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qicon.cpp
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qicon.cpp
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/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2015 Olivier Goffart <[email protected]>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qicon.h"
#include "qicon_p.h"
#include "qiconengine.h"
#include "qiconengineplugin.h"
#include "qimagereader.h"
#include "private/qfactoryloader_p.h"
#include "private/qiconloader_p.h"
#include "qpainter.h"
#include "qfileinfo.h"
#if QT_CONFIG(mimetype)
#include <qmimedatabase.h>
#include <qmimetype.h>
#endif
#include "qpixmapcache.h"
#include "qvariant.h"
#include "qcache.h"
#include "qdebug.h"
#include "qdir.h"
#include "qpalette.h"
#include "qmath.h"
#include "private/qhexstring_p.h"
#include "private/qguiapplication_p.h"
#include "qpa/qplatformtheme.h"
#ifndef QT_NO_ICON
QT_BEGIN_NAMESPACE
/*!
\enum QIcon::Mode
This enum type describes the mode for which a pixmap is intended
to be used. The currently defined modes are:
\value Normal
Display the pixmap when the user is
not interacting with the icon, but the
functionality represented by the icon is available.
\value Disabled
Display the pixmap when the
functionality represented by the icon is not available.
\value Active
Display the pixmap when the
functionality represented by the icon is available and
the user is interacting with the icon, for example, moving the
mouse over it or clicking it.
\value Selected
Display the pixmap when the item represented by the icon is
selected.
*/
/*!
\enum QIcon::State
This enum describes the state for which a pixmap is intended to be
used. The \e state can be:
\value Off Display the pixmap when the widget is in an "off" state
\value On Display the pixmap when the widget is in an "on" state
*/
static int nextSerialNumCounter()
{
static QBasicAtomicInt serial = Q_BASIC_ATOMIC_INITIALIZER(0);
return 1 + serial.fetchAndAddRelaxed(1);
}
static void qt_cleanup_icon_cache();
namespace {
struct IconCache : public QCache<QString, QIcon>
{
IconCache()
{
// ### note: won't readd if QApplication is re-created!
qAddPostRoutine(qt_cleanup_icon_cache);
}
};
}
Q_GLOBAL_STATIC(IconCache, qtIconCache)
static void qt_cleanup_icon_cache()
{
qtIconCache()->clear();
}
/*! \internal
Returns the effective device pixel ratio, using
the provided window pointer if possible.
if Qt::AA_UseHighDpiPixmaps is not set this function
returns 1.0 to keep non-hihdpi aware code working.
*/
static qreal qt_effective_device_pixel_ratio(QWindow *window = nullptr)
{
if (!qApp->testAttribute(Qt::AA_UseHighDpiPixmaps))
return qreal(1.0);
if (window)
return window->devicePixelRatio();
return qApp->devicePixelRatio(); // Don't know which window to target.
}
QIconPrivate::QIconPrivate(QIconEngine *e)
: engine(e), ref(1),
serialNum(nextSerialNumCounter()),
detach_no(0),
is_mask(false)
{
}
/*! \internal
Computes the displayDevicePixelRatio for a pixmap.
If displayDevicePixelRatio is 1.0 the reurned value is 1.0, always.
