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39
40#include "qtimeline.h"
41
42#include <private/qobject_p.h>
43#include <QtCore/qcoreevent.h>
44#include <QtCore/qmath.h>
45#include <QtCore/qelapsedtimer.h>
46
47QT_BEGIN_NAMESPACE
48
49class QTimeLinePrivate : public QObjectPrivate
50{
51 Q_DECLARE_PUBLIC(QTimeLine)
52public:
53 inline QTimeLinePrivate()
54 : easingCurve(QEasingCurve::InOutSine),
55 startTime(0), duration(1000), startFrame(0), endFrame(0),
56 updateInterval(1000 / 25),
57 totalLoopCount(1), currentLoopCount(0), currentTime(0), timerId(0),
58 direction(QTimeLine::Forward),
59 state(QTimeLine::NotRunning)
60 { }
61
62 QElapsedTimer timer;
63 QEasingCurve easingCurve;
64
65 int startTime;
66 int duration;
67 int startFrame;
68 int endFrame;
69 int updateInterval;
70 int totalLoopCount;
71 int currentLoopCount;
72
73 int currentTime;
74 int timerId;
75
76 QTimeLine::Direction direction;
77 QTimeLine::State state;
78 inline void setState(QTimeLine::State newState)
79 {
80 Q_Q(QTimeLine);
81 if (newState != state)
82 emit q->stateChanged(newState: state = newState, QTimeLine::QPrivateSignal());
83 }
84
85 void setCurrentTime(int msecs);
86};
87
88/*!
89 \internal
90*/
91void QTimeLinePrivate::setCurrentTime(int msecs)
92{
93 Q_Q(QTimeLine);
94
95 qreal lastValue = q->currentValue();
96 int lastFrame = q->currentFrame();
97
98 // Determine if we are looping.
99 int elapsed = (direction == QTimeLine::Backward) ? (-msecs + duration) : msecs;
100 int loopCount = elapsed / duration;
101
102 bool looping = (loopCount != currentLoopCount);
103#ifdef QTIMELINE_DEBUG
104 qDebug() << "QTimeLinePrivate::setCurrentTime:" << msecs << duration << "with loopCount" << loopCount
105 << "currentLoopCount" << currentLoopCount
106 << "looping" << looping;
107#endif
108 if (looping)
109 currentLoopCount = loopCount;
110
111 // Normalize msecs to be between 0 and duration, inclusive.
112 currentTime = elapsed % duration;
113 if (direction == QTimeLine::Backward)
114 currentTime = duration - currentTime;
115
116 // Check if we have reached the end of loopcount.
117 bool finished = false;
118 if (totalLoopCount && currentLoopCount >= totalLoopCount) {
119 finished = true;
120 currentTime = (direction == QTimeLine::Backward) ? 0 : duration;
121 currentLoopCount = totalLoopCount - 1;
122 }
123
124 int currentFrame = q->frameForTime(msec: currentTime);
125#ifdef QTIMELINE_DEBUG
126 qDebug() << "QTimeLinePrivate::setCurrentTime: frameForTime" << currentTime << currentFrame;
127#endif
128 if (!qFuzzyCompare(p1: lastValue, p2: q->currentValue()))
129 emit q->valueChanged(x: q->currentValue(), QTimeLine::QPrivateSignal());
130 if (lastFrame != currentFrame) {
131 const int transitionframe = (direction == QTimeLine::Forward ? endFrame : startFrame);
132 if (looping && !finished && transitionframe != currentFrame) {
133#ifdef QTIMELINE_DEBUG
134 qDebug("QTimeLinePrivate::setCurrentTime: transitionframe");
135#endif
136 emit q->frameChanged(transitionframe, QTimeLine::QPrivateSignal());
137 }
138#ifdef QTIMELINE_DEBUG
139 else {
140 QByteArray reason;
141 if (!looping)
142 reason += " not looping";
143 if (finished) {
144 if (!reason.isEmpty())
145 reason += " and";
146 reason += " finished";
147 }
148 if (transitionframe == currentFrame) {
149 if (!reason.isEmpty())
150 reason += " and";
151 reason += " transitionframe is equal to currentFrame: " + QByteArray::number(currentFrame);
152 }
153 qDebug("QTimeLinePrivate::setCurrentTime: not transitionframe because %s", reason.constData());
154 }
155#endif
156 emit q->frameChanged(currentFrame, QTimeLine::QPrivateSignal());
157 }
158 if (finished && state == QTimeLine::Running) {
159 q->stop();
160 emit q->finished(QTimeLine::QPrivateSignal());
161 }
162}
163
164/*!
