Make Media::Clip::Playback independent of slider.

Now animation of the playback progress is processed inside the
Media::Clip::Playback and the sliders just hold plain float64 value.

Telegram/SourceFiles/media/player/media_player_cover.cpp

@@ -72,7 +72,8 @@ CoverWidget::CoverWidget(QWidget *parent) : TWidget(parent)
 , _nameLabel(this, st::mediaPlayerName)
 , _timeLabel(this, st::mediaPlayerTime)
 , _close(this, st::mediaPlayerPanelClose)
-, _playback(std::make_unique<Clip::Playback>(new Ui::MediaSlider(this, st::mediaPlayerPanelPlayback)))
+, _playbackSlider(this, st::mediaPlayerPanelPlayback)
+, _playback(std::make_unique<Clip::Playback>())
 , _playPause(this)
 , _volumeToggle(this, st::mediaPlayerVolumeToggle)
 , _volumeController(this)
@@ -86,11 +87,19 @@ CoverWidget::CoverWidget(QWidget *parent) : TWidget(parent)
 	_timeLabel->setAttribute(Qt::WA_TransparentForMouseEvents);
 	setMouseTracking(true);
 
-	_playback->setChangeProgressCallback([this](float64 value) {
+	_playback->setInLoadingStateChangedCallback([this](bool loading) {
-		handleSeekProgress(value);
+		_playbackSlider->setDisabled(loading);
 	});
-	_playback->setChangeFinishedCallback([this](float64 value) {
+	_playback->setValueChangedCallback([this](float64 value) {
+		_playbackSlider->setValue(value);
+	});
+	_playbackSlider->setChangeProgressCallback([this](float64 value) {
+		handleSeekProgress(value);
+		_playback->setValue(value, false);
+	});
+	_playbackSlider->setChangeFinishedCallback([this](float64 value) {
 		handleSeekFinished(value);
+		_playback->setValue(value, false);
 	});
 	_playPause->setClickedCallback([this] {
 		instance()->playPauseCancelClicked();
@@ -168,7 +177,7 @@ void CoverWidget::resizeEvent(QResizeEvent *e) {
 
 	int skip = (st::mediaPlayerPanelPlayback.seekSize.width() / 2);
 	int length = (width() - 2 * st::mediaPlayerPanelPadding + st::mediaPlayerPanelPlayback.seekSize.width());
-	_playback->setGeometry(st::mediaPlayerPanelPadding - skip, st::mediaPlayerPanelPlaybackTop, length, 2 * st::mediaPlayerPanelPlaybackPadding + st::mediaPlayerPanelPlayback.width);
+	_playbackSlider->setGeometry(st::mediaPlayerPanelPadding - skip, st::mediaPlayerPanelPlaybackTop, length, 2 * st::mediaPlayerPanelPlaybackPadding + st::mediaPlayerPanelPlayback.width);
 
 	auto top = st::mediaPlayerPanelVolumeToggleTop;
 	auto right = st::mediaPlayerPanelPlayLeft;
@@ -269,11 +278,11 @@ void CoverWidget::updateTimeText(const TrackState &state) {
 
 	if (state.id.audio()->loading()) {
 		_time = QString::number(qRound(state.id.audio()->progress() * 100)) + '%';
-		_playback->setDisabled(true);
+		_playbackSlider->setDisabled(true);
 	} else {
 		display = display / frequency;
 		_time = formatDurationText(display);
-		_playback->setDisabled(false);
+		_playbackSlider->setDisabled(false);
 	}
 	if (_seekPositionMs < 0) {
 		updateTimeLabel();

Telegram/SourceFiles/media/player/media_player_cover.h

@@ -26,6 +26,7 @@ namespace Ui {
 class FlatLabel;
 class LabelSimple;
 class IconButton;
+class MediaSlider;
 } // namespace Ui
 
 namespace Media {
@@ -80,6 +81,7 @@ private:
 	object_ptr<Ui::FlatLabel> _nameLabel;
 	object_ptr<Ui::LabelSimple> _timeLabel;
 	object_ptr<Ui::IconButton> _close;
+	object_ptr<Ui::MediaSlider> _playbackSlider;
 	std::unique_ptr<Clip::Playback> _playback;
 	object_ptr<Ui::IconButton> _previousTrack = { nullptr };
 	object_ptr<PlayButton> _playPause;