For a displayDevicePixelRatio of 2.0 the returned value will be between
1.0 and 2.0, depending on requestedSize and actualsize:
* If actualsize < requestedSize : 1.0 (not enough pixels for a normal-dpi pixmap)
* If actualsize == requestedSize * 2.0 : 2.0 (enough pixels for a high-dpi pixmap)
* else : a scaled value between 1.0 and 2.0. (pixel count is between normal-dpi and high-dpi)
*/
qreal QIconPrivate::pixmapDevicePixelRatio(qreal displayDevicePixelRatio, const QSize &requestedSize, const QSize &actualSize)
{
QSize targetSize = requestedSize * displayDevicePixelRatio;
if ((actualSize.width() == targetSize.width() && actualSize.height() <= targetSize.height()) ||
(actualSize.width() <= targetSize.width() && actualSize.height() == targetSize.height())) {
// Correctly scaled for dpr, just having different aspect ratio
return displayDevicePixelRatio;
}
qreal scale = 0.5 * (qreal(actualSize.width()) / qreal(targetSize.width()) +
qreal(actualSize.height() / qreal(targetSize.height())));
return qMax(qreal(1.0), displayDevicePixelRatio *scale);
}
QPixmapIconEngine::QPixmapIconEngine()
{
}
QPixmapIconEngine::QPixmapIconEngine(const QPixmapIconEngine &other)
: QIconEngine(other), pixmaps(other.pixmaps)
{
}
QPixmapIconEngine::~QPixmapIconEngine()
{
}
void QPixmapIconEngine::paint(QPainter *painter, const QRect &rect, QIcon::Mode mode, QIcon::State state)
{
qreal dpr = 1.0;
if (QCoreApplication::testAttribute(Qt::AA_UseHighDpiPixmaps)) {
auto paintDevice = painter->device();
dpr = paintDevice ? paintDevice->devicePixelRatioF() : qApp->devicePixelRatio();
}
const QSize pixmapSize = rect.size() * dpr;
QPixmap px = pixmap(pixmapSize, mode, state);
painter->drawPixmap(rect, px);
}
static inline int area(const QSize &s) { return s.width() * s.height(); }
// returns the smallest of the two that is still larger than or equal to size.
static QPixmapIconEngineEntry *bestSizeMatch( const QSize &size, QPixmapIconEngineEntry *pa, QPixmapIconEngineEntry *pb)
{
int s = area(size);
if (pa->size == QSize() && pa->pixmap.isNull()) {
pa->pixmap = QPixmap(pa->fileName);
pa->size = pa->pixmap.size();
}
int a = area(pa->size);
if (pb->size == QSize() && pb->pixmap.isNull()) {
pb->pixmap = QPixmap(pb->fileName);
pb->size = pb->pixmap.size();
}
int b = area(pb->size);
int res = a;
if (qMin(a,b) >= s)
res = qMin(a,b);
else
res = qMax(a,b);
if (res == a)
return pa;
return pb;
}
QPixmapIconEngineEntry *QPixmapIconEngine::tryMatch(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
QPixmapIconEngineEntry *pe = nullptr;
for (int i = 0; i < pixmaps.count(); ++i)
if (pixmaps.at(i).mode == mode && pixmaps.at(i).state == state) {
if (pe)
pe = bestSizeMatch(size, &pixmaps[i], pe);
else
pe = &pixmaps[i];
}
return pe;
}
QPixmapIconEngineEntry *QPixmapIconEngine::bestMatch(const QSize &size, QIcon::Mode mode, QIcon::State state, bool sizeOnly)
{
QPixmapIconEngineEntry *pe = tryMatch(size, mode, state);
while (!pe){
QIcon::State oppositeState = (state == QIcon::On) ? QIcon::Off : QIcon::On;
if (mode == QIcon::Disabled || mode == QIcon::Selected) {
QIcon::Mode oppositeMode = (mode == QIcon::Disabled) ? QIcon::Selected : QIcon::Disabled;
if ((pe = tryMatch(size, QIcon::Normal, state)))
break;
if ((pe = tryMatch(size, QIcon::Active, state)))
break;
if ((pe = tryMatch(size, mode, oppositeState)))
break;
if ((pe = tryMatch(size, QIcon::Normal, oppositeState)))
break;
if ((pe = tryMatch(size, QIcon::Active, oppositeState)))
break;
if ((pe = tryMatch(size, oppositeMode, state)))
break;
if ((pe = tryMatch(size, oppositeMode, oppositeState)))
break;
} else {
QIcon::Mode oppositeMode = (mode == QIcon::Normal) ? QIcon::Active : QIcon::Normal;
