QWidgetItem Class Reference

The QWidgetItem class is a layout item that represents a widget. More...

#include <qlayoutitem.h>

Inheritance diagram for QWidgetItem:

Public Functions
Qt::Orientations	expandingDirections () const
	Reimplemented Function More...
QRect	geometry () const
	Reimplemented Function More...
bool	hasHeightForWidth () const
	Reimplemented Function More...
int	heightForWidth (int) const
	Reimplemented Function More...
bool	isEmpty () const
	Returns true if the widget is hidden; otherwise returns false. More...
QSize	maximumSize () const
	Reimplemented Function More...
QSize	minimumSize () const
	Reimplemented Function More...
	QWidgetItem (QWidget *w)
	Creates an item containing the given widget. More...
void	setGeometry (const QRect &)
	Reimplemented Function More...
QSize	sizeHint () const
	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...

Protected Variables
QWidget *	wid
Protected Variables inherited from QLayoutItem
Qt::Alignment	align

Detailed Description

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:

Class	Functions
QBoxLayout	addWidget(), insertWidget(), setStretchFactor()
QGridLayout	addWidget()
QStackedLayout	addWidget(), insertWidget(), currentWidget(), setCurrentWidget(), widget()

See also

QLayout, QSpacerItem, QLayoutItem::widget()

Definition at line 122 of file qlayoutitem.h.

Constructors and Destructors

QWidgetItem()

QWidgetItem::QWidgetItem ( QWidget *  w )

inlineexplicit

Creates an item containing the given widget.

Definition at line 127 of file qlayoutitem.h.

: wid(w) { }

Functions

expandingDirections()

Qt::Orientations QWidgetItem::expandingDirections ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 603 of file qlayoutitem.cpp.

Referenced by QToolBarLayout::updateGeomArray().

{
    if (isEmpty())
        return Qt::Orientations(0);

    Qt::Orientations e = wid->sizePolicy().expandingDirections();
    /*
      ### Qt 4.0:
      If the layout is expanding, we make the widget expanding, even if
      its own size policy isn't expanding. This behavior should be
      reconsidered.
    */
    if (wid->layout()) {
        if (wid->sizePolicy().horizontalPolicy() & QSizePolicy::GrowFlag
                && (wid->layout()->expandingDirections() & Qt::Horizontal))
            e |= Qt::Horizontal;
        if (wid->sizePolicy().verticalPolicy() & QSizePolicy::GrowFlag
                && (wid->layout()->expandingDirections() & Qt::Vertical))
            e |= Qt::Vertical;
    }

    if (align & Qt::AlignHorizontal_Mask)
        e &= ~Qt::Horizontal;
    if (align & Qt::AlignVertical_Mask)
        e &= ~Qt::Vertical;
    return e;
}

geometry()

QRect QWidgetItem::geometry ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 542 of file qlayoutitem.cpp.

Referenced by QPushButtonPrivate::adjustedMenuPosition().

{
    return !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
           ? toLayoutItemRect(wid->d_func(), wid->geometry())
           : wid->geometry();
}

hasHeightForWidth()

bool QWidgetItem::hasHeightForWidth ( ) const

virtual

Reimplemented Function

Reimplemented from QLayoutItem.

Definition at line 553 of file qlayoutitem.cpp.

{
    if (isEmpty())
        return false;
    return wid->d_func()->hasHeightForWidth();
}

heightForWidth()

int QWidgetItem::heightForWidth ( int  w ) const

virtual

Reimplemented Function

Reimplemented from QLayoutItem.

Reimplemented in QWidgetItemV2.

Definition at line 563 of file qlayoutitem.cpp.

Referenced by QWidgetItemV2::heightForWidth().

