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#include "qlayout.h"

#include "qapplication.h"

#include "qlayoutengine_p.h"

#include "qmenubar.h"

#include "qtoolbar.h"

#include "qevent.h"

#include "qstyle.h"

#include "qvariant.h"

#include "qwidget_p.h"

QT_BEGIN_NAMESPACE

inline static QRect fromLayoutItemRect(QWidgetPrivate *priv, const QRect &rect)

{

    return rect.adjusted(priv->leftLayoutItemMargin, priv->topLayoutItemMargin,

                         -priv->rightLayoutItemMargin, -priv->bottomLayoutItemMargin);

}

inline static QSize fromLayoutItemSize(QWidgetPrivate *priv, const QSize &size)

{

    return fromLayoutItemRect(priv, QRect(QPoint(0, 0), size)).size();

}

inline static QRect toLayoutItemRect(QWidgetPrivate *priv, const QRect &rect)

{

    return rect.adjusted(-priv->leftLayoutItemMargin, -priv->topLayoutItemMargin,

                         priv->rightLayoutItemMargin, priv->bottomLayoutItemMargin);

}

inline static QSize toLayoutItemSize(QWidgetPrivate *priv, const QSize &size)

{

    return toLayoutItemRect(priv, QRect(QPoint(0, 0), size)).size();

}

/*!

   Returns a QVariant storing this QSizePolicy.

*/

QSizePolicy::operator QVariant() const

{

    return QVariant(QVariant::SizePolicy, this);

}

/*!

    \class QLayoutItem

    \brief The QLayoutItem class provides an abstract item that a

    QLayout manipulates.

    \ingroup geomanagement

    This is used by custom layouts.

    Pure virtual functions are provided to return information about

    the layout, including, sizeHint(), minimumSize(), maximumSize()

    and expanding().

    The layout's geometry can be set and retrieved with setGeometry()

    and geometry(), and its alignment with setAlignment() and

    alignment().

    isEmpty() returns whether the layout item is empty. If the

    concrete item is a QWidget, it can be retrieved using widget().

    Similarly for layout() and spacerItem().

    Some layouts have width and height interdependencies. These can

    be expressed using hasHeightForWidth(), heightForWidth(), and

    minimumHeightForWidth(). For more explanation see the \e{Qt

    Quarterly} article

    \l{http://qt.nokia.com/doc/qq/qq04-height-for-width.html}{Trading

    Height for Width}.

    \sa QLayout

*/

/*!

    \class QSpacerItem

    \ingroup geomanagement

    \brief The QSpacerItem class provides blank space in a layout.

    Normally, you don't need to use this class directly. Qt's

    built-in layout managers provide the following functions for

    manipulating empty space in layouts:

    \table

    \header \o Class

            \o Functions

    \row    \o QHBoxLayout

            \o \l{QBoxLayout::addSpacing()}{addSpacing()},

               \l{QBoxLayout::addStretch()}{addStretch()},

               \l{QBoxLayout::insertSpacing()}{insertSpacing()},

               \l{QBoxLayout::insertStretch()}{insertStretch()}

    \row    \o QGridLayout

            \o \l{QGridLayout::setRowMinimumHeight()}{setRowMinimumHeight()},

               \l{QGridLayout::setRowStretch()}{setRowStretch()},

               \l{QGridLayout::setColumnMinimumWidth()}{setColumnMinimumWidth()},

               \l{QGridLayout::setColumnStretch()}{setColumnStretch()}

    \endtable

    \sa QLayout, QWidgetItem, QLayoutItem::spacerItem()

*/

/*!

    \class QWidgetItem

    \ingroup geomanagement

    \brief The QWidgetItem class is a layout item that represents a widget.

    Normally, you don't need to use this class directly. Qt's

    built-in layout managers provide the following functions for

    manipulating widgets in layouts:

    \table

    \header \o Class

            \o Functions

    \row    \o QBoxLayout

            \o \l{QBoxLayout::addWidget()}{addWidget()},

               \l{QBoxLayout::insertWidget()}{insertWidget()},

               \l{QBoxLayout::setStretchFactor()}{setStretchFactor()}

    \row    \o QGridLayout

            \o \l{QGridLayout::addWidget()}{addWidget()}

    \row    \o QStackedLayout

            \o \l{QStackedLayout::addWidget()}{addWidget()},

               \l{QStackedLayout::insertWidget()}{insertWidget()},

               \l{QStackedLayout::currentWidget()}{currentWidget()},

               \l{QStackedLayout::setCurrentWidget()}{setCurrentWidget()},

               \l{QStackedLayout::widget()}{widget()}

    \endtable

    \sa QLayout, QSpacerItem, QLayoutItem::widget()

*/

/*!

    \fn QLayoutItem::QLayoutItem(Qt::Alignment alignment)

    Constructs a layout item with an \a alignment.

