summaryrefslogtreecommitdiffstats
path: root/src/declarative/graphicsitems/qdeclarativeloader.cpp
blob: b0499d73cef09fb781ede3cce9c81b4687a45c1c (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
/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtDeclarative module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, 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.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qdeclarativeloader_p_p.h"

#include <qdeclarativeengine_p.h>

QT_BEGIN_NAMESPACE

QDeclarativeLoaderPrivate::QDeclarativeLoaderPrivate()
    : item(0), component(0), ownComponent(false)
    , resizeMode(QDeclarativeLoader::SizeLoaderToItem)
{
}

QDeclarativeLoaderPrivate::~QDeclarativeLoaderPrivate()
{
}

void QDeclarativeLoaderPrivate::itemGeometryChanged(QDeclarativeItem *resizeItem, const QRectF &newGeometry, const QRectF &oldGeometry)
{
    if (resizeItem == item && resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
        _q_updateSize();
    }
    QDeclarativeItemChangeListener::itemGeometryChanged(resizeItem, newGeometry, oldGeometry);
}

void QDeclarativeLoaderPrivate::clear()
{
    if (ownComponent) {
        delete component;
        component = 0;
        ownComponent = false;
    }
    source = QUrl();

    if (item) {
        if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
            if (resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
                QDeclarativeItemPrivate *p =
                    static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
                p->removeItemChangeListener(this, QDeclarativeItemPrivate::Geometry);
            }
        }

        // We can't delete immediately because our item may have triggered
        // the Loader to load a different item.
        item->setVisible(false);
        item->setParentItem(0);
        item->deleteLater();
        item = 0;
    }
}

void QDeclarativeLoaderPrivate::initResize()
{
    Q_Q(QDeclarativeLoader);
    if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
        if (resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
            QDeclarativeItemPrivate *p =
                static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
            p->addItemChangeListener(this, QDeclarativeItemPrivate::Geometry);
        }
    } else if (item && item->isWidget()) {
        QGraphicsWidget *widget = static_cast<QGraphicsWidget*>(item);
        if (resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
            widget->installEventFilter(q);
        }
    }
    _q_updateSize();
}

/*!
    \qmlclass Loader QDeclarativeLoader
    \since 4.7
    \inherits Item

    \brief The Loader item allows dynamically loading an Item-based
    subtree from a QML URL or Component.

    Loader instantiates an item from a component. The component to
    instantiate may be specified directly by the \c sourceComponent
    property, or loaded from a URL via the \c source property.

    It is also an effective means of delaying the creation of a component
    until it is required:
    \code
    Loader { id: pageLoader }
    Rectangle {
        MouseArea { anchors.fill: parent; onClicked: pageLoader.source = "Page1.qml" }
    }
    \endcode

    If the Loader source is changed, any previous items instantiated
    will be destroyed.  Setting \c source to an empty string
    will destroy the currently instantiated items, freeing resources
    and leaving the Loader empty.  For example:

    \code
    pageLoader.source = ""
    \endcode

    unloads "Page1.qml" and frees resources consumed by it.

    \sa {dynamic-object-creation}{Dynamic Object Creation}
*/

/*!
    \internal
    \class QDeclarativeLoader
    \qmlclass Loader
 */

/*!
    Create a new QDeclarativeLoader instance.
 */
QDeclarativeLoader::QDeclarativeLoader(QDeclarativeItem *parent)
  : QDeclarativeItem(*(new QDeclarativeLoaderPrivate), parent)
{
}

/*!
    Destroy the loader instance.
 */
QDeclarativeLoader::~QDeclarativeLoader()
{
}

/*!
    \qmlproperty url Loader::source
    This property holds the URL of the QML component to
    instantiate.

    \sa sourceComponent, status, progress
*/
QUrl QDeclarativeLoader::source() const
{
    Q_D(const QDeclarativeLoader);
    return d->source;
}

void QDeclarativeLoader::setSource(const QUrl &url)
{
    Q_D(QDeclarativeLoader);
    if (d->source == url)
        return;

    d->clear();

    d->source = url;
    if (d->source.isEmpty()) {
        emit sourceChanged();
        emit statusChanged();
        emit progressChanged();
        emit itemChanged();
        return;
    }

    d->component = new QDeclarativeComponent(qmlEngine(this), d->source, this);
    d->ownComponent = true;
    if (!d->component->isLoading()) {
        d->_q_sourceLoaded();
    } else {
        connect(d->component, SIGNAL(statusChanged(QDeclarativeComponent::Status)),
                this, SLOT(_q_sourceLoaded()));
        connect(d->component, SIGNAL(progressChanged(qreal)),
                this, SIGNAL(progressChanged()));
        emit statusChanged();
        emit progressChanged();
        emit sourceChanged();
        emit itemChanged();
    }
}

/*!
    \qmlproperty Component Loader::sourceComponent
    The sourceComponent property holds the \l{Component} to instantiate.

