdited)
def onTextEdited(self):
l = self.length_edit.text()
t = self.thick_edit.text()
self.propertyWidget.display(l, t)
class PropertyWidget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(PropertyWidget, self).__init__(parent)
HB_lay = QtWidgets.QHBoxLayout(self)
self.Displaylabel = QtWidgets.QLabel('')
HB_lay.addWidget(self.Displaylabel)
HB_lay.addStretch()
def display(self, l, t):
try:
L_Display = int(l)
T_Display = int(t)
fmt = "L = {}mm\nT = {}mm"
self.Displaylabel.setText(fmt.format(L_Display, T_Display))
except ValueError:
self.Displaylabel.clear()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = WinDialog()
w.show()
sys.exit(app.exec_())