Telegram/SourceFiles/media/player/media_player_volume_controller.cpp

@@ -45,12 +45,10 @@ VolumeController::VolumeController(QWidget *parent) : TWidget(parent)
 	});
 	subscribe(Global::RefSongVolumeChanged(), [this] {
 		if (!_slider->isChanging()) {
-			_slider->setValue(Global::SongVolume(), true);
+			_slider->setValue(Global::SongVolume());
 		}
 	});
-
+	setVolume(Global::SongVolume());
-	auto animated = false;
-	setVolume(Global::SongVolume(), animated);
 
 	resize(st::mediaPlayerPanelVolumeWidth, 2 * st::mediaPlayerPanelPlaybackPadding + st::mediaPlayerPanelPlayback.width);
 }
@@ -65,8 +63,8 @@ void VolumeController::resizeEvent(QResizeEvent *e) {
 	_slider->setGeometry(rect());
 }
 
-void VolumeController::setVolume(float64 volume, bool animated) {
+void VolumeController::setVolume(float64 volume) {
-	_slider->setValue(volume, animated);
+	_slider->setValue(volume);
 	if (volume > 0) {
 		Global::SetRememberedSongVolume(volume);
 	}

Telegram/SourceFiles/media/player/media_player_volume_controller.h

@@ -38,7 +38,7 @@ protected:
 	void resizeEvent(QResizeEvent *e) override;
 
 private:
-	void setVolume(float64 volume, bool animated = true);
+	void setVolume(float64 volume);
 	void applyVolumeChange(float64 volume);
 
 	object_ptr<Ui::MediaSlider> _slider;

Telegram/SourceFiles/media/player/media_player_widget.cpp

@@ -91,7 +91,8 @@ Widget::Widget(QWidget *parent) : TWidget(parent)
 , _repeatTrack(this, st::mediaPlayerRepeatButton)
 , _close(this, st::mediaPlayerClose)
 , _shadow(this, st::shadowFg)
-, _playback(std::make_unique<Clip::Playback>(new Ui::FilledSlider(this, st::mediaPlayerPlayback))) {
+, _playbackSlider(this, st::mediaPlayerPlayback)
+, _playback(std::make_unique<Clip::Playback>()) {
 	setAttribute(Qt::WA_OpaquePaintEvent);
 	setMouseTracking(true);
 	resize(width(), st::mediaPlayerHeight + st::lineWidth);
@@ -99,11 +100,19 @@ Widget::Widget(QWidget *parent) : TWidget(parent)
 	_nameLabel->setAttribute(Qt::WA_TransparentForMouseEvents);
 	_timeLabel->setAttribute(Qt::WA_TransparentForMouseEvents);
 
-	_playback->setChangeProgressCallback([this](float64 value) {
+	_playback->setInLoadingStateChangedCallback([this](bool loading) {
-		handleSeekProgress(value);
+		_playbackSlider->setDisabled(loading);
 	});
-	_playback->setChangeFinishedCallback([this](float64 value) {
+	_playback->setValueChangedCallback([this](float64 value) {
+		_playbackSlider->setValue(value);
+	});
+	_playbackSlider->setChangeProgressCallback([this](float64 value) {
+		handleSeekProgress(value);
+		_playback->setValue(value, false);
+	});
+	_playbackSlider->setChangeFinishedCallback([this](float64 value) {
 		handleSeekFinished(value);
+		_playback->setValue(value, false);
 	});
 	_playPause->setClickedCallback([this] {
 		instance()->playPauseCancelClicked();
@@ -167,12 +176,12 @@ void Widget::setShadowGeometryToLeft(int x, int y, int w, int h) {
 
 void Widget::showShadow() {
 	_shadow->show();
-	_playback->show();
+	_playbackSlider->show();
 }
 
 void Widget::hideShadow() {
 	_shadow->hide();
-	_playback->hide();
+	_playbackSlider->hide();
 }
 
 QPoint Widget::getPositionForVolumeWidget() const {
@@ -223,7 +232,7 @@ void Widget::resizeEvent(QResizeEvent *e) {
 
 	updatePlayPrevNextPositions();
 
