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#include "qdatawidgetmapper.h"

#ifndef QT_NO_DATAWIDGETMAPPER

#include "qabstractitemmodel.h"

#include "qitemdelegate.h"

#include "qmetaobject.h"

#include "qwidget.h"

#include "private/qobject_p.h"

#include "private/qabstractitemmodel_p.h"

QT_BEGIN_NAMESPACE

class QDataWidgetMapperPrivate: public QObjectPrivate

{

public:

    Q_DECLARE_PUBLIC(QDataWidgetMapper)

    QDataWidgetMapperPrivate()

        : model(QAbstractItemModelPrivate::staticEmptyModel()), delegate(0),

          orientation(Qt::Horizontal), submitPolicy(QDataWidgetMapper::AutoSubmit)

    {

    }

    QAbstractItemModel *model;

    QAbstractItemDelegate *delegate;

    Qt::Orientation orientation;

    QDataWidgetMapper::SubmitPolicy submitPolicy;

    QPersistentModelIndex rootIndex;

    QPersistentModelIndex currentTopLeft;

    inline int itemCount()

    {

        return orientation == Qt::Horizontal

            ? model->rowCount(rootIndex)

            : model->columnCount(rootIndex);

    }

    inline int currentIdx() const

    {

        return orientation == Qt::Horizontal ? currentTopLeft.row() : currentTopLeft.column();

    }

    inline QModelIndex indexAt(int itemPos)

    {

        return orientation == Qt::Horizontal

            ? model->index(currentIdx(), itemPos, rootIndex)

            : model->index(itemPos, currentIdx(), rootIndex);

    }

    inline void flipEventFilters(QAbstractItemDelegate *oldDelegate,

                                 QAbstractItemDelegate *newDelegate)

    {

        for (int i = 0; i < widgetMap.count(); ++i) {

            QWidget *w = widgetMap.at(i).widget;

            if (!w)

                continue;

            w->removeEventFilter(oldDelegate);

            w->installEventFilter(newDelegate);

        }

    }

    void populate();

    // private slots

    void _q_dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight);

    void _q_commitData(QWidget *);

    void _q_closeEditor(QWidget *, QAbstractItemDelegate::EndEditHint);

    void _q_modelDestroyed();

    struct WidgetMapper

    {

        inline WidgetMapper(QWidget *w = 0, int c = 0, const QModelIndex &i = QModelIndex())

            : widget(w), section(c), currentIndex(i) {}

        inline WidgetMapper(QWidget *w, int c, const QModelIndex &i, const QByteArray &p)

            : widget(w), section(c), currentIndex(i), property(p) {}

        QPointer<QWidget> widget;

        int section;

        QPersistentModelIndex currentIndex;

        QByteArray property;

    };

    void populate(WidgetMapper &m);

    int findWidget(QWidget *w) const;

    bool commit(const WidgetMapper &m);

    QList<WidgetMapper> widgetMap;

};

int QDataWidgetMapperPrivate::findWidget(QWidget *w) const

{

    for (int i = 0; i < widgetMap.count(); ++i) {

        if (widgetMap.at(i).widget == w)

            return i;

    }

    return -1;

}

bool QDataWidgetMapperPrivate::commit(const WidgetMapper &m)

{

    if (m.widget.isNull())

        return true; // just ignore

    if (!m.currentIndex.isValid())

        return false;

    // Create copy to avoid passing the widget mappers data

    QModelIndex idx = m.currentIndex;

    if (m.property.isEmpty())

        delegate->setModelData(m.widget, model, idx);

    else

        model->setData(idx, m.widget->property(m.property), Qt::EditRole);

    return true;

}

void QDataWidgetMapperPrivate::populate(WidgetMapper &m)

{

    if (m.widget.isNull())

        return;

    m.currentIndex = indexAt(m.section);

    if (m.property.isEmpty())

        delegate->setEditorData(m.widget, m.currentIndex);

    else

        m.widget->setProperty(m.property, m.currentIndex.data(Qt::EditRole));

