c++ - How can I maximize my main window and prevent resize in QT -

i trying maximize main qt window upon running , prevent user resizing it. have tried

int main(int argc, char *argv[]) {     qapplication a(argc, argv);     mainwindow widget;     widget.showmaximized();     widget.show();     return a.exec(); } 

which maximize window, along

mainwindow::mainwindow(qwidget *parent) :     qmainwindow(parent),     ui(new ui::mainwindow) {     this->setwindowflags(this->windowflags() | qt::mswindowsfixedsizedialoghint);     ui->setupui(this); } 

which grey out "restore down", "maximize" button located in title bar in middle of minimize , close window.

but still able drag title bar down unsnap maximized window , readjust size corner , edges.

how can prevent ability unsnap window , no strictly no resizing.

thanks!

if want window frame disappear , maximize-lose-restoredown buttons invisible, can modify ui part of code as:

mainwindow::mainwindow(qwidget *parent) : qmainwindow(parent), ui(new ui::mainwindow) {    this->setwindowflags(this->windowflags() | qt::mswindowsfixedsizedialoghint);    ui->setupui(this);    this->setwindowflags(qt::framelesswindowhint); //makes frame invisible    this->setwindowstate(qt::windowmaximized); //maximizes window }