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
|
/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore 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 "qstate.h"
#ifndef QT_NO_STATEMACHINE
#include "qstate_p.h"
#include "qhistorystate.h"
#include "qhistorystate_p.h"
#include "qabstracttransition.h"
#include "qabstracttransition_p.h"
#include "qsignaltransition.h"
#include "qstatemachine.h"
#include "qstatemachine_p.h"
QT_BEGIN_NAMESPACE
/*!
\class QState
\brief The QState class provides a general-purpose state for QStateMachine.
\since 4.6
\ingroup statemachine
QState objects can have child states, and can have transitions to other
states. QState is part of \l{The State Machine Framework}.
The addTransition() function adds a transition. The removeTransition()
function removes a transition. The transitions() function returns the
state's outgoing transitions.
The assignProperty() function is used for defining property assignments that
should be performed when a state is entered.
Top-level states must be passed a QStateMachine object as their parent
state, or added to a state machine using QStateMachine::addState().
\section1 States with Child States
The childMode property determines how child states are treated. For
non-parallel state groups, the setInitialState() function must be called to
set the initial state. The child states are mutually exclusive states, and
the state machine needs to know which child state to enter when the parent
state is the target of a transition.
The state emits the QState::finished() signal when a final child state
(QFinalState) is entered.
The setErrorState() sets the state's error state. The error state is the
state that the state machine will transition to if an error is detected when
attempting to enter the state (e.g. because no initial state has been set).
*/
/*!
\property QState::initialState
\brief the initial state of this state (one of its child states)
*/
/*!
\property QState::errorState
\brief the error state of this state
*/
/*!
\property QState::childMode
\brief the child mode of this state
The default value of this property is QState::ExclusiveStates.
*/
/*!
\enum QState::ChildMode
This enum specifies how a state's child states are treated.
\value ExclusiveStates The child states are mutually exclusive and an
initial state must be set by calling QState::setInitialState().
\value ParallelStates The child states are parallel. When the parent state
is entered, all its child states are entered in parallel.
*/
QStatePrivate::QStatePrivate()
: QAbstractStatePrivate(StandardState),
errorState(0), initialState(0), childMode(QState::ExclusiveStates),
childStatesListNeedsRefresh(true), transitionsListNeedsRefresh(true)
{
}
QStatePrivate::~QStatePrivate()
{
}
void QStatePrivate::emitFinished()
{
Q_Q(QState);
emit q->finished();
}
void QStatePrivate::emitPropertiesAssigned()
{
Q_Q(QState);
emit q->propertiesAssigned();
}
/*!
Constructs a new state with the given \a parent state.
*/
QState::QState(QState *parent)
: QAbstractState(*new QStatePrivate, parent)
{
}
/*!
Constructs a new state with the given \a childMode and the given \a parent
state.
*/
QState::QState(ChildMode childMode, QState *parent)
: QAbstractState(*new QStatePrivate, parent)
{
Q_D(QState);
d->childMode = childMode;
}
/*!
\internal
*/
QState::QState(QStatePrivate &dd, QState *parent)
: QAbstractState(dd, parent)
{
}
/*!
Destroys this state.
*/
QState::~QState()
{
}
QList<QAbstractState*> QStatePrivate::childStates() const
{
if (childStatesListNeedsRefresh) {
childStatesList.clear();
QList<QObject*>::const_iterator it;
for (it = children.constBegin(); it != children.constEnd(); ++it) {
QAbstractState *s = qobject_cast<QAbstractState*>(*it);
if (!s || qobject_cast<QHistoryState*>(s))
continue;
childStatesList.append(s);
}
childStatesListNeedsRefresh = false;
}
return childStatesList;
}
QList<QHistoryState*> QStatePrivate::historyStates() const
{
QList<QHistoryState*> result;
QList<QObject*>::const_iterator it;
for (it = children.constBegin(); it != children.constEnd(); ++it) {
QHistoryState *h = qobject_cast<QHistoryState*>(*it);
if (h)
result.append(h);
}
return result;
}
QList<QAbstractTransition*> QStatePrivate::transitions() const
{
if (transitionsListNeedsRefresh) {
transitionsList.clear();
QList<QObject*>::const_iterator it;
for (it = children.constBegin(); it != children.constEnd(); ++it) {
QAbstractTransition *t = qobject_cast<QAbstractTransition*>(*it);
if (t)
transitionsList.append(t);
}
transitionsListNeedsRefresh = false;
}
return transitionsList;
}
#ifndef QT_NO_PROPERTIES
/*!