165 \class QTimeLine
166 \inmodule QtCore
167 \brief The QTimeLine class provides a timeline for controlling animations.
168 \since 4.2
169 \ingroup animation
170
171 It's most commonly used to animate a GUI control by calling a slot
172 periodically. You can construct a timeline by passing its duration in
173 milliseconds to QTimeLine's constructor. The timeline's duration describes
174 for how long the animation will run. Then you set a suitable frame range
175 by calling setFrameRange(). Finally connect the frameChanged() signal to a
176 suitable slot in the widget you wish to animate (for example, \l {QProgressBar::}{setValue()}
177 in QProgressBar). When you proceed to calling start(), QTimeLine will enter
178 Running state, and start emitting frameChanged() at regular intervals,
179 causing your widget's connected property's value to grow from the lower
180 end to the upper and of your frame range, at a steady rate. You can
181 specify the update interval by calling setUpdateInterval(). When done,
182 QTimeLine enters NotRunning state, and emits finished().
183
184 Example:
185
186 \snippet code/src_corelib_tools_qtimeline.cpp 0
187
188 By default the timeline runs once, from its beginning to its end,
189 upon which you must call start() again to restart from the beginning. To
190 make the timeline loop, you can call setLoopCount(), passing the number of
191 times the timeline should run before finishing. The direction can also be
192 changed, causing the timeline to run backward, by calling
193 setDirection(). You can also pause and unpause the timeline while it's
194 running by calling setPaused(). For interactive control, the
195 setCurrentTime() function is provided, which sets the time position of the
196 time line directly. Although most useful in NotRunning state (e.g.,
197 connected to a valueChanged() signal in a QSlider), this function can be
198 called at any time.
199
200 The frame interface is useful for standard widgets, but QTimeLine can be
201 used to control any type of animation. The heart of QTimeLine lies in the
202 valueForTime() function, which generates a \e value between 0 and 1 for a
203 given time. This value is typically used to describe the steps of an
204 animation, where 0 is the first step of an animation, and 1 is the last
205 step. When running, QTimeLine generates values between 0 and 1 by calling
206 valueForTime() and emitting valueChanged(). By default, valueForTime()
207 applies an interpolation algorithm to generate these value. You can choose
208 from a set of predefined timeline algorithms by calling setEasingCurve().
209
210 Note that, by default, QTimeLine uses QEasingCurve::InOutSine, which
211 provides a value that grows slowly, then grows steadily, and finally grows
212 slowly. For a custom timeline, you can reimplement valueForTime(), in which
213 case QTimeLine's easingCurve property is ignored.
214
215 \sa QProgressBar, QProgressDialog
216*/
217
218/*!
219 \enum QTimeLine::State
220
221 This enum describes the state of the timeline.
222
223 \value NotRunning The timeline is not running. This is the initial state
224 of QTimeLine, and the state QTimeLine reenters when finished. The current
225 time, frame and value remain unchanged until either setCurrentTime() is
226 called, or the timeline is started by calling start().
227
228 \value Paused The timeline is paused (i.e., temporarily
229 suspended). Calling setPaused(false) will resume timeline activity.
230
231 \value Running The timeline is running. While control is in the event
232 loop, QTimeLine will update its current time at regular intervals,
233 emitting valueChanged() and frameChanged() when appropriate.
234
235 \sa state(), stateChanged()
236*/
237
238/*!
239 \enum QTimeLine::Direction
240
241 This enum describes the direction of the timeline when in \l Running state.
242
243 \value Forward The current time of the timeline increases with time (i.e.,
244 moves from 0 and towards the end / duration).
245
246 \value Backward The current time of the timeline decreases with time (i.e.,
247 moves from the end / duration and towards 0).
248
249 \sa setDirection()
250*/
251
252/*!