if ((pe = tryMatch(size, oppositeMode, state)))
break;
if ((pe = tryMatch(size, mode, oppositeState)))
break;
if ((pe = tryMatch(size, oppositeMode, oppositeState)))
break;
if ((pe = tryMatch(size, QIcon::Disabled, state)))
break;
if ((pe = tryMatch(size, QIcon::Selected, state)))
break;
if ((pe = tryMatch(size, QIcon::Disabled, oppositeState)))
break;
if ((pe = tryMatch(size, QIcon::Selected, oppositeState)))
break;
}
if (!pe)
return pe;
}
if (sizeOnly ? (pe->size.isNull() || !pe->size.isValid()) : pe->pixmap.isNull()) {
pe->pixmap = QPixmap(pe->fileName);
if (!pe->pixmap.isNull())
pe->size = pe->pixmap.size();
}
return pe;
}
QPixmap QPixmapIconEngine::pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
QPixmap pm;
QPixmapIconEngineEntry *pe = bestMatch(size, mode, state, false);
if (pe)
pm = pe->pixmap;
if (pm.isNull()) {
int idx = pixmaps.count();
while (--idx >= 0) {
if (pe == &pixmaps.at(idx)) {
pixmaps.remove(idx);
break;
}
}
if (pixmaps.isEmpty())
return pm;
else
return pixmap(size, mode, state);
}
QSize actualSize = pm.size();
if (!actualSize.isNull() && (actualSize.width() > size.width() || actualSize.height() > size.height()))
actualSize.scale(size, Qt::KeepAspectRatio);
QString key = QLatin1String("qt_")
% HexString<quint64>(pm.cacheKey())
% HexString<uint>(pe ? pe->mode : QIcon::Normal)
% HexString<quint64>(QGuiApplication::palette().cacheKey())
% HexString<uint>(actualSize.width())
% HexString<uint>(actualSize.height());
if (mode == QIcon::Active) {
if (QPixmapCache::find(key % HexString<uint>(mode), &pm))
return pm; // horray
if (QPixmapCache::find(key % HexString<uint>(QIcon::Normal), &pm)) {
QPixmap active = pm;
if (QGuiApplication *guiApp = qobject_cast<QGuiApplication *>(qApp))
active = static_cast<QGuiApplicationPrivate*>(QObjectPrivate::get(guiApp))->applyQIconStyleHelper(QIcon::Active, pm);
if (pm.cacheKey() == active.cacheKey())
return pm;
}
}
if (!QPixmapCache::find(key % HexString<uint>(mode), &pm)) {
if (pm.size() != actualSize)
pm = pm.scaled(actualSize, Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
if (pe->mode != mode && mode != QIcon::Normal) {
QPixmap generated = pm;
if (QGuiApplication *guiApp = qobject_cast<QGuiApplication *>(qApp))
generated = static_cast<QGuiApplicationPrivate*>(QObjectPrivate::get(guiApp))->applyQIconStyleHelper(mode, pm);
if (!generated.isNull())
pm = generated;
}
QPixmapCache::insert(key % HexString<uint>(mode), pm);
}
return pm;
}
QSize QPixmapIconEngine::actualSize(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
QSize actualSize;
if (QPixmapIconEngineEntry *pe = bestMatch(size, mode, state, true))
actualSize = pe->size;
if (actualSize.isNull())
return actualSize;
if (!actualSize.isNull() && (actualSize.width() > size.width() || actualSize.height() > size.height()))
actualSize.scale(size, Qt::KeepAspectRatio);
return actualSize;
}
void QPixmapIconEngine::addPixmap(const QPixmap &pixmap, QIcon::Mode mode, QIcon::State state)
{
if (!pixmap.isNull()) {
QPixmapIconEngineEntry *pe = tryMatch(pixmap.size(), mode, state);
if(pe && pe->size == pixmap.size()) {
pe->pixmap = pixmap;
pe->fileName.clear();
} else {
pixmaps += QPixmapIconEngineEntry(pixmap, mode, state);
}
}
}
// Read out original image depth as set by ICOReader
static inline int origIcoDepth(const QImage &image)
{
const QString s = image.text(QStringLiteral("_q_icoOrigDepth"));
return s.isEmpty() ? 32 : s.toInt();
}
static inline int findBySize(const QList<QImage> &images, const QSize &size)
{
for (int i = 0; i < images.size(); ++i) {
if (images.at(i).size() == size)
return i;
}
return -1;
}
// Convenience class providing a bool read() function.