-	_playback->setGeometry(0, height() - st::mediaPlayerPlayback.fullWidth, width(), st::mediaPlayerPlayback.fullWidth);
+	_playbackSlider->setGeometry(0, height() - st::mediaPlayerPlayback.fullWidth, width(), st::mediaPlayerPlayback.fullWidth);
 }
 
 void Widget::paintEvent(QPaintEvent *e) {
@@ -346,11 +355,11 @@ void Widget::updateTimeText(const TrackState &state) {
 
 	if (state.id.audio()->loading()) {
 		_time = QString::number(qRound(state.id.audio()->progress() * 100)) + '%';
-		_playback->setDisabled(true);
+		_playbackSlider->setDisabled(true);
 	} else {
 		display = display / frequency;
 		_time = formatDurationText(display);
-		_playback->setDisabled(false);
+		_playbackSlider->setDisabled(false);
 	}
 	if (_seekPositionMs < 0) {
 		updateTimeLabel();

Telegram/SourceFiles/media/player/media_player_widget.h

@@ -27,6 +27,7 @@ class FlatLabel;
 class LabelSimple;
 class IconButton;
 class PlainShadow;
+class FilledSlider;
 } // namespace Ui
 
 namespace Media {
@@ -101,6 +102,7 @@ private:
 	object_ptr<Ui::IconButton> _repeatTrack;
 	object_ptr<Ui::IconButton> _close;
 	object_ptr<Ui::PlainShadow> _shadow = { nullptr };
+	object_ptr<Ui::FilledSlider> _playbackSlider;
 	std::unique_ptr<Clip::Playback> _playback;
 
 };

Telegram/SourceFiles/media/view/media_clip_controller.cpp

@@ -34,7 +34,8 @@ namespace Clip {
 
 Controller::Controller(QWidget *parent) : TWidget(parent)
 , _playPauseResume(this, st::mediaviewPlayButton)
-, _playback(std::make_unique<Playback>(new Ui::MediaSlider(this, st::mediaviewPlayback)))
+, _playbackSlider(this, st::mediaviewPlayback)
+, _playback(std::make_unique<Playback>())
 , _volumeController(this)
 , _fullScreenToggle(this, st::mediaviewFullScreenButton)
 , _playedAlready(this, st::mediaviewPlayProgressLabel)
@@ -50,11 +51,19 @@ Controller::Controller(QWidget *parent) : TWidget(parent)
 	connect(_fullScreenToggle, SIGNAL(clicked()), this, SIGNAL(toFullScreenPressed()));
 	connect(_volumeController, SIGNAL(volumeChanged(float64)), this, SIGNAL(volumeChanged(float64)));
 
-	_playback->setChangeProgressCallback([this](float64 value) {
+	_playback->setInLoadingStateChangedCallback([this](bool loading) {
-		handleSeekProgress(value);
+		_playbackSlider->setDisabled(loading);
 	});
-	_playback->setChangeFinishedCallback([this](float64 value) {
+	_playback->setValueChangedCallback([this](float64 value) {
+		_playbackSlider->setValue(value);
+	});
+	_playbackSlider->setChangeProgressCallback([this](float64 value) {
+		handleSeekProgress(value);
+		_playback->setValue(value, false);
+	});
+	_playbackSlider->setChangeFinishedCallback([this](float64 value) {
 		handleSeekFinished(value);
+		_playback->setValue(value, false);
 	});
 }
 
@@ -93,7 +102,7 @@ void Controller::hideAnimated() {
 template <typename Callback>
 void Controller::startFading(Callback start) {
 	start();
-	_playback->show();
+	_playbackSlider->show();
 }
 
 void Controller::fadeFinished() {
@@ -101,7 +110,7 @@ void Controller::fadeFinished() {
 }
 
 void Controller::fadeUpdated(float64 opacity) {
-	_playback->setFadeOpacity(opacity);
+	_playbackSlider->setFadeOpacity(opacity);
 }
 
 void Controller::updatePlayback(const Player::TrackState &state) {
@@ -178,12 +187,12 @@ void Controller::setInFullScreen(bool inFullScreen) {
 
 void Controller::grabStart() {
 	showChildren();
-	_playback->hide();
+	_playbackSlider->hide();
 }
 
 void Controller::grabFinish() {
 	hideChildren();
-	_playback->show();
+	_playbackSlider->show();
 }
 
 void Controller::resizeEvent(QResizeEvent *e) {
@@ -195,9 +204,9 @@ void Controller::resizeEvent(QResizeEvent *e) {
 