253 \enum QTimeLine::CurveShape
254 \obsolete use QEasingCurve instead
255
256 This enum describes the shape of QTimeLine's value curve. The default shape
257 is EaseInOutCurve. The curve defines the relation between the value and the
258 timeline.
259
260 \value EaseInCurve Obsolete equivalent of QEasingCurve::InCurve
261 \value EaseOutCurve Obsolete equivalent of QEasingCurve::OutCurve
262 \value EaseInOutCurve Obsolete equivalent of QEasingCurve::InOutSine
263 \value LinearCurve Obsolete equivalent of QEasingCurve::Linear
264 \value SineCurve Obsolete equivalent of QEasingCurve::SineCurve
265 \value CosineCurve Obsolete equivalent of QEasingCurve::CosineCurve
266
267 \sa curveShape, setCurveShape(), easingCurve, QEasingCurve
268*/
269
270/*!
271 \fn void QTimeLine::valueChanged(qreal value)
272
273 QTimeLine emits this signal at regular intervals when in \l Running state,
274 but only if the current value changes. \a value is the current value. \a value is
275 a number between 0.0 and 1.0
276
277 \sa QTimeLine::setDuration(), QTimeLine::valueForTime(), QTimeLine::updateInterval
278*/
279
280/*!
281 \fn void QTimeLine::frameChanged(int frame)
282
283 QTimeLine emits this signal at regular intervals when in \l Running state,
284 but only if the current frame changes. \a frame is the current frame number.
285
286 \sa QTimeLine::setFrameRange(), QTimeLine::updateInterval
287*/
288
289/*!
290 \fn void QTimeLine::stateChanged(QTimeLine::State newState)
291
292 This signal is emitted whenever QTimeLine's state changes. The new state
293 is \a newState.
294*/
295
296/*!
297 \fn void QTimeLine::finished()
298
299 This signal is emitted when QTimeLine finishes (i.e., reaches the end of
300 its time line), and does not loop.
301*/
302
303/*!
304 Constructs a timeline with a duration of \a duration milliseconds. \a
305 parent is passed to QObject's constructor. The default duration is 1000
306 milliseconds.
307 */
308QTimeLine::QTimeLine(int duration, QObject *parent)
309 : QObject(*new QTimeLinePrivate, parent)
310{
311 setDuration(duration);
312}
313
314/*!
315 Destroys the timeline.
316 */
317QTimeLine::~QTimeLine()
318{
319 Q_D(QTimeLine);
320
321 if (d->state == Running)
322 stop();
323}
324
325/*!
326 Returns the state of the timeline.
327
328 \sa start(), setPaused(), stop()
329*/
330QTimeLine::State QTimeLine::state() const
331{
332 Q_D(const QTimeLine);
333 return d->state;
334}
335
336/*!
337 \property QTimeLine::loopCount
338 \brief the number of times the timeline should loop before it's finished.
339
340 A loop count of of 0 means that the timeline will loop forever.
341
342 By default, this property contains a value of 1.
343*/
344int QTimeLine::loopCount() const
345{
346 Q_D(const QTimeLine);
347 return d->totalLoopCount;
348}
349void QTimeLine::setLoopCount(int count)
350{
351 Q_D(QTimeLine);
352 d->totalLoopCount = count;
353}
354
355/*!
356 \property QTimeLine::direction
357 \brief the direction of the timeline when QTimeLine is in \l Running
358 state.
359
360 This direction indicates whether the time moves from 0 towards the
361 timeline duration, or from the value of the duration and towards 0 after
362 start() has been called.
363
364 By default, this property is set to \l Forward.
365*/
366QTimeLine::Direction QTimeLine::direction() const
367{
368 Q_D(const QTimeLine);
369 return d->direction;
370}
371void QTimeLine::setDirection(Direction direction)
372{
373 Q_D(QTimeLine);
374 d->direction = direction;
375 d->startTime = d->currentTime;
376 d->timer.start();
377}
378
379/*!
380 \property QTimeLine::duration
381 \brief the total duration of the timeline in milliseconds.
382
383 By default, this value is 1000 (i.e., 1 second), but you can change this
384 by either passing a duration to QTimeLine's constructor, or by calling
385 setDuration(). The duration must be larger than 0.
