summaryrefslogtreecommitdiffstats
path: root/src/declarative/util/qdeclarativestate.cpp
blob: 802ff1ca3178d22ac00b89a5c2a153eab9fbbe35 (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
/****************************************************************************
**
** 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 "qdeclarativestate_p_p.h"
#include "qdeclarativestate_p.h"

#include "qdeclarativetransition_p.h"
#include "qdeclarativestategroup_p.h"
#include "qdeclarativestateoperations_p.h"
#include "qdeclarativeanimation_p.h"
#include "qdeclarativeanimation_p_p.h"

#include <qdeclarativebinding_p.h>
#include <qdeclarativeglobal_p.h>

#include <QtCore/qdebug.h>

QT_BEGIN_NAMESPACE

DEFINE_BOOL_CONFIG_OPTION(stateChangeDebug, STATECHANGE_DEBUG);

QDeclarativeAction::QDeclarativeAction()
: restore(true), actionDone(false), reverseEvent(false), deletableToBinding(false), fromBinding(0), toBinding(0), event(0),
  specifiedObject(0)
{
}

QDeclarativeAction::QDeclarativeAction(QObject *target, const QString &propertyName,
               const QVariant &value)
: restore(true), actionDone(false), reverseEvent(false), deletableToBinding(false), 
  property(target, propertyName), toValue(value), 
  fromBinding(0), toBinding(0), event(0), 
  specifiedObject(target), specifiedProperty(propertyName)
{
    if (property.isValid())
        fromValue = property.read();
}

QDeclarativeActionEvent::~QDeclarativeActionEvent()
{
}

QString QDeclarativeActionEvent::typeName() const
{
    return QString();
}

void QDeclarativeActionEvent::execute()
{
}

bool QDeclarativeActionEvent::isReversable()
{
    return false;
}

void QDeclarativeActionEvent::reverse()
{
}

bool QDeclarativeActionEvent::changesBindings()
{
    return false;
}

void QDeclarativeActionEvent::clearBindings()
{
}

bool QDeclarativeActionEvent::override(QDeclarativeActionEvent *other)
{
    Q_UNUSED(other);
    return false;
}

/*!
    \internal
*/
QDeclarativeStateOperation::QDeclarativeStateOperation(QObjectPrivate &dd, QObject *parent)
    : QObject(dd, parent)
{
}

/*!
    \qmlclass State QDeclarativeState
  \since 4.7
    \brief The State element defines configurations of objects and properties.

    A state is specified as a set of batched changes from the default configuration.

    Note that setting the state of an object from within another state of the same object is
    inadvisible. Not only would this have the same effect as going directly to the second state
    it may cause the program to crash.

    \sa {qmlstates}{States}, {state-transitions}{Transitions}
*/

/*!
    \internal
    \class QDeclarativeState
    \brief The QDeclarativeState class allows you to define configurations of objects and properties.

    \ingroup group_states

    QDeclarativeState allows you to specify a state as a set of batched changes from the default
    configuration.

    \sa {states-transitions}{States and Transitions}
*/


QDeclarativeState::QDeclarativeState(QObject *parent)
: QObject(*(new QDeclarativeStatePrivate), parent)
{
    Q_D(QDeclarativeState);
    d->transitionManager.setState(this);
}

QDeclarativeState::~QDeclarativeState()
{
    Q_D(QDeclarativeState);
    if (d->group)
        d->group->removeState(this);
}

/*!
    \qmlproperty string State::name
    This property holds the name of the state

    Each state should have a unique name.
*/
QString QDeclarativeState::name() const
{
    Q_D(const QDeclarativeState);
    return d->name;
}

void QDeclarativeState::setName(const QString &n)
{
    Q_D(QDeclarativeState);
    d->name = n;
}

bool QDeclarativeState::isWhenKnown() const
{
    Q_D(const QDeclarativeState);
    return d->when != 0;
}

/*!
    \qmlproperty bool State::when
    This property holds when the state should be applied

    This should be set to an expression that evaluates to true when you want the state to
    be applied.
*/
QDeclarativeBinding *QDeclarativeState::when() const
{
    Q_D(const QDeclarativeState);
    return d->when;
}

void QDeclarativeState::setWhen(QDeclarativeBinding *when)
{
    Q_D(QDeclarativeState);
    d->when = when;
    if (d->group)
        d->group->updateAutoState();
}