Instructs this state to set the property with the given \a name of the given
\a object to the given \a value when the state is entered.
\sa propertiesAssigned()
*/
void QState::assignProperty(QObject *object, const char *name,
const QVariant &value)
{
Q_D(QState);
if (!object) {
qWarning("QState::assignProperty: cannot assign property '%s' of null object", name);
return;
}
for (int i = 0; i < d->propertyAssignments.size(); ++i) {
QPropertyAssignment &assn = d->propertyAssignments[i];
if ((assn.object == object) && (assn.propertyName == name)) {
assn.value = value;
return;
}
}
d->propertyAssignments.append(QPropertyAssignment(object, name, value));
}
#endif // QT_NO_PROPERTIES
/*!
Returns this state's error state.
\sa QStateMachine::error()
*/
QAbstractState *QState::errorState() const
{
Q_D(const QState);
return d->errorState;
}
/*!
Sets this state's error state to be the given \a state. If the error state
is not set, or if it is set to 0, the state will inherit its parent's error
state recursively. If no error state is set for the state itself or any of
its ancestors, an error will cause the machine to stop executing and an error
will be printed to the console.
*/
void QState::setErrorState(QAbstractState *state)
{
Q_D(QState);
if (state != 0 && qobject_cast<QStateMachine*>(state)) {
qWarning("QStateMachine::setErrorState: root state cannot be error state");
return;
}
if (state != 0 && (!state->machine() || ((state->machine() != machine()) && !qobject_cast<QStateMachine*>(this)))) {
qWarning("QState::setErrorState: error state cannot belong "
"to a different state machine");
return;
}
d->errorState = state;
}
/*!
Adds the given \a transition. The transition has this state as the source.
This state takes ownership of the transition.
*/
void QState::addTransition(QAbstractTransition *transition)
{
Q_D(QState);
if (!transition) {
qWarning("QState::addTransition: cannot add null transition");
return ;
}
transition->setParent(this);
const QList<QWeakPointer<QAbstractState> > &targets = QAbstractTransitionPrivate::get(transition)->targetStates;
for (int i = 0; i < targets.size(); ++i) {
QAbstractState *t = targets.at(i).data();
if (!t) {
qWarning("QState::addTransition: cannot add transition to null state");
return ;
}
if ((QAbstractStatePrivate::get(t)->machine() != d->machine())
&& QAbstractStatePrivate::get(t)->machine() && d->machine()) {
qWarning("QState::addTransition: cannot add transition "
"to a state in a different state machine");
return ;
}
}
if (machine() != 0 && machine()->configuration().contains(this))
QStateMachinePrivate::get(machine())->registerTransitions(this);
}
/*!
Adds a transition associated with the given \a signal of the given \a sender
object, and returns the new QSignalTransition object. The transition has
this state as the source, and the given \a target as the target state.
*/
QSignalTransition *QState::addTransition(QObject *sender, const char *signal,
QAbstractState *target)
{
if (!sender) {
qWarning("QState::addTransition: sender cannot be null");
return 0;
}
if (!signal) {
qWarning("QState::addTransition: signal cannot be null");
return 0;
}
if (!target) {
qWarning("QState::addTransition: cannot add transition to null state");
return 0;
}
int offset = (*signal == '0'+QSIGNAL_CODE) ? 1 : 0;
const QMetaObject *meta = sender->metaObject();
if (meta->indexOfSignal(signal+offset) == -1) {
if (meta->indexOfSignal(QMetaObject::normalizedSignature(signal+offset)) == -1) {
qWarning("QState::addTransition: no such signal %s::%s",
meta->className(), signal+offset);
return 0;
}
}
QSignalTransition *trans = new QSignalTransition(sender, signal);
trans->setTargetState(target);
addTransition(trans);
return trans;
}
namespace {
// ### Make public?
class UnconditionalTransition : public QAbstractTransition
{
public:
UnconditionalTransition(QAbstractState *target)
: QAbstractTransition()
{ setTargetState(target); }
protected:
void onTransition(QEvent *) {}
bool eventTest(QEvent *) { return true; }
};
} // namespace
/*!
