Qt 窗口设置

===========设置默认大小================================================================================

void QWidget::setWindowState ( Qt::WindowStates windowState )

The states are

Constant	Value	Description
Qt::WindowNoState	0x00000000	The window has no state set (in normal state).
Qt::WindowMinimized	0x00000001	The window is minimized (i.e. iconified).
Qt::WindowMaximized	0x00000002	The window is maximized with a frame around it.
Qt::WindowFullScreen	0x00000004	The window fills the entire screen without any frame around it.
Qt::WindowActive	0x00000008	The window is the active window, i.e. it has keyboard focus.

===========设置固定大小================================================================================

void QWidget::setFixedSize ( int w, int h )

===========设置最大化最小化边框策略=====================================================================
void QWidget::setWindowFlags ( Qt::WindowFlags type )

Qt::FrameWindowHint:没有边框的窗口
Qt::WindowStaysOnTopHint://总在最上面的窗口
Qt::CustomizeWindowHint://自定义窗口标题栏,以下标志必须与这个标志一起使用才有效,否则窗口将有默认的标题栏
Qt::WindowTitleHint:显示窗口标题栏
Qt::WindowSystemMenuHint://显示系统菜单
Qt::WindowMinimizeButtonHint://显示最小化按钮
Qt::WindowMaximizeButtonHint://显示最大化按钮
Qt::WindowMinMaxButtonsHint://显示最小化按钮和最大化按钮
Qt::WindowCloseButtonHint://显示关闭按钮
setWindowFlags(Qt::FramelessWindowHint);直接隐藏掉。。。

===========设置窗口位置至屏幕中央=======================================================================

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();// 注意：一定要先 show 再 move，否则 move 无效

    w.move ((QApplication::desktop()->width() - w.width())/2,
            (QApplication::desktop()->height() - w.height())/2);

    return a.exec();
}

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