QWidgetItemV2 Class Reference

#include <qlayoutitem.h>

Inheritance diagram for QWidgetItemV2:

Public Functions
int	heightForWidth (int width) const
	Reimplemented Function More...
QSize	maximumSize () const
	Reimplemented Function More...
QSize	minimumSize () const
	Reimplemented Function More...
	QWidgetItemV2 (QWidget *widget)
QSize	sizeHint () const
	Reimplemented Function More...
	~QWidgetItemV2 ()
Public Functions inherited from QWidgetItem
Qt::Orientations	expandingDirections () const
	Reimplemented Function More...
QRect	geometry () const
	Reimplemented Function More...
bool	hasHeightForWidth () const
	Reimplemented Function More...
bool	isEmpty () const
	Returns true if the widget is hidden; otherwise returns false. More...
	QWidgetItem (QWidget *w)
	Creates an item containing the given widget. More...
void	setGeometry (const QRect &)
	Reimplemented Function More...
virtual QWidget *	widget ()
	Returns the widget managed by this item. More...
Public Functions inherited from QLayoutItem
Qt::Alignment	alignment () const
	Returns the alignment of this item. More...
QSizePolicy::ControlTypes	controlTypes () const
	Returns the control type(s) for the layout item. More...
virtual void	invalidate ()
	Invalidates any cached information in this layout item. More...
virtual QLayout *	layout ()
	If this item is a QLayout, it is returned as a QLayout; otherwise 0 is returned. More...
virtual int	minimumHeightForWidth (int) const
	Returns the minimum height this widget needs for the given width, w. More...
	QLayoutItem (Qt::Alignment alignment=0)
	Constructs a layout item with an alignment. More...
void	setAlignment (Qt::Alignment a)
	Sets the alignment of this item to alignment. More...
virtual QSpacerItem *	spacerItem ()
	If this item is a QSpacerItem, it is returned as a QSpacerItem; otherwise 0 is returned. More...
virtual	~QLayoutItem ()
	Destroys the QLayoutItem. More...

Private Types
enum	{ Dirty = -123, HfwCacheMaxSize = 3 }

Private Functions
void	invalidateSizeCache ()
void	updateCacheIfNecessary () const
bool	useSizeCache () const

Properties
void *	d
QSize	q_cachedHfws [HfwCacheMaxSize]
QSize	q_cachedMaximumSize
QSize	q_cachedMinimumSize
QSize	q_cachedSizeHint
short	q_firstCachedHfw
short	q_hfwCacheSize

Friends
class	QWidgetPrivate

Additional Inherited Members
Protected Variables inherited from QWidgetItem
QWidget *	wid
Protected Variables inherited from QLayoutItem
Qt::Alignment	align

Detailed Description

Warning

This function is not part of the public interface.

Definition at line 144 of file qlayoutitem.h.

Enumerations

anonymous enum

anonymous enum

private

Enumerator
Dirty
HfwCacheMaxSize

Definition at line 156 of file qlayoutitem.h.

{ Dirty = -123, HfwCacheMaxSize = 3 };

Constructors and Destructors

QWidgetItemV2()

QWidgetItemV2::QWidgetItemV2 ( QWidget *  widget )

explicit

Definition at line 771 of file qlayoutitem.cpp.

    : QWidgetItem(widget),
      q_cachedMinimumSize(Dirty, Dirty),
      q_cachedSizeHint(Dirty, Dirty),
      q_cachedMaximumSize(Dirty, Dirty),
      q_firstCachedHfw(0),
      q_hfwCacheSize(0),
      d(0)
{
    QWidgetPrivate *wd = wid->d_func();
    if (!wd->widgetItem)
        wd->widgetItem = this;
}

~QWidgetItemV2()

QWidgetItemV2::~QWidgetItemV2

(

)

Definition at line 785 of file qlayoutitem.cpp.

{
    if (wid) {
        QWidgetPrivate *wd = wid->d_func();
        if (wd->widgetItem == this)
            wd->widgetItem = 0;
    }
}

Functions

heightForWidth()

int QWidgetItemV2::heightForWidth ( int  w ) const

virtual

Reimplemented Function

Reimplemented from QWidgetItem.

Definition at line 848 of file qlayoutitem.cpp.

{
    if (isEmpty())
        return -1;

    for (int i = 0; i < q_hfwCacheSize; ++i) {
        int offset = q_firstCachedHfw + i;
        const QSize &size = q_cachedHfws[offset % HfwCacheMaxSize];
        if (size.width() == width) {
            if (q_hfwCacheSize == HfwCacheMaxSize)
                q_firstCachedHfw = offset;
            return size.height();
        }
    }

    if (q_hfwCacheSize < HfwCacheMaxSize)
        ++q_hfwCacheSize;
    q_firstCachedHfw = (q_firstCachedHfw + HfwCacheMaxSize - 1) % HfwCacheMaxSize;

    int height = QWidgetItem::heightForWidth(width);
    q_cachedHfws[q_firstCachedHfw] = QSize(width, height);
    return height;
}

invalidateSizeCache()

void QWidgetItemV2::invalidateSizeCache ( )

inlineprivate

Definition at line 160 of file qlayoutitem.h.

