Accessing multiple widgets

Question

I have made a GUI using Qt Designer, I have like 20 or more lineEdit widgets, I am looking for the correct way to access all of them without having to access each one...I explain with an example in pseudocode:

This is what I DON'T want:

lineEdit1.setText("Value = 1")
lineEdit2.setText("Value = 2")
lineEdit3.setText("Value = 3")
and so on, up to
lineEdit20.setText("Value = 20")

I am looking for something like THIS:

for i in xrange(1,21):

    lineEdit(i).setText("Value = whatever")

The problem is that, as far as I know, when dragging and dropping widgets, Qt Designer automatically adds a number to the end of the name...lineEdit1, lineEdit2,....so after that I do not know how to access all of them in the code.

Answer 1

If you really want to use the QT designer, I guess your best solution is to simply add widgets to a list. I know this is sub-optimal, but this way you will only have to do it once.

lineEditL = []
lineEditL.append(lineEdit1)
lineEditL.append(lineEdit2)

An other solution is to simply iterate the children. This is explained here, no reason to repeat.

Answer 2

Firstly, you don't have to accept the name that is automatically assigned in Qt Designer. Just set the objectName property to whatever is most suitable.

To iterate over groups of widgets, there are several QObject methods available.

The most powerful is findChildren which can search recursively for objects/widgets based on their class:

for child in self.findChildren(QtGui.QLineEdit):
    child.setValue(value)

and also their objectName:

rgx = QtCore.QRegExp('lineEdit[0-9]+')
for child in self.findChildren(QtGui.QLineEdit, rgx):
    child.setValue(value)

But a simpler technique would be to use Qt Designer to put all the widgets inside a container widget (such as a QWidget, QFrame, QGroupBox, etc), and then use the non-recursive children method to loop over them:

for index, child in enumerate(self.groupBox.children()):
    child.setValue(value[index])

You might also want to consider using a QFormLayout, which provides a more structured way of doing things. This is available in Qt Designer: just drag and drop a Form Layout onto your main form and then use Add form layout row from the right-click menu to add widgets to it.

Answer 3

QWidget *pWin = QApplication::activeWindow();
for( int i=1; i<=21; i++ ) {
    QString strName ="LineEdit"+QString::number(i);
    QLineEdit *le = pWin->findChild<QLineEdit *>(strName);
    if( le ) le->setText("Value = "+Qstring::number(i) );
}