386
387 \note Changing the duration does not cause the current time to be reset
388 to zero or the new duration. You also need to call setCurrentTime() with
389 the desired value.
390*/
391int QTimeLine::duration() const
392{
393 Q_D(const QTimeLine);
394 return d->duration;
395}
396void QTimeLine::setDuration(int duration)
397{
398 Q_D(QTimeLine);
399 if (duration <= 0) {
400 qWarning(msg: "QTimeLine::setDuration: cannot set duration <= 0");
401 return;
402 }
403 d->duration = duration;
404}
405
406/*!
407 Returns the start frame, which is the frame corresponding to the start of
408 the timeline (i.e., the frame for which the current value is 0).
409
410 \sa setStartFrame(), setFrameRange()
411*/
412int QTimeLine::startFrame() const
413{
414 Q_D(const QTimeLine);
415 return d->startFrame;
416}
417
418/*!
419 Sets the start frame, which is the frame corresponding to the start of the
420 timeline (i.e., the frame for which the current value is 0), to \a frame.
421
422 \sa startFrame(), endFrame(), setFrameRange()
423*/
424void QTimeLine::setStartFrame(int frame)
425{
426 Q_D(QTimeLine);
427 d->startFrame = frame;
428}
429
430/*!
431 Returns the end frame, which is the frame corresponding to the end of the
432 timeline (i.e., the frame for which the current value is 1).
433
434 \sa setEndFrame(), setFrameRange()
435*/
436int QTimeLine::endFrame() const
437{
438 Q_D(const QTimeLine);
439 return d->endFrame;
440}
441
442/*!
443 Sets the end frame, which is the frame corresponding to the end of the
444 timeline (i.e., the frame for which the current value is 1), to \a frame.
445
446 \sa endFrame(), startFrame(), setFrameRange()
447*/
448void QTimeLine::setEndFrame(int frame)
449{
450 Q_D(QTimeLine);
451 d->endFrame = frame;
452}
453
454/*!
455 Sets the timeline's frame counter to start at \a startFrame, and end and
456 \a endFrame. For each time value, QTimeLine will find the corresponding
457 frame when you call currentFrame() or frameForTime() by interpolating,
458 using the return value of valueForTime().
459
460 When in Running state, QTimeLine also emits the frameChanged() signal when
461 the frame changes.
462
463 \sa startFrame(), endFrame(), start(), currentFrame()
464*/
465void QTimeLine::setFrameRange(int startFrame, int endFrame)
466{
467 Q_D(QTimeLine);
468 d->startFrame = startFrame;
469 d->endFrame = endFrame;
470}
471
472/*!
473 \property QTimeLine::updateInterval
474 \brief the time in milliseconds between each time QTimeLine updates its
475 current time.
476
477 When updating the current time, QTimeLine will emit valueChanged() if the
478 current value changed, and frameChanged() if the frame changed.
479
480 By default, the interval is 40 ms, which corresponds to a rate of 25
481 updates per second.
482*/
483int QTimeLine::updateInterval() const
484{
485 Q_D(const QTimeLine);
486 return d->updateInterval;
487}
488void QTimeLine::setUpdateInterval(int interval)
489{
490 Q_D(QTimeLine);
491 d->updateInterval = interval;
492}
493
494#if QT_DEPRECATED_SINCE(5, 15)
495/*!
496 \property QTimeLine::curveShape
497 \brief the shape of the timeline curve.
498
499 The curve shape describes the relation between the time and value for the
500 base implementation of valueForTime().
501
502 This property is an indirect way to update the easingCurve property; if you
503 set both, the one set more recently overrides the other. (If valueForTime()
504 is reimplemented it will override both.)
505
506 By default, this property is set to \l EaseInOutCurve.
507
508 \obsolete Access \c easingCurve instead.
