/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtWidgets 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 "qsizepolicy.h" #include #include #include QT_BEGIN_NAMESPACE /*! \class QSizePolicy \brief The QSizePolicy class is a layout attribute describing horizontal and vertical resizing policy. \ingroup geomanagement \inmodule QtWidgets The size policy of a widget is an expression of its willingness to be resized in various ways, and affects how the widget is treated by the \l{Layout Management}{layout engine}. Each widget returns a QSizePolicy that describes the horizontal and vertical resizing policy it prefers when being laid out. You can change this for a specific widget by changing its QWidget::sizePolicy property. QSizePolicy contains two independent QSizePolicy::Policy values and two stretch factors; one describes the widgets's horizontal size policy, and the other describes its vertical size policy. It also contains a flag to indicate whether the height and width of its preferred size are related. The horizontal and vertical policies can be set in the constructor, and altered using the setHorizontalPolicy() and setVerticalPolicy() functions. The stretch factors can be set using the setHorizontalStretch() and setVerticalStretch() functions. The flag indicating whether the widget's \l{QWidget::sizeHint()}{sizeHint()} is width-dependent (such as a menu bar or a word-wrapping label) can be set using the setHeightForWidth() function. The current size policies and stretch factors be retrieved using the horizontalPolicy(), verticalPolicy(), horizontalStretch() and verticalStretch() functions. Alternatively, use the transpose() function to swap the horizontal and vertical policies and stretches. The hasHeightForWidth() function returns the current status of the flag indicating the size hint dependencies. Use the expandingDirections() function to determine whether the associated widget can make use of more space than its \l{QWidget::sizeHint()}{sizeHint()} function indicates, as well as find out in which directions it can expand. Finally, the QSizePolicy class provides operators comparing this size policy to a given policy, as well as a QVariant operator storing this QSizePolicy as a QVariant object. \sa QSize, QWidget::sizeHint(), QWidget::sizePolicy, QLayoutItem::sizeHint() */ /*! \enum QSizePolicy::PolicyFlag These flags are combined together to form the various \l{Policy} values: \value GrowFlag The widget can grow beyond its size hint if necessary. \value ExpandFlag The widget should get as much space as possible. \value ShrinkFlag The widget can shrink below its size hint if necessary. \value IgnoreFlag The widget's size hint is ignored. The widget will get as much space as possible. \sa Policy */ /*! \enum QSizePolicy::Policy This enum describes the various per-dimension sizing types used when constructing a QSizePolicy. \value Fixed The QWidget::sizeHint() is the only acceptable alternative, so the widget can never grow or shrink (e.g. the vertical direction of a push button). \value Minimum The sizeHint() is minimal, and sufficient. The widget can be expanded, but there is no advantage to it being larger (e.g. the horizontal direction of a push button). It cannot be smaller than the size provided by sizeHint(). \value Maximum The sizeHint() is a maximum. The widget can be shrunk any amount without detriment if other widgets need the space (e.g. a separator line). It cannot be larger than the size provided by sizeHint(). \value Preferred The sizeHint() is best, but the widget can be shrunk and still be useful. The widget can be expanded, but there is no advantage to it being larger than sizeHint() (the default QWidget policy). \value Expanding The sizeHint() is a sensible size, but the widget can be shrunk and still be useful. The widget can make use of extra space, so it should get as much space as possible (e.g. the horizontal direction of a horizontal slider). \value MinimumExpanding The sizeHint() is minimal, and sufficient. The widget can make use of extra space, so it should get as much space as possible (e.g. the horizontal direction of a horizontal slider). \value Ignored The sizeHint() is ignored. The widget will get as much space as possible. \sa PolicyFlag, setHorizontalPolicy(), setVerticalPolicy() */ /*! \fn QSizePolicy::QSizePolicy() Constructs a QSizePolicy object with \l Fixed as its horizontal and vertical policies. The policies can be altered using the setHorizontalPolicy() and setVerticalPolicy() functions. Use