QWidget::setLayout error : Attempting to set QLayout [...], which already has a layout

On execution (no compile error) I get on the console

QWidget::setLayout: Attempting to set QLayout "" on CGSearchResult "", which already has a layout

I am using the following code:

CGSearchResult::CGSearchResult(QWidget *parent) : QWidget(parent)
{

    initControls();
    SetTableContent();

}

void CGSearchResult::initControls()
{


   backButton = new QPushButton(tr("&Back"));
   connect(backButton, SIGNAL(clicked()), this, SLOT(showHome()));

   model=new QStandardItemModel();


         QWidget::setFont(QFont("Courier New", 8, QFont::Bold));

        searchTable = new QTableView(this);
        searchTable->showGrid();

        searchTable->resize(720,400);
        searchTable->horizontalHeader()->setDefaultSectionSize(170);
        searchTable->verticalHeader()->setDefaultSectionSize(50);
        searchTable->verticalHeader()->hide();
        searchTable->horizontalHeader()->setResizeMode(QHeaderView::Fixed);
        searchTable->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);


    QGridLayout *layout = new QGridLayout();
    layout->addWidget(backButton, 0, 0, 1, 1);
    layout->addWidget(searchTable, 2, 0, 1, 1);

    setLayout(layout);


}

Solution

http://qt-project.org/doc/qt-4.8/qwidget.html#setLayout

If there already is a layout manager installed on this widget, QWidget won't let you install another. You must first delete the existing layout manager (returned by layout()) before you can call setLayout() with the new layout.