namespace {
class ImageReader
{
public:
ImageReader(const QString &fileName) : m_reader(fileName), m_atEnd(false) {}
QByteArray format() const { return m_reader.format(); }
bool read(QImage *image)
{
if (m_atEnd)
return false;
*image = m_reader.read();
if (!image->size().isValid()) {
m_atEnd = true;
return false;
}
m_atEnd = !m_reader.jumpToNextImage();
return true;
}
private:
QImageReader m_reader;
bool m_atEnd;
};
} // namespace
void QPixmapIconEngine::addFile(const QString &fileName, const QSize &size, QIcon::Mode mode, QIcon::State state)
{
if (fileName.isEmpty())
return;
const QString abs = fileName.startsWith(QLatin1Char(':')) ? fileName : QFileInfo(fileName).absoluteFilePath();
const bool ignoreSize = !size.isValid();
ImageReader imageReader(abs);
const QByteArray format = imageReader.format();
if (format.isEmpty()) // Device failed to open or unsupported format.
return;
QImage image;
if (format != "ico") {
if (ignoreSize) { // No size specified: Add all images.
while (imageReader.read(&image))
pixmaps += QPixmapIconEngineEntry(abs, image, mode, state);
} else {
// Try to match size. If that fails, add a placeholder with the filename and empty pixmap for the size.
while (imageReader.read(&image) && image.size() != size) {}
pixmaps += image.size() == size ?
QPixmapIconEngineEntry(abs, image, mode, state) : QPixmapIconEngineEntry(abs, size, mode, state);
}
return;
}
// Special case for reading Windows ".ico" files. Historically (QTBUG-39287),
// these files may contain low-resolution images. As this information is lost,
// ICOReader sets the original format as an image text key value. Read all matching
// images into a list trying to find the highest quality per size.
QList<QImage> icoImages;
while (imageReader.read(&image)) {
if (ignoreSize || image.size() == size) {
const int position = findBySize(icoImages, image.size());
if (position >= 0) { // Higher quality available? -> replace.
if (origIcoDepth(image) > origIcoDepth(icoImages.at(position)))
icoImages[position] = image;
} else {
icoImages.append(image);
}
}
}
for (const QImage &i : qAsConst(icoImages))
pixmaps += QPixmapIconEngineEntry(abs, i, mode, state);
if (icoImages.isEmpty() && !ignoreSize) // Add placeholder with the filename and empty pixmap for the size.
pixmaps += QPixmapIconEngineEntry(abs, size, mode, state);
}
QString QPixmapIconEngine::key() const
{
return QLatin1String("QPixmapIconEngine");
}
QIconEngine *QPixmapIconEngine::clone() const
{
return new QPixmapIconEngine(*this);
}
bool QPixmapIconEngine::read(QDataStream &in)
{
int num_entries;
QPixmap pm;
QString fileName;
QSize sz;
uint mode;
uint state;
in >> num_entries;
for (int i=0; i < num_entries; ++i) {
if (in.atEnd()) {
pixmaps.clear();
return false;
}
in >> pm;
in >> fileName;
in >> sz;
in >> mode;
in >> state;
if (pm.isNull()) {
addFile(fileName, sz, QIcon::Mode(mode), QIcon::State(state));
} else {
QPixmapIconEngineEntry pe(fileName, sz, QIcon::Mode(mode), QIcon::State(state));
pe.pixmap = pm;
pixmaps += pe;
}
}
return true;
}
bool QPixmapIconEngine::write(QDataStream &out) const
{
int num_entries = pixmaps.size();
out << num_entries;
for (int i=0; i < num_entries; ++i) {
if (pixmaps.at(i).pixmap.isNull())
out << QPixmap(pixmaps.at(i).fileName);
else
out << pixmaps.at(i).pixmap;
out << pixmaps.at(i).fileName;
out << pixmaps.at(i).size;
out << (uint) pixmaps.at(i).mode;
out << (uint) pixmaps.at(i).state;
}
return true;
}
void QPixmapIconEngine::virtual_hook(int id, void *data)
{
switch (id) {
case QIconEngine::AvailableSizesHook: {
QIconEngine::AvailableSizesArgument &arg =
*reinterpret_cast<QIconEngine::AvailableSizesArgument*>(data);
arg.sizes.clear();
for (int i = 0; i < pixmaps.size(); ++i) {
QPixmapIconEngineEntry &pe = pixmaps[i];
if (pe.size == QSize() && pe.pixmap.isNull()) {
pe.pixmap = QPixmap(pe.fileName);
pe.size = pe.pixmap.size();
}
if (pe.mode == arg.mode && pe.state == arg.state && !pe.size.isEmpty())
arg.sizes.push_back(pe.size);
}
break;
}
default:
QIconEngine::virtual_hook(id, data);
}
}
Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
(QIconEngineFactoryInterface_iid, QLatin1String("/iconengines"), Qt::CaseInsensitive))
QFactoryLoader *qt_iconEngineFactoryLoader()
{
return loader();
}
/*!
