I have a QScrollArea with a lot of QLineEdits in it. The Problem is that it takes about 2sec on my computer to add 20 new QLineEdits, Take a look at this test-window:
Qt Code: 
  1. TestWidget::TestWidget(QWidget *parent)
  2.  : QWidget(parent)
  3. {
  4.     QHBoxLayout* mainLayout = new QHBoxLayout;
  5.     setLayout(mainLayout);
  6.  
  7.     QPushButton* testButton = new QPushButton("add");
  8.     connect(testButton, SIGNAL(clicked()), this, SLOT(addButtons()));
  9.     mainLayout->addWidget(testButton);
  10.  
  11.     QWidget* textWidget = new QWidget;
  12.  
  13.     QScrollArea* scrollArea = new QScrollArea;
  14.     scrollArea->setWidget(textWidget);
  15.     mainLayout->addWidget(scrollArea);
  16.     scrollArea->setWidgetResizable(true);
  17.  
  18.     layout = new QHBoxLayout;
  19.     textWidget->setLayout(layout);
  20. }
  21. void TestWidget::addButtons() {
  22.     setUpdatesEnabled(false); //doesn't help
  23.     for(int i=0;i<20;i++) {
  24.         QLineEdit* lineEdit = new QLineEdit("foo");
  25.         layout->addWidget(lineEdit);
  26.     }
  27.     setUpdatesEnabled(true);
  28. }
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...i found setUpdatesEnabled but that one doesn't have any effect. What to do else?
Or how could I improve this else?

niko