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Please review the following information to ensure ** the GNU Free Documentation License version 1.3 requirements ** will be met: http://www.gnu.org/copyleft/fdl.html. ** $QT_END_LICENSE$ ** ****************************************************************************/ /*! \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() */ /*! \fn ControlType QSizePolicy::controlType() const \since 4.3 Returns the control type associated with the widget for which this size policy applies. */ /*! \fn void QSizePolicy::setControlType(ControlType type) \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 Mac OS X Aqua guidelines specify that push buttons should be separated by 12 pixels, whereas vertically stacked radio buttons only require 6 pixels. \sa QStyle::layoutSpacing() */ /*! \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 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. */ /*! \fn void QSizePolicy::retainSizeWhenHidden() const \since 5.2 Returns if the layout should retain the widgets size when it is hidden. This is by default false. \sa setRetainSizeWhenHidden() */ /*! \fn void QSizePolicy::setRetainSizeWhenHidden(bool retainSize) \since 5.2 Set if a layout should retain the widgets size when it is hidden. If \a retainSize is 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() */