How to Remove Spacing between widgets added to QHBoxLayout programmetically

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clipboard.png

When using the following code, how can I get rid of the spacing between buttons added to the QHBoxLayout, which is inturn added to QFrame?
Usage of "layout->setSpacing(0)" reduced the space between the buttons, but did not remove the space completely.

Attached is screenshot after executing the below code.

Thanks a lot for your help.

#include <QtGui>
 
int main(int argc,char** argv)
{
   QApplication app(argc,argv);
 
   QMainWindow* window = new QMainWindow();
   QFrame* centralWidget = new QFrame();
   QHBoxLayout* layout = new QHBoxLayout();
 
   window->setCentralWidget(centralWidget);
   centralWidget->setLayout(layout);
 
   layout->addWidget(new QPushButton("Button 1"));
   layout->addWidget(new QPushButton("Button 2"));
 
   window->setWindowTitle("Spacing in HBoxLayout");
 
   layout->addStretch(0);
   layout->setContentsMargins(0,0,0,0);
   layout->setSpacing(0);
 
   window->show();
   return app.exec();
}

#include <QtGui>

int main(int argc,char** argv)
{
   QApplication app(argc,argv);

   QMainWindow* window = new QMainWindow();
   QFrame* centralWidget = new QFrame();
   QHBoxLayout* layout = new QHBoxLayout();

   window->setCentralWidget(centralWidget);
   centralWidget->setLayout(layout);

   layout->addWidget(new QPushButton("Button 1"));
   layout->addWidget(new QPushButton("Button 2"));

   window->setWindowTitle("Spacing in HBoxLayout");

   layout->addStretch(0);
   layout->setContentsMargins(0,0,0,0);
   layout->setSpacing(0);

   window->show();
   return app.exec();
}

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[vividpath]

I found it. Its the border size.
When I edit borders in the css stylesheets, I am able to control the spacing shown in the image.
http://qt-project.org/doc/qt-4.8/sty...html#box-model