QMainWindow doesn't resize when child widget gets resized

[sasmaster]

I have the following problem.I have a QmainWindow which sets main layout and a widget added to that Layout.
When I resize the widget the QmainWindows remains the same size.

Here is the setup:
In the QmainWindow:
@

 this->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

m_mainLayout = new QVBoxLayout();
m_mainLayout->setAlignment(Qt::AlignHCenter);

m_centralWidget = new QWidget();

m_centralWidget->setLayout(m_mainLayout);
setCentralWidget(m_centralWidget);

this->setMinimumSize(800,600);

m_mainLayout->addWidget(m_GLWidget);

@

Then,at some point m_GLWidget signals it needs to be resized.QmainWindow catches the signal and

reized the m_GLWidget:

@

void MainWindow::ResizeViewportSlot(int w,int h){

  m_GLWidget->setFixedSize(w,h);

  m_GLWidget->updateGeometry();

  this->updateGeometry();

}

@

So as I said.The main window doesn't get resized.What am I doing wrong here?
Thanks.

[JKSH]

[quote author="sasmaster" date="1419353342"]
@
this->setMinimumSize(800,600);
@
[/quote]Did you resize m_GLWidget to something smaller than 800x600?

By the way, I don't think this is related to your problem but "QOpenGLWidget":http://doc.qt.io/qt-5/qopenglwidget.html has replaced QGLWidget in Qt 5.4. You should use that class if possible.

[sasmaster]

No,I resize m_GLWidget to the bigger than 800x600 size.Also ,I am still on Qt 5.2.1 version.

[sasmaster]

I found that if I remove this :

@ this->setMinimumSize(800,600);@

Then the MainWindos does get resized.But in such a case when the app is launched the initial window is collapsed to the area of controls which I don't want.I need on the start up to have it with some default width and height.

[JKSH]

[quote author="sasmaster" date="1419410751"]I found that if I remove this :

@ this->setMinimumSize(800,600);@

Then the MainWindos does get resized.[/quote]Hmm, that sounds strange. Could you please submit a report to https://bugreports.qt-project.org/ and include your test code?

[quote]But in such a case when the app is launched the initial window is collapsed to the area of controls which I don't want.I need on the start up to have it with some default width and height.[/quote]You can call the resize() function when you first create the window.

[kenchan]

so what does your main function look like? It is easiest to use move and resize as soon as you create a window. If it's a main window that is probably best done in main but that depends on your flow.