\class QIcon
\brief The QIcon class provides scalable icons in different modes
and states.
\ingroup painting
\ingroup shared
\inmodule QtGui
A QIcon can generate smaller, larger, active, and disabled pixmaps
from the set of pixmaps it is given. Such pixmaps are used by Qt
widgets to show an icon representing a particular action.
The simplest use of QIcon is to create one from a QPixmap file or
resource, and then use it, allowing Qt to work out all the required
icon styles and sizes. For example:
\snippet code/src_gui_image_qicon.cpp 0
To undo a QIcon, simply set a null icon in its place:
\snippet code/src_gui_image_qicon.cpp 1
Use the QImageReader::supportedImageFormats() and
QImageWriter::supportedImageFormats() functions to retrieve a
complete list of the supported file formats.
When you retrieve a pixmap using pixmap(QSize, Mode, State), and no
pixmap for this given size, mode and state has been added with
addFile() or addPixmap(), then QIcon will generate one on the
fly. This pixmap generation happens in a QIconEngine. The default
engine scales pixmaps down if required, but never up, and it uses
the current style to calculate a disabled appearance. By using
custom icon engines, you can customize every aspect of generated
icons. With QIconEnginePlugin it is possible to register different
icon engines for different file suffixes, making it possible for
third parties to provide additional icon engines to those included
with Qt.
\note Since Qt 4.2, an icon engine that supports SVG is included.
\section1 Making Classes that Use QIcon
If you write your own widgets that have an option to set a small
pixmap, consider allowing a QIcon to be set for that pixmap. The
Qt class QToolButton is an example of such a widget.
Provide a method to set a QIcon, and when you draw the icon, choose
whichever pixmap is appropriate for the current state of your widget.
For example:
\snippet code/src_gui_image_qicon.cpp 2
You might also make use of the \c Active mode, perhaps making your
widget \c Active when the mouse is over the widget (see \l
QWidget::enterEvent()), while the mouse is pressed pending the
release that will activate the function, or when it is the currently
selected item. If the widget can be toggled, the "On" mode might be
used to draw a different icon.
\image icon.png QIcon
\note QIcon needs a QGuiApplication instance before the icon is created.
\section1 High DPI Icons
There are two ways that QIcon supports \l {High DPI Displays}{high DPI}
icons: via \l addFile() and \l fromTheme().
\l addFile() is useful if you have your own custom directory structure and do
not need to use the \l {Icon Theme Specification}{freedesktop.org Icon Theme
Specification}. Icons created via this approach use Qt's \l {High Resolution
Versions of Images}{"@nx" high DPI syntax}.
Using \l fromTheme() is necessary if you plan on following the Icon Theme
Specification. To make QIcon use the high DPI version of an image, add an
additional entry to the appropriate \c index.theme file:
\badcode
[Icon Theme]
Name=Test
Comment=Test Theme
Directories=32x32/actions,32x32@2/actions
[32x32/actions]
Size=32
Context=Actions
Type=Fixed
# High DPI version of the entry above.
[32x32@2/actions]
Size=32
Scale=2
Type=Fixed
\endcode
Your icon theme directory would then look something like this:
\badcode
├── 32x32
│ └── actions
│ └── appointment-new.png
├── 32x32@2
│ └── actions
│ └── appointment-new.png
└── index.theme
\endcode
\sa {fowler}{GUI Design Handbook: Iconic Label}, {Icons Example}
*/
/*!
Constructs a null icon.
*/
QIcon::QIcon() noexcept
: d(nullptr)
{
}
/*!
Constructs an icon from a \a pixmap.
*/
QIcon::QIcon(const QPixmap &pixmap)
:d(nullptr)
{
addPixmap(pixmap);
}
/*!
Constructs a copy of \a other. This is very fast.
*/
QIcon::QIcon(const QIcon &other)
:d(other.d)
{
if (d)
d->ref.ref();
}
/*!
