Overriding QLabel widget in PyQT - excel

Question

I am new to PyQt perhaps thats why facing this issue. I am trying to make a component inserter for excel sheets. For this purpose I am using QT for interface and using Qlabels within parent class of QMainWindow. On the basis of item selected from Qlist Widget, few Qlabels have to change on mainwindow dynamically Component inserter
As can be seen in above picture, the labels like WCAP-; Part Number and all below needs to change dynamically when the selected items change(when select button is clicked). But what happening is if I choose a different item from list, the previous Label stays and the new label is overlapping it as can be seen from picture below showing overlapping of labels
The code below shows that whenever button "Select" is pressed", label2 (Qlabel2) is formed, how can i delete the previous label whenever select button is pressed so that new Label dynamically replaces the old label.
Thanks a lot in advance.
def Display(self):
self.close()
label1 = QtGui.QLabel("Select the sheet",self)
label1.move(0,15)
self.listwidget = QtGui.QListWidget(self)
self.listwidget.move(0,40)
self.listwidget.resize(150,150)
for i in range(len(self.sheetnames)):
self.listwidget.addItem("%s"%self.sheetnames[i])
btn = QtGui.QPushButton('Select',self)
btn.resize(50,50)
btn.move(170,40)
btn.clicked.connect(self.Selected)
self.show()
def Selected(self):
self.close()
selecteditem = self.listwidget.currentItem().text()
self.sheetindex = self.sheetnames.index(selecteditem)
print self.sheetindex
aa = self.loadsheet.sheet_by_name(selecteditem)
global label2
label2 = QtGui.QLabel("",self)
label2.setText(selecteditem)
label2.move(0,190)
self.show()
self.InputParameters(aa)

Answer 1

You see a new QLabel because you create a new one every time you call Selected. I would initiate the UI at the creation of the widget (in the __init__ method):
def __init__(self):
self.label2 = QtGui.QLabel("",self)
And only update the text of the Qlabel when Selected is executed:
def Selected(self):
self.label2.setText(selecteditem)
About reinitializing all labels with an unknown number of labels and removing the old ones, you might want to look at QLabel.setParent(None). I wrote you a little example:
from PyQt4 import QtGui, QtCore
import sys
class test(QtGui.QWidget):
def __init__(self,parent=None):
self.widget=QtGui.QWidget.__init__(self, parent)
# Button to add labels
self.btnAdd = QtGui.QPushButton('Add')
self.btnAdd.connect(self.btnAdd, QtCore.SIGNAL('clicked()'),self.btnAddPressed)
# Button to remove labels
self.btnRemove = QtGui.QPushButton('Remove')
self.btnRemove.connect(self.btnRemove, QtCore.SIGNAL('clicked()'), self.btnRemovePressed)
# List to keep track of labels
self.labels=[]
# Layout
self.hbox = QtGui.QHBoxLayout()
self.hbox.addWidget(self.btnAdd)
self.hbox.addWidget(self.btnRemove)
self.setLayout(self.hbox)
self.show()
def btnAddPressed(self):
"""Adds a new label."""
self.labels.append(QtGui.QLabel("lbl"+str(len(self.labels)+1), self))
self.hbox.addWidget(self.labels[-1])
def btnRemovePressed(self):
"""Removes last label."""
self.labels[-1].setParent(None)
self.labels.pop(-1)
def main():
#Creating application
app = QtGui.QApplication(sys.argv)
main_win = test()
sys.exit(app.exec_())
if __name__ == '__main__':
main()