{
    if (isEmpty())
        return -1;

    w = !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
      ? fromLayoutItemSize(wid->d_func(), QSize(w, 0)).width()
      : w;

    int hfw;
    if (wid->layout())
        hfw = wid->layout()->totalHeightForWidth(w);
    else
        hfw = wid->heightForWidth(w);

    if (hfw > wid->maximumHeight())
        hfw = wid->maximumHeight();
    if (hfw < wid->minimumHeight())
        hfw = wid->minimumHeight();

    hfw = !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
        ? toLayoutItemSize(wid->d_func(), QSize(0, hfw)).height()
        : hfw;

    if (hfw < 0)
        hfw = 0;
    return hfw;
}

isEmpty()

bool QWidgetItem::isEmpty ( ) const

virtual

Returns true if the widget is hidden; otherwise returns false.

See also

QWidget::isHidden()

Implements QLayoutItem.

Reimplemented in QToolBarItem.

Definition at line 718 of file qlayoutitem.cpp.

Referenced by QWidgetItemV2::heightForWidth(), QWidgetItemV2::maximumSize(), QWidgetItemV2::minimumSize(), and QWidgetItemV2::sizeHint().

{
    return wid->isHidden() || wid->isWindow();
}

maximumSize()

QSize QWidgetItem::maximumSize ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Reimplemented in QDockWidgetItem, and QWidgetItemV2.

Definition at line 664 of file qlayoutitem.cpp.

Referenced by QMainWindowLayout::fixSizeInUnifiedToolbar(), make_widget_eventUPP(), QWidgetItemV2::maximumSize(), and QToolBarLayout::updateGeomArray().

{
    if (isEmpty()) {
        return QSize(0, 0);
    } else {
        return !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
               ? toLayoutItemSize(wid->d_func(), qSmartMaxSize(this, align))
               : qSmartMaxSize(this, align);
    }
}

minimumSize()

QSize QWidgetItem::minimumSize ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Reimplemented in QDockWidgetItem, and QWidgetItemV2.

Definition at line 643 of file qlayoutitem.cpp.

Referenced by QMainWindowLayout::fixSizeInUnifiedToolbar(), make_widget_eventUPP(), QWidgetItemV2::minimumSize(), and QToolBarLayout::updateGeomArray().

{
    if (isEmpty())
        return QSize(0, 0);
    return !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
           ? toLayoutItemSize(wid->d_func(), qSmartMinSize(this))
           : qSmartMinSize(this);
}

setGeometry()

void QWidgetItem::setGeometry ( const QRect &  rect )

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 474 of file qlayoutitem.cpp.

Referenced by QToolBarLayout::layoutActions().

{
    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());
}

sizeHint()

QSize QWidgetItem::sizeHint ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Reimplemented in QDockWidgetItem, and QWidgetItemV2.

Definition at line 686 of file qlayoutitem.cpp.

Referenced by QToolBarLayout::expandedSize(), QToolBarLayout::layoutActions(), QWidgetItemV2::sizeHint(), QDockWidgetItem::sizeHint(), and QToolBarLayout::updateGeomArray().

{
    QSize s(0, 0);
    if (!isEmpty()) {
        s = wid->sizeHint().expandedTo(wid->minimumSizeHint());
        s = s.boundedTo(wid->maximumSize())
             .expandedTo(wid->minimumSize());
        s = !wid->testAttribute(Qt::WA_LayoutUsesWidgetRect)
           ? toLayoutItemSize(wid->d_func(), s)
           : s;

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

widget()

QWidget * QWidgetItem::widget ( )

virtual

Returns the widget managed by this item.

Reimplemented from QLayoutItem.

Definition at line 385 of file qlayoutitem.cpp.

Referenced by defaultWidgetAction(), QToolBarLayout::layoutActions(), QToolBarLayout::takeAt(), QToolBarLayout::updateGeomArray(), and QToolBarLayout::~QToolBarLayout().

{
    return wid;
}

Properties

wid

QWidget* QWidgetItem::wid

protected

Definition at line 141 of file qlayoutitem.h.

Referenced by QWidgetItemV2::QWidgetItemV2(), QWidgetItemV2::~QWidgetItemV2(), and QWidgetPrivate::~QWidgetPrivate().

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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