}

void QDataWidgetMapperPrivate::populate()

{

    for (int i = 0; i < widgetMap.count(); ++i)

        populate(widgetMap[i]);

}

static bool qContainsIndex(const QModelIndex &idx, const QModelIndex &topLeft,

                           const QModelIndex &bottomRight)

{

    return idx.row() >= topLeft.row() && idx.row() <= bottomRight.row()

           && idx.column() >= topLeft.column() && idx.column() <= bottomRight.column();

}

void QDataWidgetMapperPrivate::_q_dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)

{

    if (topLeft.parent() != rootIndex)

        return; // not in our hierarchy

    for (int i = 0; i < widgetMap.count(); ++i) {

        WidgetMapper &m = widgetMap[i];

        if (qContainsIndex(m.currentIndex, topLeft, bottomRight))

            populate(m);

    }

}

void QDataWidgetMapperPrivate::_q_commitData(QWidget *w)

{

    if (submitPolicy == QDataWidgetMapper::ManualSubmit)

        return;

    int idx = findWidget(w);

    if (idx == -1)

        return; // not our widget

    commit(widgetMap.at(idx));

}

class QFocusHelper: public QWidget

{

public:

    bool focusNextPrevChild(bool next)

    {

        return QWidget::focusNextPrevChild(next);

    }

    static inline void focusNextPrevChild(QWidget *w, bool next)

    {

        static_cast<QFocusHelper *>(w)->focusNextPrevChild(next);

    }

};

void QDataWidgetMapperPrivate::_q_closeEditor(QWidget *w, QAbstractItemDelegate::EndEditHint hint)

{

    int idx = findWidget(w);

    if (idx == -1)

        return; // not our widget

    switch (hint) {

    case QAbstractItemDelegate::RevertModelCache: {

        populate(widgetMap[idx]);

        break; }

    case QAbstractItemDelegate::EditNextItem:

        QFocusHelper::focusNextPrevChild(w, true);

        break;

    case QAbstractItemDelegate::EditPreviousItem:

        QFocusHelper::focusNextPrevChild(w, false);

        break;

    case QAbstractItemDelegate::SubmitModelCache:

    case QAbstractItemDelegate::NoHint:

        // nothing

        break;

    }

}

void QDataWidgetMapperPrivate::_q_modelDestroyed()

{

    Q_Q(QDataWidgetMapper);

    model = 0;

    q->setModel(QAbstractItemModelPrivate::staticEmptyModel());

}

/*!

    \class QDataWidgetMapper

    \brief The QDataWidgetMapper class provides mapping between a section

    of a data model to widgets.

    \since 4.2

    \ingroup model-view

    \ingroup advanced

    QDataWidgetMapper can be used to create data-aware widgets by mapping

    them to sections of an item model. A section is a column of a model

    if the orientation is horizontal (the default), otherwise a row.

    Every time the current index changes, each widget is updated with data

    from the model via the property specified when its mapping was made.

    If the user edits the contents of a widget, the changes are read using

    the same property and written back to the model.

    By default, each widget's \l{Q_PROPERTY()}{user property} is used to

    transfer data between the model and the widget. Since Qt 4.3, an

    additional addMapping() function enables a named property to be used

    instead of the default user property.

    It is possible to set an item delegate to support custom widgets. By default,

    a QItemDelegate is used to synchronize the model with the widgets.

    Let us assume that we have an item model named \c{model} with the following contents:

    \table

    \row \o 1 \o Qt Norway       \o Oslo

    \row \o 2 \o Qt Australia    \o Brisbane

    \row \o 3 \o Qt USA          \o Palo Alto

    \row \o 4 \o Qt China        \o Beijing

    \row \o 5 \o Qt Germany      \o Berlin

    \endtable

    The following code will map the columns of the model to widgets called \c mySpinBox,

    \c myLineEdit and \c{myCountryChooser}:

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

    After the call to toFirst(), \c mySpinBox displays the value \c{1}, \c myLineEdit

    displays \c {Nokia Corporation and/or its subsidiary(-ies)} and \c myCountryChooser displays \c{Oslo}. The

    navigational functions toFirst(), toNext(), toPrevious(), toLast() and setCurrentIndex()

    can be used to navigate in the model and update the widgets with contents from

    the model.

