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diff --git a/doc/src/geometry.qdoc b/doc/src/geometry.qdoc deleted file mode 100644 index 9143548..0000000 --- a/doc/src/geometry.qdoc +++ /dev/null @@ -1,150 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). -** Contact: Nokia Corporation (qt-info@nokia.com) -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** No Commercial Usage -** This file contains pre-release code and may not be distributed. -** You may use this file in accordance with the terms and conditions -** contained in the either Technology Preview License Agreement or the -** Beta Release License Agreement. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 2.1 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 2.1 requirements -** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. -** -** In addition, as a special exception, Nokia gives you certain -** additional rights. These rights are described in the Nokia Qt LGPL -** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this -** package. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 3.0 as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL included in the -** packaging of this file. Please review the following information to -** ensure the GNU General Public License version 3.0 requirements will be -** met: http://www.gnu.org/copyleft/gpl.html. -** -** If you are unsure which license is appropriate for your use, please -** contact the sales department at http://qt.nokia.com/contact. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \page geometry.html - \title Window Geometry - \ingroup architecture - \brief An overview of window geometry handling and management. - - QWidget provides several functions that deal with a widget's - geometry. Some of these functions operate on the pure client area - (i.e. the window excluding the window frame), others include the - window frame. The differentiation is done in a way that covers the - most common usage transparently. - - \list - \o \bold{Including the window frame:} - \l{QWidget::x()}{x()}, - \l{QWidget::y()}{y()}, - \l{QWidget::frameGeometry()}{frameGeometry()}, - \l{QWidget::pos()}{pos()}, and - \l{QWidget::move()}{move()}. - \o \bold{Excluding the window frame:} - \l{QWidget::geometry()}{geometry()}, - \l{QWidget::width()}{width()}, - \l{QWidget::height()}{height()}, - \l{QWidget::rect()}{rect()}, and - \l{QWidget::size()}{size()}. - \endlist - - Note that the distinction only matters for decorated top-level - widgets. For all child widgets, the frame geometry is equal to the - widget's client geometry. - - This diagram shows most of the functions in use: - \img geometry.png Geometry diagram - - Topics: - - \tableofcontents - - \section1 X11 Peculiarities - - On X11, a window does not have a frame until the window manager - decorates it. This happens asynchronously at some point in time - after calling QWidget::show() and the first paint event the - window receives, or it does not happen at all. Bear in mind that - X11 is policy-free (others call it flexible). Thus you cannot - make any safe assumption about the decoration frame your window - will get. Basic rule: There's always one user who uses a window - manager that breaks your assumption, and who will complain to - you. - - Furthermore, a toolkit cannot simply place windows on the screen. All - Qt can do is to send certain hints to the window manager. The window - manager, a separate process, may either obey, ignore or misunderstand - them. Due to the partially unclear Inter-Client Communication - Conventions Manual (ICCCM), window placement is handled quite - differently in existing window managers. - - X11 provides no standard or easy way to get the frame geometry - once the window is decorated. Qt solves this problem with nifty - heuristics and clever code that works on a wide range of window - managers that exist today. Don't be surprised if you find one - where QWidget::frameGeometry() returns wrong results though. - - Nor does X11 provide a way to maximize a window. - QWidget::showMaximized() has to emulate the feature. Its result - depends on the result of QWidget::frameGeometry() and the - capability of the window manager to do proper window placement, - neither of which can be guaranteed. - - \section1 Restoring a Window's Geometry - - Since version 4.2, Qt provides functions that saves and restores a - 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. - - The rest of this document describes how to save and restore the - geometry using the geometry properties. On Windows, this is - basically storing the result of QWidget::geometry() and calling - QWidget::setGeometry() in the next session before calling - \l{QWidget::show()}{show()}. On X11, this won't work because an - invisible window doesn't 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, most window managers fail to implement this - feature. - - A workaround is to call \l{QWidget::setGeometry()}{setGeometry()} - after \l{QWidget::show()}{show()}. This has the two disadvantages - that the widget appears at a wrong place for a millisecond - (results in flashing) and that currently only every second window - manager gets it right. A safer 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()}, as demonstrated in the following - code snippets (from the \l{mainwindows/application}{Application} - example): - - \snippet examples/mainwindows/application/mainwindow.cpp 35 - \codeline - \snippet examples/mainwindows/application/mainwindow.cpp 38 - - This method works on Windows, Mac OS X, and most X11 window - managers. -*/ |