the setHeightForWidth() function if the preferred height of the widget is dependent on the width of the widget (for example, a QLabel with line wrapping). \sa setHorizontalStretch(), setVerticalStretch() */ /*! \fn QSizePolicy::QSizePolicy(Policy horizontal, Policy vertical, ControlType type) \since 4.3 Constructs a QSizePolicy object with the given \a horizontal and \a vertical policies, and the specified control \a type. Use setHeightForWidth() if the preferred height of the widget is dependent on the width of the widget (for example, a QLabel with line wrapping). \sa setHorizontalStretch(), setVerticalStretch(), controlType() */ /*! \fn QSizePolicy::Policy QSizePolicy::horizontalPolicy() const Returns the horizontal component of the size policy. \sa setHorizontalPolicy(), verticalPolicy(), horizontalStretch() */ /*! \fn QSizePolicy::Policy QSizePolicy::verticalPolicy() const Returns the vertical component of the size policy. \sa setVerticalPolicy(), horizontalPolicy(), verticalStretch() */ /*! \fn void QSizePolicy::setHorizontalPolicy(Policy policy) Sets the horizontal component to the given \a policy. \sa horizontalPolicy(), setVerticalPolicy(), setHorizontalStretch() */ /*! \fn void QSizePolicy::setVerticalPolicy(Policy policy) Sets the vertical component to the given \a policy. \sa verticalPolicy(), setHorizontalPolicy(), setVerticalStretch() */ /*! \fn Qt::Orientations QSizePolicy::expandingDirections() const Returns whether a widget can make use of more space than the QWidget::sizeHint() function indicates. A value of Qt::Horizontal or Qt::Vertical means that the widget can grow horizontally or vertically (i.e., the horizontal or vertical policy is \l Expanding or \l MinimumExpanding), whereas Qt::Horizontal | Qt::Vertical means that it can grow in both dimensions. \sa horizontalPolicy(), verticalPolicy() */ /*! \since 4.3 Returns the control type associated with the widget for which this size policy applies. */ QSizePolicy::ControlType QSizePolicy::controlType() const Q_DECL_NOTHROW { return QSizePolicy::ControlType(1 << bits.ctype); } /*! \since 4.3 Sets the control type associated with the widget for which this size policy applies to \a type. The control type specifies the type of the widget for which this size policy applies. It is used by some styles, notably QMacStyle, to insert proper spacing between widgets. For example, the \macos Aqua guidelines specify that push buttons should be separated by 12 pixels, whereas vertically stacked radio buttons only require 6 pixels. \sa QStyle::layoutSpacing() */ void QSizePolicy::setControlType(ControlType type) Q_DECL_NOTHROW { bits.ctype = toControlTypeFieldValue(type); } /*! \fn void QSizePolicy::setHeightForWidth(bool dependent) Sets the flag determining whether the widget's preferred height depends on its width, to \a dependent. \sa hasHeightForWidth(), setWidthForHeight() */ /*! \fn bool QSizePolicy::hasHeightForWidth() const Returns \c true if the widget's preferred height depends on its width; otherwise returns \c false. \sa setHeightForWidth() */ /*! \fn void QSizePolicy::setWidthForHeight(bool dependent) Sets the flag determining whether the widget's width depends on its height, to \a dependent. This is only supported for QGraphicsLayout's subclasses. It is not possible to have a layout with both height-for-width and width-for-height constraints at the same time. \sa hasWidthForHeight(), setHeightForWidth() */ /*! \fn bool QSizePolicy::hasWidthForHeight() const Returns \c true if the widget's width depends on its height; otherwise returns \c false. \sa setWidthForHeight() */ /*! \fn bool QSizePolicy::operator==(const QSizePolicy &other) const Returns \c true if this policy is equal to \a other; otherwise returns \c false. \sa operator!=() */ /*! \fn bool QSizePolicy::operator!=(const QSizePolicy &other) const Returns \c true if this policy is different from \a other; otherwise returns \c false. \sa operator==() */ /*! \fn uint qHash(QSizePolicy key, uint seed = 0) \since 5.6 \relates QSizePolicy Returns the hash value for \a key, using \a seed to seed the calculation. */ /*! \fn int QSizePolicy::horizontalStretch() const Returns the horizontal stretch factor of the size policy. \sa setHorizontalStretch(), verticalStretch(), horizontalPolicy() */ /*! \fn int QSizePolicy::verticalStretch() const Returns the vertical stretch factor of the size policy. \sa setVerticalStretch(), horizontalStretch(), verticalPolicy() */ /*! \fn void QSizePolicy::setHorizontalStretch(int stretchFactor) Sets