summaryrefslogtreecommitdiffstats
path: root/src/gui/itemviews/qdatawidgetmapper.cpp
blob: 43eace1badc97dc0f8095f6296f49f5af47a7963 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#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{Qt Norway} 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)
        return;

    d->widgetMap.removeAt(idx);
    widget->removeEventFilter(d->delegate);
}

/*!
    Returns the section the \a widget is mapped to or -1
    if the widget is not mapped.

    \sa addMapping(), removeMapping()
 */
int QDataWidgetMapper::mappedSection(QWidget *widget) const
{
    Q_D(const QDataWidgetMapper);

    int idx = d->findWidget(widget);
    if (idx == -1)
        return -1;

    return d->widgetMap.at(idx).section;
}

/*!
  \since 4.3
  Returns the name of the property that is used when mapping
  data to the given \a widget.

  \sa mappedSection(), addMapping(), removeMapping()
*/

QByteArray QDataWidgetMapper::mappedPropertyName(QWidget *widget) const
{
    Q_D(const QDataWidgetMapper);

    int idx = d->findWidget(widget);
    if (idx == -1)
        return QByteArray();
    const QDataWidgetMapperPrivate::WidgetMapper &m = d->widgetMap.at(idx);
    if (m.property.isEmpty())
        return m.widget->metaObject()->userProperty().name();
    else
        return m.property;
}

/*!
    Returns the widget that is mapped at \a section, or
    0 if no widget is mapped at that section.

    \sa addMapping(), removeMapping()
 */
QWidget *QDataWidgetMapper::mappedWidgetAt(int section) const
{
    Q_D(const QDataWidgetMapper);

    for (int i = 0; i < d->widgetMap.count(); ++i) {
        if (d->widgetMap.at(i).section == section)
            return d->widgetMap.at(i).widget;
    }

    return 0;
}

/*!
    Repopulates all widgets with the current data of the model.
    All unsubmitted changes will be lost.

    \sa submit(), setSubmitPolicy()
 */
void QDataWidgetMapper::revert()
{
    Q_D(QDataWidgetMapper);

    d->populate();
}

/*!
    Submits all changes from the mapped widgets to the model.

    For every mapped section, the item delegate reads the current
    value from the widget and sets it in the model. Finally, the
    model's \l {QAbstractItemModel::}{submit()} method is invoked.

    Returns true if all the values were submitted, otherwise false.

    Note: For database models, QSqlQueryModel::lastError() can be
    used to retrieve the last error.

    \sa revert(), setSubmitPolicy()
 */
bool QDataWidgetMapper::submit()
{
    Q_D(QDataWidgetMapper);

    for (int i = 0; i < d->widgetMap.count(); ++i) {
        const QDataWidgetMapperPrivate::WidgetMapper &m = d->widgetMap.at(i);
        if (!d->commit(m))
            return false;
    }

    return d->model->submit();
}

/*!
    Populates the widgets with data from the first row of the model
    if the orientation is horizontal (the default), otherwise
    with data from the first column.

    This is equivalent to calling \c setCurrentIndex(0).

    \sa toLast(), setCurrentIndex()
 */
void QDataWidgetMapper::toFirst()
{
    setCurrentIndex(0);
}

/*!
    Populates the widgets with data from the last row of the model
    if the orientation is horizontal (the default), otherwise
    with data from the last column.

    Calls setCurrentIndex() internally.

    \sa toFirst(), setCurrentIndex()
 */
void QDataWidgetMapper::toLast()
{
    Q_D(QDataWidgetMapper);
    setCurrentIndex(d->itemCount() - 1);
}


/*!
    Populates the widgets with data from the next row of the model
    if the orientation is horizontal (the default), otherwise
    with data from the next column.

    Calls setCurrentIndex() internally. Does nothing if there is
    no next row in the model.

    \sa toPrevious(), setCurrentIndex()
 */
void QDataWidgetMapper::toNext()
{
    Q_D(QDataWidgetMapper);
    setCurrentIndex(d->currentIdx() + 1);
}

/*!
    Populates the widgets with data from the previous row of the model
    if the orientation is horizontal (the default), otherwise
    with data from the previous column.

    Calls setCurrentIndex() internally. Does nothing if there is
    no previous row in the model.

    \sa toNext(), setCurrentIndex()
 */
void QDataWidgetMapper::toPrevious()
{
    Q_D(QDataWidgetMapper);
    setCurrentIndex(d->currentIdx() - 1);
}

/*!
    \property QDataWidgetMapper::currentIndex
    \brief the current row or column

    The widgets are populated with with data from the row at \a index
    if the orientation is horizontal (the default), otherwise with
    data from the column at \a index.

