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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\page restoring-geometry.html
\title Restoring a Window's Geometry
\brief How to save and restore window geometry.
\ingroup best-practices
This document describes how to save and restore a \l{Window
Geometry}{window's geometry} using the geometry properties. On
Windows, this is basically storing the result of
QWindow::geometry() and calling QWindow::setGeometry() in the next
session before calling \l{QWindow::show()}{show()}.
On X11, this might not work because an invisible window does not
have a frame yet. The window manager will decorate the window
later. When this happens, the window shifts towards the
bottom/right corner of the screen depending on the size of the
decoration frame. Although X provides a way to avoid this shift,
some window managers fail to implement this feature.
When using \l{Qt Widgets}, Qt provides functions that saves and restores a
widget window's geometry and state for you. QWidget::saveGeometry()
saves the window geometry and maximized/fullscreen state, while
QWidget::restoreGeometry() restores it. The restore function also
checks if the restored geometry is outside the available screen
geometry, and modifies it as appropriate if it is:
\snippet snippets/code/src_gui_widgets_qmainwindow.cpp 0
\snippet snippets/code/src_gui_widgets_qmainwindow.cpp 1
Another solution is to store both \l{QWidget::pos()}{pos()} and
\l{QWidget::size()}{size()} and to restore the geometry using
\l{QWidget::resize()} and \l{QWidget::move()}{move()} before
calling \l{QWidget::show()}{show()}.
*/