Adding widget into QGridLayout

Waxta

I have problem. I creating widgets, layout and adding them like this:

QGridLayout * layout = new QGridLayout();
    QLineEdit * firstNumberLabel = new QLineEdit("First number layout", this);
    QLineEdit * secondNumberLabel = new QLineEdit("Second number layout", this);

    layout->addWidget(firstNumberLabel, 0, 0);
    layout->addWidget(secondNumberLabel, 1, 0);

    this->setLayout(layout);
    this->setWindowTitle("IEEE Calculator");
    this->setFixedSize(1024, 768);

But I can see only one, last created, widget. What is the problem? I added them correctly, propably...

kshegunov

What does this refer to? What's the class you're doing this in?

Waxta

QMainWindow subclass

kshegunov

Set the layout to the central widget then. Something like this:

QWidget * viewport = new QWidget(this);
setCentralWidget(viewport);

QGridLayout * layout = new QGridLayout(viewport);
viewport->setLayout(layout);

QLineEdit * firstNumberLabel = new QLineEdit("First number layout", this);
QLineEdit * secondNumberLabel = new QLineEdit("Second number layout", this);

layout->addWidget(firstNumberLabel, 0, 0);
layout->addWidget(secondNumberLabel, 1, 0);

setWindowTitle("IEEE Calculator");

mostefa

Hi @Waxta

You are trying to add layout to a widget (MainWindow ) which has already a layout,

Actually according to Qt doc :

http://doc.qt.io/qt-4.8/qmainwindow.html#qt-main-window-framework

"QMainWindow has its own layout to which you can add QToolBars, QDockWidgets, a QMenuBar, and a QStatusBar. The layout has a center area that can be occupied by any kind of widget. You can see an image of the layout below...."

You need to have a central widget (as already suggested by @kshegunov ,and this centralWidget will contain your LineEdits).