the horizontal stretch factor of the size policy to the given \a stretchFactor. \a stretchFactor must be in the range [0,255]. When two widgets are adjacent to each other in a horizontal layout, setting the horizontal stretch factor of the widget on the left to 2 and the factor of widget on the right to 1 will ensure that the widget on the left will always be twice the size of the one on the right. \sa horizontalStretch(), setVerticalStretch(), setHorizontalPolicy() */ /*! \fn void QSizePolicy::setVerticalStretch(int stretchFactor) Sets the vertical stretch factor of the size policy to the given \a stretchFactor. \a stretchFactor must be in the range [0,255]. When two widgets are adjacent to each other in a vertical layout, setting the vertical stretch factor of the widget on the top to 2 and the factor of widget on the bottom to 1 will ensure that the widget on the top will always be twice the size of the one on the bottom. \sa verticalStretch(), setHorizontalStretch(), setVerticalPolicy() */ /*! \fn void QSizePolicy::transpose() Swaps the horizontal and vertical policies and stretches. \sa transposed() */ /*! \fn QSizePolicy QSizePolicy::transposed() const \since 5.9 Returns a size policy object with the horizontal and vertical policies and stretches swapped. \sa transpose() */ /*! \fn void QSizePolicy::retainSizeWhenHidden() const \since 5.2 Returns whether the layout should retain the widget's size when it is hidden. This is \c false by default. \sa setRetainSizeWhenHidden() */ /*! \fn void QSizePolicy::setRetainSizeWhenHidden(bool retainSize) \since 5.2 Sets whether a layout should retain the widget's size when it is hidden. If \a retainSize is \c true, the layout will not be changed by hiding the widget. \sa retainSizeWhenHidden() */ /*! \enum QSizePolicy::ControlType \since 4.3 This enum specifies the different types of widgets in terms of layout interaction: \value DefaultType The default type, when none is specified. \value ButtonBox A QDialogButtonBox instance. \value CheckBox A QCheckBox instance. \value ComboBox A QComboBox instance. \value Frame A QFrame instance. \value GroupBox A QGroupBox instance. \value Label A QLabel instance. \value Line A QFrame instance with QFrame::HLine or QFrame::VLine. \value LineEdit A QLineEdit instance. \value PushButton A QPushButton instance. \value RadioButton A QRadioButton instance. \value Slider A QAbstractSlider instance. \value SpinBox A QAbstractSpinBox instance. \value TabWidget A QTabWidget instance. \value ToolButton A QToolButton instance. \sa setControlType(), controlType() */ /*! Returns a QVariant storing this QSizePolicy. */ QSizePolicy::operator QVariant() const { return QVariant(QVariant::SizePolicy, this); } #ifndef QT_NO_DATASTREAM /*! \relates QSizePolicy \since 4.2 Writes the size \a policy to the data stream \a stream. \sa{Serializing Qt Data Types}{Format of the QDataStream operators} */ QDataStream &operator<<(QDataStream &stream, const QSizePolicy &policy) { // The order here is for historical reasons. (compatibility with Qt4) quint32 data = (policy.bits.horPolicy | // [0, 3] policy.bits.verPolicy << 4 | // [4, 7] policy.bits.hfw << 8 | // [8] policy.bits.ctype << 9 | // [9, 13] policy.bits.wfh << 14 | // [14] policy.bits.retainSizeWhenHidden << 15 | // [15] policy.bits.verStretch << 16 | // [16, 23] policy.bits.horStretch << 24); // [24, 31] return stream << data; } #define VALUE_OF_BITS(data, bitstart, bitcount) ((data >> bitstart) & ((1 << bitcount) -1)) /*! \relates QSizePolicy \since 4.2 Reads the size \a policy from the data stream \a stream. \sa{Serializing Qt Data Types}{Format of the QDataStream operators} */ QDataStream &operator>>(QDataStream &stream, QSizePolicy &policy) { quint32 data; stream >> data; policy.bits.horPolicy = VALUE_OF_BITS(data, 0, 4); policy.bits.verPolicy = VALUE_OF_BITS(data, 4, 4); policy.bits.hfw = VALUE_OF_BITS(data, 8, 1); policy.bits.ctype = VALUE_OF_BITS(data, 9, 5); policy.bits.wfh = VALUE_OF_BITS(data, 14, 1); policy.bits.retainSizeWhenHidden = VALUE_OF_BITS(data, 15, 1); policy.bits.verStretch = VALUE_OF_BITS(data, 16, 8); policy.bits.horStretch = VALUE_OF_BITS(data, 24, 8); return stream; } #endif // QT_NO_DATASTREAM #ifndef QT_NO_DEBUG_STREAM QDebug operator<<(QDebug dbg, const QSizePolicy &p) { QDebugStateSaver saver(dbg); dbg.nospace() << "QSizePolicy(horizontalPolicy = " << p.horizontalPolicy() << ", verticalPolicy = " << p.verticalPolicy() << ')'; return dbg; } #endif QT_END_NAMESPACE #include "moc_qsizepolicy.cpp"