    The setRootIndex() function enables a particular item in a model to be

    specified as the root index - children of this item will be mapped to

    the relevant widgets in the user interface.

    QDataWidgetMapper supports two submit policies, \c AutoSubmit and \c{ManualSubmit}.

    \c AutoSubmit will update the model as soon as the current widget loses focus,

    \c ManualSubmit will not update the model unless submit() is called. \c ManualSubmit

    is useful when displaying a dialog that lets the user cancel all modifications.

    Also, other views that display the model won't update until the user finishes

    all their modifications and submits.

    Note that QDataWidgetMapper keeps track of external modifications. If the contents

    of the model are updated in another module of the application, the widgets are

    updated as well.

    \sa QAbstractItemModel, QAbstractItemDelegate

 */

/*! \enum QDataWidgetMapper::SubmitPolicy

    This enum describes the possible submit policies a QDataWidgetMapper

    supports.

    \value AutoSubmit    Whenever a widget loses focus, the widget's current

                         value is set to the item model.

    \value ManualSubmit  The model is not updated until submit() is called.

 */

/*!

    \fn void QDataWidgetMapper::currentIndexChanged(int index)

    This signal is emitted after the current index has changed and

    all widgets were populated with new data. \a index is the new

    current index.

    \sa currentIndex(), setCurrentIndex()

 */

/*!

    Constructs a new QDataWidgetMapper with parent object \a parent.

    By default, the orientation is horizontal and the submit policy

    is \c{AutoSubmit}.

    \sa setOrientation(), setSubmitPolicy()

 */

QDataWidgetMapper::QDataWidgetMapper(QObject *parent)

    : QObject(*new QDataWidgetMapperPrivate, parent)

{

    setItemDelegate(new QItemDelegate(this));

}

/*!

    Destroys the object.

 */

QDataWidgetMapper::~QDataWidgetMapper()

{

}

/*!

     Sets the current model to \a model. If another model was set,

     all mappings to that old model are cleared.

     \sa model()

 */

void QDataWidgetMapper::setModel(QAbstractItemModel *model)

{

    Q_D(QDataWidgetMapper);

    if (d->model == model)

        return;

    if (d->model) {

        disconnect(d->model, SIGNAL(dataChanged(QModelIndex,QModelIndex)), this,

                   SLOT(_q_dataChanged(QModelIndex,QModelIndex)));

        disconnect(d->model, SIGNAL(destroyed()), this,

                   SLOT(_q_modelDestroyed()));

    }

    clearMapping();

    d->rootIndex = QModelIndex();

    d->currentTopLeft = QModelIndex();

    d->model = model;

    connect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),

            SLOT(_q_dataChanged(QModelIndex,QModelIndex)));

    connect(model, SIGNAL(destroyed()), SLOT(_q_modelDestroyed()));

}

/*!

    Returns the current model.

    \sa setModel()

 */

QAbstractItemModel *QDataWidgetMapper::model() const

{

    Q_D(const QDataWidgetMapper);

    return d->model == QAbstractItemModelPrivate::staticEmptyModel()

            ? static_cast<QAbstractItemModel *>(0)

            : d->model;

}

/*!

    Sets the item delegate to \a delegate. The delegate will be used to write

    data from the model into the widget and from the widget to the model,

    using QAbstractItemDelegate::setEditorData() and QAbstractItemDelegate::setModelData().

    The delegate also decides when to apply data and when to change the editor,

    using QAbstractItemDelegate::commitData() and QAbstractItemDelegate::closeEditor().

    \warning You should not share the same instance of a delegate between widget mappers

    or views. Doing so can cause incorrect or unintuitive editing behavior since each

    view connected to a given delegate may receive the \l{QAbstractItemDelegate::}{closeEditor()}

    signal, and attempt to access, modify or close an editor that has already been closed.