/*!
    \qmlproperty string State::extend
    This property holds the state that this state extends

    The state being extended is treated as the base state in regards to
    the changes specified by the extending state.
*/
QString QDeclarativeState::extends() const
{
    Q_D(const QDeclarativeState);
    return d->extends;
}

void QDeclarativeState::setExtends(const QString &extends)
{
    Q_D(QDeclarativeState);
    d->extends = extends;
}

/*!
    \qmlproperty list<Change> State::changes
    This property holds the changes to apply for this state
    \default

    By default these changes are applied against the default state. If the state
    extends another state, then the changes are applied against the state being
    extended.
*/
QDeclarativeListProperty<QDeclarativeStateOperation> QDeclarativeState::changes()
{
    Q_D(QDeclarativeState);
    return QDeclarativeListProperty<QDeclarativeStateOperation>(this, &d->operations, QDeclarativeStatePrivate::operations_append,
                                              QDeclarativeStatePrivate::operations_count, QDeclarativeStatePrivate::operations_at,
                                              QDeclarativeStatePrivate::operations_clear);
}

int QDeclarativeState::operationCount() const
{
    Q_D(const QDeclarativeState);
    return d->operations.count();
}

QDeclarativeStateOperation *QDeclarativeState::operationAt(int index) const
{
    Q_D(const QDeclarativeState);
    return d->operations.at(index);
}

QDeclarativeState &QDeclarativeState::operator<<(QDeclarativeStateOperation *op)
{
    Q_D(QDeclarativeState);
    d->operations.append(QDeclarativeStatePrivate::OperationGuard(op, &d->operations));
    return *this;
}

void QDeclarativeStatePrivate::complete()
{
    Q_Q(QDeclarativeState);

    for (int ii = 0; ii < reverting.count(); ++ii) {
        for (int jj = 0; jj < revertList.count(); ++jj) {
            if (revertList.at(jj).property == reverting.at(ii)) {
                revertList.removeAt(jj);
                break;
            }
        }
    }
    reverting.clear();

    emit q->completed();
}

// Generate a list of actions for this state.  This includes coelescing state
// actions that this state "extends"
QDeclarativeStateOperation::ActionList
QDeclarativeStatePrivate::generateActionList(QDeclarativeStateGroup *group) const
{
    QDeclarativeStateOperation::ActionList applyList;
    if (inState)
        return applyList;

    // Prevent "extends" recursion
    inState = true;

    if (!extends.isEmpty()) {
        QList<QDeclarativeState *> states = group->states();
        for (int ii = 0; ii < states.count(); ++ii)
            if (states.at(ii)->name() == extends)
                applyList = static_cast<QDeclarativeStatePrivate*>(states.at(ii)->d_func())->generateActionList(group);
    }

    foreach(QDeclarativeStateOperation *op, operations)
        applyList << op->actions();

    inState = false;
    return applyList;
}

QDeclarativeStateGroup *QDeclarativeState::stateGroup() const
{
    Q_D(const QDeclarativeState);
    return d->group;
}

void QDeclarativeState::setStateGroup(QDeclarativeStateGroup *group)
{
    Q_D(QDeclarativeState);
    d->group = group;
}

void QDeclarativeState::cancel()
{
    Q_D(QDeclarativeState);
    d->transitionManager.cancel();
}

void QDeclarativeAction::deleteFromBinding()
{
    if (fromBinding) {
        QDeclarativePropertyPrivate::setBinding(property, 0);
        fromBinding->destroy();
        fromBinding = 0;
    }
}

void QDeclarativeState::apply(QDeclarativeStateGroup *group, QDeclarativeTransition *trans, QDeclarativeState *revert)
{
    Q_D(QDeclarativeState);

    qmlExecuteDeferred(this);

    cancel();
    if (revert)
        revert->cancel();
    d->revertList.clear();
    d->reverting.clear();

    if (revert) {
        QDeclarativeStatePrivate *revertPrivate =
            static_cast<QDeclarativeStatePrivate*>(revert->d_func());
        d->revertList = revertPrivate->revertList;
        revertPrivate->revertList.clear();
    }

    // List of actions caused by this state
    QDeclarativeStateOperation::ActionList applyList = d->generateActionList(group);