509
510 \sa valueForTime(), easingCurve
511*/
512QTimeLine::CurveShape QTimeLine::curveShape() const
513{
514 Q_D(const QTimeLine);
515 switch (d->easingCurve.type()) {
516 default:
517 case QEasingCurve::InOutSine:
518 return EaseInOutCurve;
519 case QEasingCurve::InCurve:
520 return EaseInCurve;
521 case QEasingCurve::OutCurve:
522 return EaseOutCurve;
523 case QEasingCurve::Linear:
524 return LinearCurve;
525 case QEasingCurve::SineCurve:
526 return SineCurve;
527 case QEasingCurve::CosineCurve:
528 return CosineCurve;
529 }
530 return EaseInOutCurve;
531}
532
533static QEasingCurve::Type convert(QTimeLine::CurveShape shape)
534{
535 switch (shape) {
536#define CASE(x, y) case QTimeLine::x: return QEasingCurve::y
537 CASE(EaseInOutCurve, InOutSine);
538 CASE(EaseInCurve, InCurve);
539 CASE(EaseOutCurve, OutCurve);
540 CASE(LinearCurve, Linear);
541 CASE(SineCurve, SineCurve);
542 CASE(CosineCurve, CosineCurve);
543#undef CASE
544 }
545 Q_UNREACHABLE();
546}
547
548void QTimeLine::setCurveShape(CurveShape shape)
549{
550 setEasingCurve(convert(shape));
551}
552#endif // 5.15 deprecation
553
554/*!
555 \property QTimeLine::easingCurve
556
557 \since 4.6
558
559 Specifies the easing curve that the timeline will use.
560 If valueForTime() is reimplemented, this value is ignored.
561 If both easingCurve and curveShape are set, the last property set will
562 override the previous one.
563
564 \sa valueForTime()
565*/
566
567QEasingCurve QTimeLine::easingCurve() const
568{
569 Q_D(const QTimeLine);
570 return d->easingCurve;
571}
572
573void QTimeLine::setEasingCurve(const QEasingCurve& curve)
574{
575 Q_D(QTimeLine);
576 d->easingCurve = curve;
577}
578
579/*!
580 \property QTimeLine::currentTime
581 \brief the current time of the time line.
582
583 When QTimeLine is in Running state, this value is updated continuously as
584 a function of the duration and direction of the timeline. Otherwise, it is
585 value that was current when stop() was called last, or the value set by
586 setCurrentTime().
587
588 By default, this property contains a value of 0.
589*/
590int QTimeLine::currentTime() const
591{
592 Q_D(const QTimeLine);
593 return d->currentTime;
594}
595void QTimeLine::setCurrentTime(int msec)
596{
597 Q_D(QTimeLine);
598 d->startTime = 0;
599 d->currentLoopCount = 0;
600 d->timer.restart();
601 d->setCurrentTime(msec);
602}
603
604/*!
605 Returns the frame corresponding to the current time.
606
607 \sa currentTime(), frameForTime(), setFrameRange()
608*/
609int QTimeLine::currentFrame() const
610{
611 Q_D(const QTimeLine);
612 return frameForTime(msec: d->currentTime);
613}
614
615/*!
616 Returns the value corresponding to the current time.
617
618 \sa valueForTime(), currentFrame()
619*/
620qreal QTimeLine::currentValue() const
621{
622 Q_D(const QTimeLine);
623 return valueForTime(msec: d->currentTime);
624}
625
626/*!
627 Returns the frame corresponding to the time \a msec. This value is
628 calculated using a linear interpolation of the start and end frame, based
629 on the value returned by valueForTime().
630
631 \sa valueForTime(), setFrameRange()
632*/
633int QTimeLine::frameForTime(int msec) const
634{
635 Q_D(const QTimeLine);
636 if (d->direction == Forward)
637 return d->startFrame + int((d->endFrame - d->startFrame) * valueForTime(msec));
638 return d->startFrame + qCeil(v: (d->endFrame - d->startFrame) * valueForTime(msec));
639}
640
641/*!
642 Returns the timeline value for the time \a msec. The returned value, which
643 varies depending on the curve shape, is always between 0 and 1. If \a msec
644 is 0, the default implementation always returns 0.
645
646 Reimplement this function to provide a custom curve shape for your
647 timeline.
648
649 \sa CurveShape, frameForTime()
650*/
651qreal QTimeLine::valueForTime(int msec) const
652{
653 Q_D(const QTimeLine);
654 msec = qMin(a: qMax(a: msec, b: 0), b: d->duration);
655
656 qreal value = msec / qreal(d->duration);
657 return d->easingCurve.valueForProgress(progress: value);
658}
659
660/*!