    \sa setCurrentModelIndex(), toFirst(), toNext(), toPrevious(), toLast()
*/
void QDataWidgetMapper::setCurrentIndex(int index)
{
    Q_D(QDataWidgetMapper);

    if (index < 0 || index >= d->itemCount())
        return;
    d->currentTopLeft = d->orientation == Qt::Horizontal
                            ? d->model->index(index, 0, d->rootIndex)
                            : d->model->index(0, index, d->rootIndex);
    d->populate();

    emit currentIndexChanged(index);
}

int QDataWidgetMapper::currentIndex() const
{
    Q_D(const QDataWidgetMapper);
    return d->currentIdx();
}

/*!
    Sets the current index to the row of the \a index if the
    orientation is horizontal (the default), otherwise to the
    column of the \a index.

    Calls setCurrentIndex() internally. This convenience slot can be
    connected to the signal \l
    {QItemSelectionModel::}{currentRowChanged()} or \l
    {QItemSelectionModel::}{currentColumnChanged()} of another view's
    \l {QItemSelectionModel}{selection model}.

    The following example illustrates how to update all widgets
    with new data whenever the selection of a QTableView named
    \c myTableView changes:

    \snippet doc/src/snippets/code/src_gui_itemviews_qdatawidgetmapper.cpp 2

    \sa currentIndex()
*/
void QDataWidgetMapper::setCurrentModelIndex(const QModelIndex &index)
{
    Q_D(QDataWidgetMapper);

    if (!index.isValid()
        || index.model() != d->model
        || index.parent() != d->rootIndex)
        return;

    setCurrentIndex(d->orientation == Qt::Horizontal ? index.row() : index.column());
}

/*!
    Clears all mappings.

    \sa addMapping(), removeMapping()
 */
void QDataWidgetMapper::clearMapping()
{
    Q_D(QDataWidgetMapper);

    while (!d->widgetMap.isEmpty()) {
        QWidget *w = d->widgetMap.takeLast().widget;
        if (w)
            w->removeEventFilter(d->delegate);
    }
}

/*!
    \property QDataWidgetMapper::orientation
    \brief the orientation of the model

    If the orientation is Qt::Horizontal (the default), a widget is
    mapped to a column of a data model. The widget will be populated
    with the model's data from its mapped column and the row that
    currentIndex() points at.

    Use Qt::Horizontal for tabular data that looks like this:

    \table
    \row \o 1 \o Qt Norway       \o Oslo
    \row \o 2 \o Qt Australia    \o Brisbane
    \row \o 3 \o Qt USA          \o Silicon Valley
    \row \o 4 \o Qt China        \o Beijing
    \row \o 5 \o Qt Germany      \o Berlin
    \endtable

    If the orientation is set to Qt::Vertical, a widget is mapped to
    a row. Calling setCurrentIndex() will change the current column.
    The widget will be populates with the model's data from its
    mapped row and the column that currentIndex() points at.

    Use Qt::Vertical for tabular data that looks like this:

    \table
    \row \o 1 \o 2 \o 3 \o 4 \o 5
    \row \o Qt Norway \o Qt Australia \o Qt USA \o Qt China \o Qt Germany
    \row \o Oslo \o Brisbane \o Silicon Valley \o Beijing \i Berlin
    \endtable

    Changing the orientation clears all existing mappings.
*/
void QDataWidgetMapper::setOrientation(Qt::Orientation orientation)
{
    Q_D(QDataWidgetMapper);

    if (d->orientation == orientation)
        return;

    clearMapping();
    d->orientation = orientation;
}

Qt::Orientation QDataWidgetMapper::orientation() const
{
    Q_D(const QDataWidgetMapper);
    return d->orientation;
}

/*!
    \property QDataWidgetMapper::submitPolicy
    \brief the current submit policy

    Changing the current submit policy will revert all widgets
    to the current data from the model.
*/
void QDataWidgetMapper::setSubmitPolicy(SubmitPolicy policy)
{
    Q_D(QDataWidgetMapper);
    if (policy == d->submitPolicy)
        return;

    revert();
    d->submitPolicy = policy;
}

QDataWidgetMapper::SubmitPolicy QDataWidgetMapper::submitPolicy() const
{
    Q_D(const QDataWidgetMapper);
    return d->submitPolicy;
}

QT_END_NAMESPACE

#include "moc_qdatawidgetmapper.cpp"

#endif // QT_NO_DATAWIDGETMAPPER