Adds an unconditional transition from this state to the given \a target
state, and returns then new transition object.
*/
QAbstractTransition *QState::addTransition(QAbstractState *target)
{
if (!target) {
qWarning("QState::addTransition: cannot add transition to null state");
return 0;
}
UnconditionalTransition *trans = new UnconditionalTransition(target);
addTransition(trans);
return trans;
}
/*!
Removes the given \a transition from this state. The state releases
ownership of the transition.
\sa addTransition()
*/
void QState::removeTransition(QAbstractTransition *transition)
{
Q_D(QState);
if (!transition) {
qWarning("QState::removeTransition: cannot remove null transition");
return;
}
if (transition->sourceState() != this) {
qWarning("QState::removeTransition: transition %p's source state (%p)"
" is different from this state (%p)",
transition, transition->sourceState(), this);
return;
}
QStateMachinePrivate *mach = QStateMachinePrivate::get(d->machine());
if (mach)
mach->unregisterTransition(transition);
transition->setParent(0);
}
/*!
\since 4.7
Returns this state's outgoing transitions (i.e. transitions where
this state is the \l{QAbstractTransition::sourceState()}{source
state}), or an empty list if this state has no outgoing transitions.
\sa addTransition()
*/
QList<QAbstractTransition*> QState::transitions() const
{
Q_D(const QState);
return d->transitions();
}
/*!
\reimp
*/
void QState::onEntry(QEvent *event)
{
Q_UNUSED(event);
}
/*!
\reimp
*/
void QState::onExit(QEvent *event)
{
Q_UNUSED(event);
}
/*!
Returns this state's initial state, or 0 if the state has no initial state.
*/
QAbstractState *QState::initialState() const
{
Q_D(const QState);
return d->initialState;
}
/*!
Sets this state's initial state to be the given \a state.
\a state has to be a child of this state.
*/
void QState::setInitialState(QAbstractState *state)
{
Q_D(QState);
if (d->childMode == QState::ParallelStates) {
qWarning("QState::setInitialState: ignoring attempt to set initial state "
"of parallel state group %p", this);
return;
}
if (state && (state->parentState() != this)) {
qWarning("QState::setInitialState: state %p is not a child of this state (%p)",
state, this);
return;
}
d->initialState = state;
}
/*!
Returns the child mode of this state.
*/
QState::ChildMode QState::childMode() const
{
Q_D(const QState);
return d->childMode;
}
/*!
Sets the child \a mode of this state.
*/
void QState::setChildMode(ChildMode mode)
{
Q_D(QState);
d->childMode = mode;
}
/*!
\reimp
*/
bool QState::event(QEvent *e)
{
Q_D(QState);
if ((e->type() == QEvent::ChildAdded) || (e->type() == QEvent::ChildRemoved)) {
d->childStatesListNeedsRefresh = true;
d->transitionsListNeedsRefresh = true;
}
return QAbstractState::event(e);
}
/*!
\fn QState::finished()
This signal is emitted when a final child state of this state is entered.
\sa QFinalState
*/
/*!
\fn QState::propertiesAssigned()
This signal is emitted when all properties have been assigned their final value. If the state
assigns a value to one or more properties for which an animation exists (either set on the
transition or as a default animation on the state machine), then the signal will not be emitted
until all such animations have finished playing.
If there are no relevant animations, or no property assignments defined for the state, then
the signal will be emitted immediately before the state is entered.
\sa QState::assignProperty(), QAbstractTransition::addAnimation()
*/
QT_END_NAMESPACE
#endif //QT_NO_STATEMACHINE
|