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diff --git a/doc/src/classes/qdesktopwidget.qdoc b/doc/src/classes/qdesktopwidget.qdoc new file mode 100644 index 000000000..56a882d61 --- /dev/null +++ b/doc/src/classes/qdesktopwidget.qdoc @@ -0,0 +1,266 @@ +/**************************************************************************** +** +** 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://www.qtsoftware.com/contact. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \class QDesktopWidget + \brief The QDesktopWidget class provides access to screen information on multi-head systems. + + \ingroup advanced + \ingroup desktop + \ingroup environment + \mainclass + + QApplication::desktop() function should be used to get an instance + of the QDesktopWidget. + + Systems with more than one graphics card and monitor can manage the + physical screen space available either as multiple desktops, or as a + large virtual desktop, which usually has the size of the bounding + rectangle of all the screens (see virtualDesktop). For an + application, one of the available screens is the primary screen, i.e. + the screen where the main widget resides (see primaryScreen). All + windows opened in the context of the application should be + constrained to the boundaries of the primary screen; for example, + it would be inconvenient if a dialog box popped up on a different + screen, or split over two screens. + + The QDesktopWidget provides information about the geometry of the + available screens with screenGeometry(). The number of screens + available is returned by screenCount, and the screenCountChanged + signal is emitted when screens are added or removed during runtime. + The screen number that a particular point or widget is located in + is returned by screenNumber(). + + Widgets provided by Qt use this class, for example, to place + tooltips, menus and dialog boxes according to the parent or + application widget. Applications can use this class to save window + positions, or to place child widgets and dialogs on one particular + screen. + + \img qdesktopwidget.png Managing Multiple Screens + + In the illustration above, Application One's primary screen is + screen 0, and App Two's primary screen is screen 1. + + \target multiple screens note + \note QDesktopWidget inherits the QWidget properties, width() and + height(), which specify the size of the desktop. However, for + desktops with multiple screens, the size of the desktop is the union + of all the screen sizes, so width() and height() should \e not be + used for computing the size of a widget to be placed on one of the + screens. The correct width and height values are obtained using + availableGeometry() or screenGeometry() for a particular screen. + + \sa QApplication, QApplication::desktop(), QX11Info::appRootWindow() +*/ + +/*! + \fn QDesktopWidget::QDesktopWidget() + + \internal + + Creates the desktop widget. + + If the system supports a virtual desktop, this widget will have + the size of the virtual desktop; otherwise this widget will have + the size of the primary screen. + + Instead of using QDesktopWidget directly, use QApplication::desktop(). +*/ + +/*! + \fn QDesktopWidget::~QDesktopWidget() + + \internal + + Destroys the desktop widget and frees any allocated resources. +*/ + +/*! + \fn int QDesktopWidget::numScreens() const + + Returns the number of available screens. + + \obsolete + + This function is deprecated. Use screenCount instead. + + \sa primaryScreen +*/ + +/*! + \fn QWidget *QDesktopWidget::screen(int screen) + + Returns a widget that represents the screen with index \a screen + (a value of -1 means the default screen). + + If the system uses a virtual desktop, the returned widget will + have the geometry of the entire virtual desktop; i.e., bounding + every \a screen. + + \sa primaryScreen, screenCount, virtualDesktop +*/ + +/*! + \fn const QRect QDesktopWidget::availableGeometry(int screen) const + + Returns the available geometry of the screen with index \a screen. What + is available will be subrect of screenGeometry() based on what the + platform decides is available (for example excludes the dock and menu bar + on Mac OS X, or the task bar on Windows). The default screen is used if + \a screen is -1. + + \sa screenNumber(), screenGeometry() +*/ + +/*! + \fn const QRect QDesktopWidget::availableGeometry(const QWidget *widget) const + \overload + + Returns the available geometry of the screen which contains \a widget. + + \sa screenGeometry() +*/ + +/*! + \fn const QRect QDesktopWidget::availableGeometry(const QPoint &p) const + \overload + + Returns the available geometry of the screen which contains \a p. + + \sa screenGeometry() +*/ + + +/*! + \fn const QRect QDesktopWidget::screenGeometry(int screen) const + + Returns the geometry of the screen with index \a screen. The default + screen is used if \a screen is -1. + + \sa screenNumber() +*/ + +/*! + \fn const QRect QDesktopWidget::screenGeometry(const QWidget *widget) const + \overload + + Returns the geometry of the screen which contains \a widget. +*/ + +/*! + \fn const QRect QDesktopWidget::screenGeometry(const QPoint &p) const + \overload + + Returns the geometry of the screen which contains \a p. +*/ + + +/*! + \fn int QDesktopWidget::screenNumber(const QWidget *widget) const + + Returns the index of the screen that contains the largest + part of \a widget, or -1 if the widget not on a screen. + + \sa primaryScreen +*/ + +/*! + \fn int QDesktopWidget::screenNumber(const QPoint &point) const + + \overload + Returns the index of the screen that contains the \a point, or the + screen which is the shortest distance from the \a point. + + \sa primaryScreen +*/ + +/*! + \fn void QDesktopWidget::resizeEvent(QResizeEvent *event) + \reimp +*/ + +/*! + \fn void QDesktopWidget::resized(int screen) + + This signal is emitted when the size of \a screen changes. +*/ + +/*! + \fn void QDesktopWidget::workAreaResized(int screen) + + This signal is emitted when the work area available on \a screen changes. +*/ + +/*! + \property QDesktopWidget::screenCount + \brief the number of screens currently available on the system. + + \since 4.6 + + \sa screenCountChanged() +*/ + +/*! + \property QDesktopWidget::primaryScreen + \brief the index of the screen that is configured to be the primary screen + on the system. +*/ + +/*! + \property QDesktopWidget::virtualDesktop + + \brief if the system manages the available screens in a virtual desktop. + + For virtual desktops, screen() will always return the same widget. + The size of the virtual desktop is the size of this desktop + widget. +*/ + +/*! + \fn void QDesktopWidget::screenCountChanged(int newCount) + + \since 4.6 + + This signal is emitted when the number of screens changes to \a newCount. + + \sa screenCount +*/ |