\fn QIcon::QIcon(QIcon &&other)
Move-constructs a QIcon instance, making it point to the same object
that \a other was pointing to.
*/
/*!
Constructs an icon from the file with the given \a fileName. The
file will be loaded on demand.
If \a fileName contains a relative path (e.g. the filename only)
the relevant file must be found relative to the runtime working
directory.
The file name can refer to an actual file on disk or to
one of the application's embedded resources. See the
\l{resources.html}{Resource System} overview for details on how to
embed images and other resource files in the application's
executable.
Use the QImageReader::supportedImageFormats() and
QImageWriter::supportedImageFormats() functions to retrieve a
complete list of the supported file formats.
*/
QIcon::QIcon(const QString &fileName)
: d(nullptr)
{
addFile(fileName);
}
/*!
Creates an icon with a specific icon \a engine. The icon takes
ownership of the engine.
*/
QIcon::QIcon(QIconEngine *engine)
:d(new QIconPrivate(engine))
{
}
/*!
Destroys the icon.
*/
QIcon::~QIcon()
{
if (d && !d->ref.deref())
delete d;
}
/*!
Assigns the \a other icon to this icon and returns a reference to
this icon.
*/
QIcon &QIcon::operator=(const QIcon &other)
{
if (other.d)
other.d->ref.ref();
if (d && !d->ref.deref())
delete d;
d = other.d;
return *this;
}
/*!
\fn QIcon &QIcon::operator=(QIcon &&other)
Move-assigns \a other to this QIcon instance.
\since 5.2
*/
/*!
\fn void QIcon::swap(QIcon &other)
\since 4.8
Swaps icon \a other with this icon. This operation is very
fast and never fails.
*/
/*!
Returns the icon as a QVariant.
*/
QIcon::operator QVariant() const
{
return QVariant(QMetaType::QIcon, this);
}
/*!
Returns a number that identifies the contents of this QIcon
object. Distinct QIcon objects can have the same key if
they refer to the same contents.
\since 4.3
The cacheKey() will change when the icon is altered via
addPixmap() or addFile().
Cache keys are mostly useful in conjunction with caching.
\sa QPixmap::cacheKey()
*/
qint64 QIcon::cacheKey() const
{
if (!d)
return 0;
return (((qint64) d->serialNum) << 32) | ((qint64) (d->detach_no));
}
/*!
Returns a pixmap with the requested \a size, \a mode, and \a
state, generating one if necessary. The pixmap might be smaller than
requested, but never larger.
Setting the Qt::AA_UseHighDpiPixmaps application attribute enables this
function to return pixmaps that are larger than the requested size. Such
images will have a devicePixelRatio larger than 1.
\sa actualSize(), paint()
*/
QPixmap QIcon::pixmap(const QSize &size, Mode mode, State state) const
{
if (!d)
return QPixmap();
return pixmap(nullptr, size, mode, state);
}
/*!
\fn QPixmap QIcon::pixmap(int w, int h, Mode mode = Normal, State state = Off) const
\overload
Returns a pixmap of size QSize(\a w, \a h). The pixmap might be smaller than
requested, but never larger.
Setting the Qt::AA_UseHighDpiPixmaps application attribute enables this
function to return pixmaps that are larger than the requested size. Such
images will have a devicePixelRatio larger than 1.
*/
/*!
\fn QPixmap QIcon::pixmap(int extent, Mode mode = Normal, State state = Off) const
\overload
Returns a pixmap of size QSize(\a extent, \a extent). The pixmap might be smaller
than requested, but never larger.
Setting the Qt::AA_UseHighDpiPixmaps application attribute enables this
function to return pixmaps that are larger than the requested size. Such
images will have a devicePixelRatio larger than 1.
*/
/*! Returns the actual size of the icon for the requested \a size, \a
mode, and \a state. The result might be smaller than requested, but
never larger. The returned size is in device-independent pixels (This
is relevant for high-dpi pixmaps.)
\sa pixmap(), paint()
*/
QSize QIcon::actualSize(const QSize &size, Mode mode, State state) const
{
if (!d)
return QSize();
return actualSize(nullptr, size, mode, state);
}
/*!