                                      {
        q_cachedMinimumSize.setWidth(Dirty);
        q_hfwCacheSize = 0;
    }

maximumSize()

QSize QWidgetItemV2::maximumSize ( ) const

virtual

Reimplemented Function

Reimplemented from QWidgetItem.

Definition at line 820 of file qlayoutitem.cpp.

{
    if (isEmpty())
        return QSize(0, 0);

    if (useSizeCache()) {
        updateCacheIfNecessary();
        return q_cachedMaximumSize;
    } else {
        return QWidgetItem::maximumSize();
    }
}

minimumSize()

QSize QWidgetItemV2::minimumSize ( ) const

virtual

Reimplemented Function

Reimplemented from QWidgetItem.

Definition at line 807 of file qlayoutitem.cpp.

{
    if (isEmpty())
        return QSize(0, 0);

    if (useSizeCache()) {
        updateCacheIfNecessary();
        return q_cachedMinimumSize;
    } else {
        return QWidgetItem::minimumSize();
    }
}

sizeHint()

QSize QWidgetItemV2::sizeHint ( ) const

virtual

Reimplemented Function

Reimplemented from QWidgetItem.

Definition at line 794 of file qlayoutitem.cpp.

{
    if (isEmpty())
        return QSize(0, 0);

    if (useSizeCache()) {
        updateCacheIfNecessary();
        return q_cachedSizeHint;
    } else {
        return QWidgetItem::sizeHint();
    }
}

updateCacheIfNecessary()

void QWidgetItemV2::updateCacheIfNecessary ( ) const

private

Definition at line 733 of file qlayoutitem.cpp.

Referenced by maximumSize(), minimumSize(), and sizeHint().

{
    if (q_cachedMinimumSize.width() != Dirty)
        return;

    const QSize sizeHint(wid->sizeHint());
    const QSize minimumSizeHint(wid->minimumSizeHint());
    const QSize minimumSize(wid->minimumSize());
    const QSize maximumSize(wid->maximumSize());
    const QSizePolicy sizePolicy(wid->sizePolicy());
    const QSize expandedSizeHint(sizeHint.expandedTo(minimumSizeHint));

    const QSize smartMinSize(qSmartMinSize(sizeHint, minimumSizeHint, minimumSize, maximumSize, sizePolicy));
    const QSize smartMaxSize(qSmartMaxSize(expandedSizeHint, minimumSize, maximumSize, sizePolicy, align));

    const bool useLayoutItemRect = !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect);

    q_cachedMinimumSize = useLayoutItemRect
           ? toLayoutItemSize(wid->d_func(), smartMinSize)
           : smartMinSize;

    q_cachedSizeHint = expandedSizeHint;
    q_cachedSizeHint = q_cachedSizeHint.boundedTo(maximumSize)
                                       .expandedTo(minimumSize);
    q_cachedSizeHint = useLayoutItemRect
           ? toLayoutItemSize(wid->d_func(), q_cachedSizeHint)
           : q_cachedSizeHint;

    if (wid->sizePolicy().horizontalPolicy() == QSizePolicy::Ignored)
        q_cachedSizeHint.setWidth(0);
    if (wid->sizePolicy().verticalPolicy() == QSizePolicy::Ignored)
        q_cachedSizeHint.setHeight(0);

    q_cachedMaximumSize = useLayoutItemRect
               ? toLayoutItemSize(wid->d_func(), smartMaxSize)
               : smartMaxSize;
}

useSizeCache()

bool QWidgetItemV2::useSizeCache ( ) const

inlineprivate

Definition at line 728 of file qlayoutitem.cpp.

Referenced by maximumSize(), minimumSize(), and sizeHint().

{
    return wid->d_func()->widgetItem == this;
}

Friends and Related Functions

QWidgetPrivate

friend class QWidgetPrivate

friend

Definition at line 173 of file qlayoutitem.h.

Properties

d

void* QWidgetItemV2::d

private

Definition at line 171 of file qlayoutitem.h.

q_cachedHfws

QSize QWidgetItemV2::q_cachedHfws[HfwCacheMaxSize]

mutableprivate

Definition at line 168 of file qlayoutitem.h.

Referenced by heightForWidth().

q_cachedMaximumSize

QSize QWidgetItemV2::q_cachedMaximumSize

mutableprivate

Definition at line 167 of file qlayoutitem.h.

Referenced by maximumSize().

q_cachedMinimumSize

QSize QWidgetItemV2::q_cachedMinimumSize

mutableprivate

Definition at line 165 of file qlayoutitem.h.

Referenced by minimumSize().

q_cachedSizeHint

QSize QWidgetItemV2::q_cachedSizeHint

mutableprivate

Definition at line 166 of file qlayoutitem.h.

Referenced by sizeHint().

q_firstCachedHfw

short QWidgetItemV2::q_firstCachedHfw

mutableprivate

Definition at line 169 of file qlayoutitem.h.

Referenced by heightForWidth().

q_hfwCacheSize

short QWidgetItemV2::q_hfwCacheSize

mutableprivate

Definition at line 170 of file qlayoutitem.h.

Referenced by heightForWidth().

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The documentation for this class was generated from the following files:

• /src/gui/kernel/qlayoutitem.h
• /src/gui/kernel/qlayoutitem.cpp