    Not all subclasses support alignment.

*/

/*!

    \fn Qt::Alignment QLayoutItem::alignment() const

    Returns the alignment of this item.

*/

/*!

    Sets the alignment of this item to \a alignment.

    \bold{Note:} Item alignment is only supported by QLayoutItem subclasses

    where it would have a visual effect. Except for QSpacerItem, which provides

    blank space for layouts, all public Qt classes that inherit QLayoutItem

    support item alignment.

*/

void QLayoutItem::setAlignment(Qt::Alignment alignment)

{

    align = alignment;

}

/*!

    \fn QSize QLayoutItem::maximumSize() const

    Implemented in subclasses to return the maximum size of this item.

*/

/*!

    \fn QSize QLayoutItem::minimumSize() const

    Implemented in subclasses to return the minimum size of this item.

*/

/*!

    \fn QSize QLayoutItem::sizeHint() const

    Implemented in subclasses to return the preferred size of this item.

*/

/*!

    \fn Qt::Orientations QLayoutItem::expandingDirections() const

    Returns whether this layout item can make use of more space than

    sizeHint(). A value of Qt::Vertical or Qt::Horizontal means that

    it wants to grow in only one dimension, whereas Qt::Vertical |

    Qt::Horizontal means that it wants to grow in both dimensions.

*/

/*!

    \fn void QLayoutItem::setGeometry(const QRect &r)

    Implemented in subclasses to set this item's geometry to \a r.

    \sa geometry()

*/

/*!

    \fn QRect QLayoutItem::geometry() const

    Returns the rectangle covered by this layout item.

    \sa setGeometry()

*/

/*!

    \fn virtual bool QLayoutItem::isEmpty() const

    Implemented in subclasses to return whether this item is empty,

    i.e. whether it contains any widgets.

*/

/*!

    \fn QSpacerItem::QSpacerItem(int w, int h, QSizePolicy::Policy hPolicy, QSizePolicy::Policy vPolicy)

    Constructs a spacer item with preferred width \a w, preferred

    height \a h, horizontal size policy \a hPolicy and vertical size

    policy \a vPolicy.

    The default values provide a gap that is able to stretch if

    nothing else wants the space.

*/

/*!

    Changes this spacer item to have preferred width \a w, preferred

    height \a h, horizontal size policy \a hPolicy and vertical size

    policy \a vPolicy.

    The default values provide a gap that is able to stretch if

    nothing else wants the space.

    Note that if changeSize() is called after the spacer item has been added

    to a layout, it is necessary to invalidate the layout in order for the

    spacer item's new size to take effect.

    \sa QSpacerItem::invalidate()

*/

void QSpacerItem::changeSize(int w, int h, QSizePolicy::Policy hPolicy,

                             QSizePolicy::Policy vPolicy)

{

    width = w;

    height = h;

    sizeP = QSizePolicy(hPolicy, vPolicy);

}

/*!

    \fn QWidgetItem::QWidgetItem(QWidget *widget)

    Creates an item containing the given \a widget.

*/

/*!

    Destroys the QLayoutItem.

*/

QLayoutItem::~QLayoutItem()

{

}

/*!

    Invalidates any cached information in this layout item.

*/

void QLayoutItem::invalidate()

{

}

/*!

    If this item is a QLayout, it is returned as a QLayout; otherwise

    0 is returned. This function provides type-safe casting.

*/

QLayout * QLayoutItem::layout()

{

    return 0;

}

/*!

    If this item is a QSpacerItem, it is returned as a QSpacerItem;

    otherwise 0 is returned. This function provides type-safe casting.

*/

QSpacerItem * QLayoutItem::spacerItem()

{

    return 0;

}

/*!

    \reimp

*/

QLayout * QLayout::layout()

{

    return this;

}

/*!

    Returns a pointer to this object.

*/

QSpacerItem * QSpacerItem::spacerItem()

{

    return this;

}

/*!

    If this item is a QWidget, it is returned as a QWidget; otherwise

    0 is returned. This function provides type-safe casting.

*/

QWidget * QLayoutItem::widget()

{

    return 0;

}

/*!

    Returns the widget managed by this item.

*/

QWidget *QWidgetItem::widget()

{

    return wid;

}

/*!

    Returns true if this layout's preferred height depends on its

    width; otherwise returns false. The default implementation returns

    false.

    Reimplement this function in layout managers that support height

    for width.

    \sa heightForWidth(), QWidget::heightForWidth()

*/

bool QLayoutItem::hasHeightForWidth() const

{

    return false;

}

/*!

    Returns the minimum height this widget needs for the given width,

    \a w. The default implementation simply returns heightForWidth(\a

    w).

*/

int QLayoutItem::minimumHeightForWidth(int w) const

{

    return heightForWidth(w);

}

/*!

