source: trunk/src/gui/kernel/qstackedlayout.cpp@ 99

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#include "qstackedlayout.h"
#include "qlayout_p.h"

#include <qlist.h>
#include <qwidget.h>
#include "private/qlayoutengine_p.h"

QT_BEGIN_NAMESPACE

class QStackedLayoutPrivate : public QLayoutPrivate
{
    Q_DECLARE_PUBLIC(QStackedLayout)
public:
    QStackedLayoutPrivate() : index(-1), stackingMode(QStackedLayout::StackOne) {}
    QList<QLayoutItem *> list;
    int index;
    QStackedLayout::StackingMode stackingMode;
};

/*!
    \class QStackedLayout

    \brief The QStackedLayout class provides a stack of widgets where
    only one widget is visible at a time.

    \ingroup geomanagement
    \ingroup appearance
    \mainclass

    QStackedLayout can be used to create a user interface similar to
    the one provided by QTabWidget. There is also a convenience
    QStackedWidget class built on top of QStackedLayout.

    A QStackedLayout can be populated with a number of child widgets
    ("pages"). For example:

    \snippet doc/src/snippets/qstackedlayout/main.cpp 0
    \codeline
    \snippet doc/src/snippets/qstackedlayout/main.cpp 2
    \snippet doc/src/snippets/qstackedlayout/main.cpp 3

    QStackedLayout provides no intrinsic means for the user to switch
    page. This is typically done through a QComboBox or a QListWidget
    that stores the titles of the QStackedLayout's pages. For
    example:

    \snippet doc/src/snippets/qstackedlayout/main.cpp 1

    When populating a layout, the widgets are added to an internal
    list. The indexOf() function returns the index of a widget in that
    list. The widgets can either be added to the end of the list using
    the addWidget() function, or inserted at a given index using the
    insertWidget() function. The removeWidget() function removes the
    widget at the given index from the layout. The number of widgets
    contained in the layout, can be obtained using the count()
    function.

    The widget() function returns the widget at a given index
    position. The index of the widget that is shown on screen is given
    by currentIndex() and can be changed using setCurrentIndex(). In a
    similar manner, the currently shown widget can be retrieved using
    the currentWidget() function, and altered using the
    setCurrentWidget() function.

    Whenever the current widget in the layout changes or a widget is
    removed from the layout, the currentChanged() and widgetRemoved()
    signals are emitted respectively.

    \sa QStackedWidget, QTabWidget
*/

/*!
    \fn void QStackedLayout::currentChanged(int index)

    This signal is emitted whenever the current widget in the layout
    changes.  The \a index specifies the index of the new current
    widget, or -1 if there isn't a new one (for example, if there
    are no widgets in the QStackedLayout)

    \sa currentWidget(), setCurrentWidget()
*/

/*!
    \fn void QStackedLayout::widgetRemoved(int index)

    This signal is emitted whenever a widget is removed from the
    layout. The widget's \a index is passed as parameter.

    \sa removeWidget()
*/

/*!
    \fn QWidget *QStackedLayout::widget()
    \internal
*/

/*!
    Constructs a QStackedLayout with no parent.

    This QStackedLayout must be installed on a widget later on to
    become effective.

    \sa addWidget(), insertWidget()
*/
QStackedLayout::QStackedLayout()
    : QLayout(*new QStackedLayoutPrivate, 0, 0)
{
}

/*!
    Constructs a new QStackedLayout with the given \a parent.

    This layout will install itself on the \a parent widget and
    manage the geometry of its children.
*/
QStackedLayout::QStackedLayout(QWidget *parent)
    : QLayout(*new QStackedLayoutPrivate, 0, parent)
{
}

/*!
    Constructs a new QStackedLayout and inserts it into
    the given \a parentLayout.
*/
QStackedLayout::QStackedLayout(QLayout *parentLayout)
    : QLayout(*new QStackedLayoutPrivate, parentLayout, 0)
{
}

/*!
    Destroys this QStackedLayout. Note that the layout's widgets are
    \e not destroyed.
*/
QStackedLayout::~QStackedLayout()
{
    Q_D(QStackedLayout);
    qDeleteAll(d->list);
}

/*!
    Adds the given \a widget to the end of this layout and returns the
    index position of the \a widget.

    If the QStackedLayout is empty before this function is called,
    the given \a widget becomes the current widget.

    \sa insertWidget(), removeWidget(), setCurrentWidget()
*/
int QStackedLayout::addWidget(QWidget *widget)
{
    Q_D(QStackedLayout);
    return insertWidget(d->list.count(), widget);
}

/*!
    Inserts the given \a widget at the given \a index in this
    QStackedLayout. If \a index is out of range, the widget is
    appended (in which case it is the actual index of the \a widget
    that is returned).

    If the QStackedLayout is empty before this function is called, the