    \qml
    Item {
        Component {
            id: redSquare
            Rectangle { color: "red"; width: 10; height: 10 }
        }

        Loader { sourceComponent: redSquare }
        Loader { sourceComponent: redSquare; x: 10 }
    }
    \endqml

    \sa source, progress
*/

QDeclarativeComponent *QDeclarativeLoader::sourceComponent() const
{
    Q_D(const QDeclarativeLoader);
    return d->component;
}

void QDeclarativeLoader::setSourceComponent(QDeclarativeComponent *comp)
{
    Q_D(QDeclarativeLoader);
    if (comp == d->component)
        return;

    d->clear();

    d->component = comp;
    d->ownComponent = false;
    if (!d->component) {
        emit sourceChanged();
        emit statusChanged();
        emit progressChanged();
        emit itemChanged();
        return;
    }

    if (!d->component->isLoading()) {
        d->_q_sourceLoaded();
    } else {
        connect(d->component, SIGNAL(statusChanged(QDeclarativeComponent::Status)),
                this, SLOT(_q_sourceLoaded()));
        connect(d->component, SIGNAL(progressChanged(qreal)),
                this, SIGNAL(progressChanged()));
        emit progressChanged();
        emit sourceChanged();
        emit statusChanged();
        emit itemChanged();
    }
}

void QDeclarativeLoaderPrivate::_q_sourceLoaded()
{
    Q_Q(QDeclarativeLoader);

    if (component) {
        QDeclarativeContext *ctxt = new QDeclarativeContext(qmlContext(q));
        ctxt->addDefaultObject(q);

        if (!component->errors().isEmpty()) {
            qWarning() << component->errors();
            emit q->sourceChanged();
            emit q->statusChanged();
            emit q->progressChanged();
            return;
        }

        QObject *obj = component->create(ctxt);
        if (obj) {
            ctxt->setParent(obj);
            item = qobject_cast<QGraphicsObject *>(obj);
            if (item) {
                if (QDeclarativeItem* qmlItem = qobject_cast<QDeclarativeItem *>(item)) {
                    qmlItem->setParentItem(q);
                } else {
                    item->setParentItem(q);
                    item->setParent(q);
                }
//                item->setFocus(true);
                initResize();
            }
        } else {
            delete obj;
            delete ctxt;
            source = QUrl();
        }
        emit q->sourceChanged();
        emit q->statusChanged();
        emit q->progressChanged();
        emit q->itemChanged();
    }
}

/*!
    \qmlproperty enum Loader::status

    This property holds the status of QML loading.  It can be one of:
    \list
    \o Null - no QML source has been set
    \o Ready - the QML source has been loaded
    \o Loading - the QML source is currently being loaded
    \o Error - an error occurred while loading the QML source
    \endlist

    Note that a change in the status property does not cause anything to happen
    (although it reflects what has happened to the loader internally). If you wish
    to react to the change in status you need to do it yourself, for example in one
    of the following ways:
    \list
    \o Create a state, so that a state change occurs, e.g. State{name: 'loaded'; when: loader.status = Loader.Ready;}
    \o Do something inside the onStatusChanged signal handler, e.g. Loader{id: loader; onStatusChanged: if(loader.status == Loader.Ready) console.log('Loaded');}
    \o Bind to the status variable somewhere, e.g. Text{text: if(loader.status!=Loader.Ready){'Not Loaded';}else{'Loaded';}}
    \endlist
    \sa progress
*/

QDeclarativeLoader::Status QDeclarativeLoader::status() const
{
    Q_D(const QDeclarativeLoader);

    if (d->component)
        return static_cast<QDeclarativeLoader::Status>(d->component->status());

    if (d->item)
        return Ready;

    return d->source.isEmpty() ? Null : Error;
}

/*!
    \qmlproperty real Loader::progress

    This property holds the progress of QML data loading, from 0.0 (nothing loaded)
    to 1.0 (finished).