    Returns the preferred height for this layout item, given the width

    \a w.

    The default implementation returns -1, indicating that the

    preferred height is independent of the width of the item. Using

    the function hasHeightForWidth() will typically be much faster

    than calling this function and testing for -1.

    Reimplement this function in layout managers that support height

    for width. A typical implementation will look like this:

    \snippet doc/src/snippets/code/src_gui_kernel_qlayoutitem.cpp 0

    Caching is strongly recommended; without it layout will take

    exponential time.

    \sa hasHeightForWidth()

*/

int QLayoutItem::heightForWidth(int /* w */) const

{

    return -1;

}

/*!

    Returns the control type(s) for the layout item. For a

    QWidgetItem, the control type comes from the widget's size

    policy; for a QLayoutItem, the control types is derived from the

    layout's contents.

    \sa QSizePolicy::controlType()

*/

QSizePolicy::ControlTypes QLayoutItem::controlTypes() const

{

    // ### Qt 5: This function should probably be virtual instead

    if (const QWidget *widget = const_cast<QLayoutItem*>(this)->widget()) {

        return widget->sizePolicy().controlType();

    } else if (const QLayout *layout = const_cast<QLayoutItem*>(this)->layout()) {

        if (layout->count() == 0)

            return QSizePolicy::DefaultType;

        QSizePolicy::ControlTypes types;

        for (int i = layout->count() - 1; i >= 0; --i)

            types |= layout->itemAt(i)->controlTypes();

        return types;

    }

    return QSizePolicy::DefaultType;

}

/*!

    \reimp

*/

void QSpacerItem::setGeometry(const QRect &r)

{

    rect = r;

}

/*!

    \reimp

*/

void QWidgetItem::setGeometry(const QRect &rect)

{

    if (isEmpty())

        return;

    QRect r = !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)

            ? fromLayoutItemRect(wid->d_func(), rect)

            : rect;

    const QSize widgetRectSurplus = r.size() - rect.size(); 

    /* 

       For historical reasons, this code is done using widget rect 

       coordinates, not layout item rect coordinates. However, 

       QWidgetItem's sizeHint(), maximumSize(), and heightForWidth() 

       all work in terms of layout item rect coordinates, so we have to 

       add or subtract widgetRectSurplus here and there. The code could 

       be much simpler if we did everything using layout item rect 

       coordinates and did the conversion right before the call to 

       QWidget::setGeometry(). 

     */ 

    QSize s = r.size().boundedTo(maximumSize() + widgetRectSurplus);  

    int x = r.x();

    int y = r.y();

    if (align & (Qt::AlignHorizontal_Mask | Qt::AlignVertical_Mask)) {

        QSize pref(sizeHint());

        QSizePolicy sp = wid->sizePolicy();

        if (sp.horizontalPolicy() == QSizePolicy::Ignored)

            pref.setWidth(wid->sizeHint().expandedTo(wid->minimumSize()).width());

        if (sp.verticalPolicy() == QSizePolicy::Ignored)

            pref.setHeight(wid->sizeHint().expandedTo(wid->minimumSize()).height());

        pref += widgetRectSurplus;

        if (align & Qt::AlignHorizontal_Mask)

            s.setWidth(qMin(s.width(), pref.width()));

        if (align & Qt::AlignVertical_Mask) {

            if (hasHeightForWidth())

                s.setHeight(qMin(s.height(), 

                                 heightForWidth(s.width() - widgetRectSurplus.width()) 

                                 + widgetRectSurplus.height()));

            else

                s.setHeight(qMin(s.height(), pref.height()));

        }

    }

    Qt::Alignment alignHoriz = QStyle::visualAlignment(wid->layoutDirection(), align);

    if (alignHoriz & Qt::AlignRight)

        x = x + (r.width() - s.width());

    else if (!(alignHoriz & Qt::AlignLeft))

        x = x + (r.width() - s.width()) / 2;

    if (align & Qt::AlignBottom)

        y = y + (r.height() - s.height());

    else if (!(align & Qt::AlignTop))

        y = y + (r.height() - s.height()) / 2;

    wid->setGeometry(x, y, s.width(), s.height());

}

/*!

    \reimp

*/

QRect QSpacerItem::geometry() const

{

    return rect;

}

/*!

    \reimp

*/

QRect QWidgetItem::geometry() const

{

    return !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)

           ? toLayoutItemRect(wid->d_func(), wid->geometry())

           : wid->geometry();

}

/*!

    \reimp

*/

bool QWidgetItem::hasHeightForWidth() const

{

    if (isEmpty())

        return false;

    if (wid->layout())

        return wid->layout()->hasHeightForWidth();

    return wid->sizePolicy().hasHeightForWidth();

}

/*!

    \reimp

*/

int QWidgetItem::heightForWidth(int w) const

{