661 Starts the timeline. QTimeLine will enter Running state, and once it
662 enters the event loop, it will update its current time, frame and value at
663 regular intervals. The default interval is 40 ms (i.e., 25 times per
664 second). You can change the update interval by calling
665 setUpdateInterval().
666
667 The timeline will start from position 0, or the end if going backward.
668 If you want to resume a stopped timeline without restarting, you can call
669 resume() instead.
670
671 \sa resume(), updateInterval(), frameChanged(), valueChanged()
672*/
673void QTimeLine::start()
674{
675 Q_D(QTimeLine);
676 if (d->timerId) {
677 qWarning(msg: "QTimeLine::start: already running");
678 return;
679 }
680 int curTime = 0;
681 if (d->direction == Backward)
682 curTime = d->duration;
683 d->timerId = startTimer(interval: d->updateInterval);
684 d->startTime = curTime;
685 d->currentLoopCount = 0;
686 d->timer.start();
687 d->setState(Running);
688 d->setCurrentTime(curTime);
689}
690
691/*!
692 Resumes the timeline from the current time. QTimeLine will reenter Running
693 state, and once it enters the event loop, it will update its current time,
694 frame and value at regular intervals.
695
696 In contrast to start(), this function does not restart the timeline before
697 it resumes.
698
699 \sa start(), updateInterval(), frameChanged(), valueChanged()
700*/
701void QTimeLine::resume()
702{
703 Q_D(QTimeLine);
704 if (d->timerId) {
705 qWarning(msg: "QTimeLine::resume: already running");
706 return;
707 }
708 d->timerId = startTimer(interval: d->updateInterval);
709 d->startTime = d->currentTime;
710 d->timer.start();
711 d->setState(Running);
712}
713
714/*!
715 Stops the timeline, causing QTimeLine to enter NotRunning state.
716
717 \sa start()
718*/
719void QTimeLine::stop()
720{
721 Q_D(QTimeLine);
722 if (d->timerId)
723 killTimer(id: d->timerId);
724 d->setState(NotRunning);
725 d->timerId = 0;
726}
727
728/*!
729 If \a paused is true, the timeline is paused, causing QTimeLine to enter
730 Paused state. No updates will be signaled until either start() or
731 setPaused(false) is called. If \a paused is false, the timeline is resumed
732 and continues where it left.
733
734 \sa state(), start()
735*/
736void QTimeLine::setPaused(bool paused)
737{
738 Q_D(QTimeLine);
739 if (d->state == NotRunning) {
740 qWarning(msg: "QTimeLine::setPaused: Not running");
741 return;
742 }
743 if (paused && d->state != Paused) {
744 d->startTime = d->currentTime;
745 killTimer(id: d->timerId);
746 d->timerId = 0;
747 d->setState(Paused);
748 } else if (!paused && d->state == Paused) {
749 // Same as resume()
750 d->timerId = startTimer(interval: d->updateInterval);
751 d->startTime = d->currentTime;
752 d->timer.start();
753 d->setState(Running);
754 }
755}
756
757/*!
758 Toggles the direction of the timeline. If the direction was Forward, it
759 becomes Backward, and vice verca.
760
761 \sa setDirection()
762*/
763void QTimeLine::toggleDirection()
764{
765 Q_D(QTimeLine);
766 setDirection(d->direction == Forward ? Backward : Forward);
767}
768
769/*!
770 \reimp
771*/
772void QTimeLine::timerEvent(QTimerEvent *event)
773{
774 Q_D(QTimeLine);
775 if (event->timerId() != d->timerId) {
776 event->ignore();
777 return;
778 }
779 event->accept();
780
781 if (d->direction == Forward) {
782 d->setCurrentTime(d->startTime + d->timer.elapsed());
783 } else {
784 d->setCurrentTime(d->startTime - d->timer.elapsed());
785 }
786}
787
788QT_END_NAMESPACE
789
790#include "moc_qtimeline.cpp"
791

source code of qtbase/src/corelib/tools/qtimeline.cpp