    \sa status
*/
qreal QDeclarativeLoader::progress() const
{
    Q_D(const QDeclarativeLoader);

    if (d->item)
        return 1.0;

    if (d->component)
        return d->component->progress();

    return 0.0;
}

/*!
    \qmlproperty enum Loader::resizeMode

    This property determines how the Loader or item are resized:
    \list
    \o NoResize - no item will be resized
    \o SizeLoaderToItem - the Loader will be sized to the size of the item, unless the size of the Loader has been otherwise specified.
    \o SizeItemToLoader - the item will be sized to the size of the Loader.
    \endlist

    Note that changing from SizeItemToLoader to SizeLoaderToItem
    after the component is loaded will not return the item or Loader
    to it's original size.  This is due to the item size being adjusted
    to the Loader size, thereby losing the original size of the item.
    Future changes to the item's size will affect the loader, however.

    The default resizeMode is SizeLoaderToItem.
*/
QDeclarativeLoader::ResizeMode QDeclarativeLoader::resizeMode() const
{
    Q_D(const QDeclarativeLoader);
    return d->resizeMode;
}

void QDeclarativeLoader::setResizeMode(ResizeMode mode)
{
    Q_D(QDeclarativeLoader);
    if (mode == d->resizeMode)
        return;

    if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(d->item)) {
        if (d->resizeMode == SizeLoaderToItem) {
            QDeclarativeItemPrivate *p =
                static_cast<QDeclarativeItemPrivate *>(QGraphicsItemPrivate::get(qmlItem));
            p->removeItemChangeListener(d, QDeclarativeItemPrivate::Geometry);
        }
    } else if (d->item && d->item->isWidget()) {
        if (d->resizeMode == SizeLoaderToItem)
            d->item->removeEventFilter(this);
    }

    d->resizeMode = mode;
    emit resizeModeChanged();
    d->initResize();
}

void QDeclarativeLoaderPrivate::_q_updateSize()
{
    Q_Q(QDeclarativeLoader);
    if (!item)
        return;
    if (QDeclarativeItem *qmlItem = qobject_cast<QDeclarativeItem*>(item)) {
        if (resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
            q->setWidth(qmlItem->width());
            q->setHeight(qmlItem->height());
        } else if (resizeMode == QDeclarativeLoader::SizeItemToLoader) {
            qmlItem->setWidth(q->width());
            qmlItem->setHeight(q->height());
        }
    } else if (item && item->isWidget()) {
        QGraphicsWidget *widget = static_cast<QGraphicsWidget*>(item);
        if (resizeMode == QDeclarativeLoader::SizeLoaderToItem) {
            QSizeF newSize = widget->size();
            if (newSize.isValid()) {
                q->setWidth(newSize.width());
                q->setHeight(newSize.height());
            }
        } else if (resizeMode == QDeclarativeLoader::SizeItemToLoader) {
            QSizeF oldSize = widget->size();
            QSizeF newSize = oldSize;
            if (q->heightValid())
                newSize.setHeight(q->height());
            if (q->widthValid())
                newSize.setWidth(q->width());
            if (oldSize != newSize)
                widget->resize(newSize);
        }
    }
}

/*!
    \qmlproperty Item Loader::item
    This property holds the top-level item created from source.
*/
QGraphicsObject *QDeclarativeLoader::item() const
{
    Q_D(const QDeclarativeLoader);
    return d->item;
}

void QDeclarativeLoader::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_D(QDeclarativeLoader);
    if (newGeometry != oldGeometry) {
        if (d->resizeMode == SizeItemToLoader) {
            d->_q_updateSize();
        }
    }
    QDeclarativeItem::geometryChanged(newGeometry, oldGeometry);
}

QVariant QDeclarativeLoader::itemChange(GraphicsItemChange change, const QVariant &value)
{
    Q_D(QDeclarativeLoader);
    if (change == ItemSceneHasChanged) {
        if (d->item && d->item->isWidget()) {
            if (d->resizeMode == SizeLoaderToItem) {
                d->item->removeEventFilter(this);
                d->item->installEventFilter(this);
            }
        }
    }
    return QDeclarativeItem::itemChange(change, value);
}

bool QDeclarativeLoader::eventFilter(QObject *watched, QEvent *e)
{
    Q_D(QDeclarativeLoader);
    if (watched == d->item && e->type() == QEvent::GraphicsSceneResize) {
        if (d->item && d->item->isWidget() && d->resizeMode == SizeLoaderToItem) {
            d->_q_updateSize();
       }
    }
    return QDeclarativeItem::eventFilter(watched, e);
}

#include <moc_qdeclarativeloader_p.cpp>

QT_END_NAMESPACE