\since 5.1
Returns a pixmap with the requested \a window \a size, \a mode, and \a
state, generating one if necessary.
The pixmap can be smaller than the requested size. If \a window is on
a high-dpi display the pixmap can be larger. In that case it will have
a devicePixelRatio larger than 1.
\sa actualSize(), paint()
*/
QPixmap QIcon::pixmap(QWindow *window, const QSize &size, Mode mode, State state) const
{
if (!d)
return QPixmap();
qreal devicePixelRatio = qt_effective_device_pixel_ratio(window);
// Handle the simple normal-dpi case:
if (!(devicePixelRatio > 1.0)) {
QPixmap pixmap = d->engine->pixmap(size, mode, state);
pixmap.setDevicePixelRatio(1.0);
return pixmap;
}
// Try get a pixmap that is big enough to be displayed at device pixel resolution.
QIconEngine::ScaledPixmapArgument scalePixmapArg = { size * devicePixelRatio, mode, state, devicePixelRatio, QPixmap() };
d->engine->virtual_hook(QIconEngine::ScaledPixmapHook, reinterpret_cast<void*>(&scalePixmapArg));
scalePixmapArg.pixmap.setDevicePixelRatio(d->pixmapDevicePixelRatio(devicePixelRatio, size, scalePixmapArg.pixmap.size()));
return scalePixmapArg.pixmap;
}
/*!
\since 5.1
Returns the actual size of the icon for the requested \a window \a size, \a
mode, and \a state.
The pixmap can be smaller than the requested size. The returned size
is in device-independent pixels (This is relevant for high-dpi pixmaps.)
\sa actualSize(), pixmap(), paint()
*/
QSize QIcon::actualSize(QWindow *window, const QSize &size, Mode mode, State state) const
{
if (!d)
return QSize();
qreal devicePixelRatio = qt_effective_device_pixel_ratio(window);
// Handle the simple normal-dpi case:
if (!(devicePixelRatio > 1.0))
return d->engine->actualSize(size, mode, state);
QSize actualSize = d->engine->actualSize(size * devicePixelRatio, mode, state);
return actualSize / d->pixmapDevicePixelRatio(devicePixelRatio, size, actualSize);
}
/*!
Uses the \a painter to paint the icon with specified \a alignment,
required \a mode, and \a state into the rectangle \a rect.
\sa actualSize(), pixmap()
*/
void QIcon::paint(QPainter *painter, const QRect &rect, Qt::Alignment alignment, Mode mode, State state) const
{
if (!d || !painter)
return;
// Copy of QStyle::alignedRect
const QSize size = d->engine->actualSize(rect.size(), mode, state);
alignment = QGuiApplicationPrivate::visualAlignment(painter->layoutDirection(), alignment);
int x = rect.x();
int y = rect.y();
int w = size.width();
int h = size.height();
if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
y += rect.size().height()/2 - h/2;
else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
y += rect.size().height() - h;
if ((alignment & Qt::AlignRight) == Qt::AlignRight)
x += rect.size().width() - w;
else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
x += rect.size().width()/2 - w/2;
QRect alignedRect(x, y, w, h);
d->engine->paint(painter, alignedRect, mode, state);
}
/*!
\fn void QIcon::paint(QPainter *painter, int x, int y, int w, int h, Qt::Alignment alignment,
Mode mode, State state) const
\overload
Paints the icon into the rectangle QRect(\a x, \a y, \a w, \a h).
*/
/*!
Returns \c true if the icon is empty; otherwise returns \c false.
An icon is empty if it has neither a pixmap nor a filename.
Note: Even a non-null icon might not be able to create valid
pixmaps, eg. if the file does not exist or cannot be read.
*/
bool QIcon::isNull() const
{
return !d || d->engine->isNull();
}
/*!\internal
*/
bool QIcon::isDetached() const
{
return !d || d->ref.loadRelaxed() == 1;
}
/*! \internal
*/
void QIcon::detach()
{
if (d) {
if (d->engine->isNull()) {
if (!d->ref.deref())
delete d;
d = nullptr;
return;
} else if (d->ref.loadRelaxed() != 1) {
QIconPrivate *x = new QIconPrivate(d->engine->clone());
if (!d->ref.deref())
delete d;
d = x;
}