    // List of actions that need to be reverted to roll back (just) this state
    QDeclarativeStatePrivate::SimpleActionList additionalReverts;
    // First add the reverse of all the applyList actions
    for (int ii = 0; ii < applyList.count(); ++ii) {
        QDeclarativeAction &action = applyList[ii];

        if (action.event) {
            if (!action.event->isReversable())
                continue;
            bool found = false;
            for (int jj = 0; jj < d->revertList.count(); ++jj) {
                QDeclarativeActionEvent *event = d->revertList.at(jj).event;
                if (event && event->typeName() == action.event->typeName()) {
                    if (action.event->override(event)) {
                        found = true;

                        if (action.event != d->revertList.at(jj).event) {
                            action.event->copyOriginals(d->revertList.at(jj).event);

                            QDeclarativeSimpleAction r(action);
                            additionalReverts << r;
                            d->revertList.removeAt(jj);
                        } else if (action.event->isRewindable())    //###why needed?
                            action.event->saveCurrentValues();

                        break;
                    }
                }
            }
            if (!found) {
                action.event->saveOriginals();
                // Only need to revert the applyList action if the previous
                // state doesn't have a higher priority revert already
                QDeclarativeSimpleAction r(action);
                additionalReverts << r;
            }
        } else {
            bool found = false;
            action.fromBinding = QDeclarativePropertyPrivate::binding(action.property);

            for (int jj = 0; jj < d->revertList.count(); ++jj) {
                if (d->revertList.at(jj).property == action.property) {
                    found = true;
                    if (d->revertList.at(jj).binding != action.fromBinding) {
                        action.deleteFromBinding();
                    }
                    break;
                }
            }

            if (!found) {
                if (!action.restore) {
                    action.deleteFromBinding();
                } else {
                    // Only need to revert the applyList action if the previous
                    // state doesn't have a higher priority revert already
                    QDeclarativeSimpleAction r(action);
                    additionalReverts << r;
                }
            }
        }
    }

    // Any reverts from a previous state that aren't carried forth
    // into this state need to be translated into apply actions
    for (int ii = 0; ii < d->revertList.count(); ++ii) {
        bool found = false;
        if (d->revertList.at(ii).event) {
            QDeclarativeActionEvent *event = d->revertList.at(ii).event;
            if (!event->isReversable())
                continue;
            for (int jj = 0; !found && jj < applyList.count(); ++jj) {
                const QDeclarativeAction &action = applyList.at(jj);
                if (action.event && action.event->typeName() == event->typeName()) {
                    if (action.event->override(event))
                        found = true;
                }
            }
        } else {
            for (int jj = 0; !found && jj < applyList.count(); ++jj) {
                const QDeclarativeAction &action = applyList.at(jj);
                if (action.property == d->revertList.at(ii).property)
                    found = true;
            }
        }
        if (!found) {
            QVariant cur = d->revertList.at(ii).property.read();
            QDeclarativeAbstractBinding *delBinding = 
                QDeclarativePropertyPrivate::setBinding(d->revertList.at(ii).property, 0);
            if (delBinding)
                delBinding->destroy();

            QDeclarativeAction a;
            a.property = d->revertList.at(ii).property;
            a.fromValue = cur;
            a.toValue = d->revertList.at(ii).value;
            a.toBinding = d->revertList.at(ii).binding;
            a.specifiedObject = d->revertList.at(ii).specifiedObject;
            a.specifiedProperty = d->revertList.at(ii).specifiedProperty;
            a.event = d->revertList.at(ii).event;
            a.reverseEvent = d->revertList.at(ii).reverseEvent;
            if (a.event && a.event->isRewindable())
                a.event->saveCurrentValues();
            applyList << a;
            // Store these special reverts in the reverting list
            d->reverting << d->revertList.at(ii).property;
        }
    }
    // All the local reverts now become part of the ongoing revertList
    d->revertList << additionalReverts;

    // Output for debugging
    if (stateChangeDebug()) {
        foreach(const QDeclarativeAction &action, applyList) {
            if (action.event)
                qWarning() << "    QDeclarativeAction event:" << action.event->typeName();
            else
                qWarning() << "    QDeclarativeAction:" << action.property.object()
                           << action.property.name() << "From:" << action.fromValue 
                           << "To:" << action.toValue;
        }
    }

    d->transitionManager.transition(applyList, trans);
}

QDeclarativeStateOperation::ActionList QDeclarativeStateOperation::actions()
{
    return ActionList();
}

QT_END_NAMESPACE