 */

void QDataWidgetMapper::setItemDelegate(QAbstractItemDelegate *delegate)

{

    Q_D(QDataWidgetMapper);

    QAbstractItemDelegate *oldDelegate = d->delegate;

    if (oldDelegate) {

        disconnect(oldDelegate, SIGNAL(commitData(QWidget*)), this, SLOT(_q_commitData(QWidget*)));

        disconnect(oldDelegate, SIGNAL(closeEditor(QWidget*,QAbstractItemDelegate::EndEditHint)),

                   this, SLOT(_q_closeEditor(QWidget*,QAbstractItemDelegate::EndEditHint)));

    }

    d->delegate = delegate;

    if (delegate) {

        connect(delegate, SIGNAL(commitData(QWidget*)), SLOT(_q_commitData(QWidget*)));

        connect(delegate, SIGNAL(closeEditor(QWidget*,QAbstractItemDelegate::EndEditHint)),

                SLOT(_q_closeEditor(QWidget*,QAbstractItemDelegate::EndEditHint)));

    }

    d->flipEventFilters(oldDelegate, delegate);

}

/*!

    Returns the current item delegate.

 */

QAbstractItemDelegate *QDataWidgetMapper::itemDelegate() const

{

    Q_D(const QDataWidgetMapper);

    return d->delegate;

}

/*!

    Sets the root item to \a index. This can be used to display

    a branch of a tree. Pass an invalid model index to display

    the top-most branch.

    \sa rootIndex()

 */

void QDataWidgetMapper::setRootIndex(const QModelIndex &index)

{

    Q_D(QDataWidgetMapper);

    d->rootIndex = index;

}

/*!

    Returns the current root index.

    \sa setRootIndex()

*/

QModelIndex QDataWidgetMapper::rootIndex() const

{

    Q_D(const QDataWidgetMapper);

    return QModelIndex(d->rootIndex);

}

/*!

    Adds a mapping between a \a widget and a \a section from the model.

    The \a section is a column in the model if the orientation is

    horizontal (the default), otherwise a row.

    For the following example, we assume a model \c myModel that

    has two columns: the first one contains the names of people in a

    group, and the second column contains their ages. The first column

    is mapped to the QLineEdit \c nameLineEdit, and the second is

    mapped to the QSpinBox \c{ageSpinBox}:

    \snippet doc/src/snippets/code/src_gui_itemviews_qdatawidgetmapper.cpp 1

    \bold{Notes:}

    \list

    \o If the \a widget is already mapped to a section, the

    old mapping will be replaced by the new one.

    \o Only one-to-one mappings between sections and widgets are allowed.

    It is not possible to map a single section to multiple widgets, or to

    map a single widget to multiple sections.

    \endlist

    \sa removeMapping(), mappedSection(), clearMapping()

 */

void QDataWidgetMapper::addMapping(QWidget *widget, int section)

{

    Q_D(QDataWidgetMapper);

    removeMapping(widget);

    d->widgetMap.append(QDataWidgetMapperPrivate::WidgetMapper(widget, section, d->indexAt(section)));

    widget->installEventFilter(d->delegate);

}

/*!

  \since 4.3

  Essentially the same as addMapping(), but adds the possibility to specify

  the property to use specifying \a propertyName.

  \sa addMapping()

*/

void QDataWidgetMapper::addMapping(QWidget *widget, int section, const QByteArray &propertyName)

{

    Q_D(QDataWidgetMapper);

    removeMapping(widget);

    d->widgetMap.append(QDataWidgetMapperPrivate::WidgetMapper(widget, section, d->indexAt(section), propertyName));

    widget->installEventFilter(d->delegate);

}

/*!

    Removes the mapping for the given \a widget.

    \sa addMapping(), clearMapping()

 */

void QDataWidgetMapper::removeMapping(QWidget *widget)

{

    Q_D(QDataWidgetMapper);

    int idx = d->findWidget(widget);

    if (idx == -1)