 	_volumeController->moveToRight(st::mediaviewFullScreenLeft + _fullScreenToggle->width() + st::mediaviewVolumeLeft, (height() - _volumeController->height()) / 2);
 
-	int playbackWidth = width() - st::mediaviewPlayPauseLeft - _playPauseResume->width() - playTop - fullScreenTop - _volumeController->width() - st::mediaviewVolumeLeft - _fullScreenToggle->width() - st::mediaviewFullScreenLeft;
+	auto playbackWidth = width() - st::mediaviewPlayPauseLeft - _playPauseResume->width() - playTop - fullScreenTop - _volumeController->width() - st::mediaviewVolumeLeft - _fullScreenToggle->width() - st::mediaviewFullScreenLeft;
-	_playback->resize(playbackWidth, st::mediaviewPlayback.seekSize.height());
+	_playbackSlider->resize(playbackWidth, st::mediaviewPlayback.seekSize.height());
-	_playback->moveToLeft(st::mediaviewPlayPauseLeft + _playPauseResume->width() + playTop, st::mediaviewPlaybackTop);
+	_playbackSlider->moveToLeft(st::mediaviewPlayPauseLeft + _playPauseResume->width() + playTop, st::mediaviewPlaybackTop);
 
 	_playedAlready->moveToLeft(st::mediaviewPlayPauseLeft + _playPauseResume->width() + playTop, st::mediaviewPlayProgressTop);
 	_toPlayLeft->moveToRight(width() - (st::mediaviewPlayPauseLeft + _playPauseResume->width() + playTop) - playbackWidth, st::mediaviewPlayProgressTop);

Telegram/SourceFiles/media/view/media_clip_controller.h

@@ -24,6 +24,7 @@ namespace Ui {
 class LabelSimple;
 class FadeAnimation;
 class IconButton;
+class MediaSlider;
 } // namespace Ui
 
 namespace Media {
@@ -86,6 +87,7 @@ private:
 	TimeMs _lastDurationMs = 0;
 
 	object_ptr<Ui::IconButton> _playPauseResume;
+	object_ptr<Ui::MediaSlider> _playbackSlider;
 	std::unique_ptr<Playback> _playback;
 	object_ptr<VolumeController> _volumeController;
 	object_ptr<Ui::IconButton> _fullScreenToggle;

Telegram/SourceFiles/media/view/media_clip_playback.cpp

@@ -26,14 +26,19 @@ Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
 namespace Media {
 namespace Clip {
 
-Playback::Playback(Ui::ContinuousSlider *slider) : _slider(slider) {
+Playback::Playback() : _a_value(animation(this, &Playback::step_value)) {
 }
 
 void Playback::updateState(const Player::TrackState &state) {
 	qint64 position = 0, length = state.length;
 
-	auto wasDisabled = _slider->isDisabled();
+	auto wasInLoadingState = _inLoadingState;
-	if (wasDisabled) setDisabled(false);
+	if (wasInLoadingState) {
+		_inLoadingState = false;
+		if (_inLoadingStateChanged) {
+			_inLoadingStateChanged(false);
+		}
+	}
 
 	_playing = !Player::IsStopped(state.state);
 	if (_playing || state.state == Player::State::Stopped) {
@@ -44,25 +49,60 @@ void Playback::updateState(const Player::TrackState &state) {
 		position = 0;
 	}
 
-	float64 progress = 0.;
+	auto progress = 0.;
 	if (position > length) {
 		progress = 1.;
 	} else if (length) {
 		progress = length ? snap(float64(position) / length, 0., 1.) : 0.;
 	}
-	if (length != _length || position != _position || wasDisabled) {
+	if (length != _length || position != _position || wasInLoadingState) {
-		auto animated = (length && _length&& progress > _slider->value());
+		auto animated = (length && _length && progress > value());
-		_slider->setValue(progress, animated);
+		setValue(progress, animated);
 		_position = position;
 		_length = length;
 	}
-	_slider->update();
 }
 
 void Playback::updateLoadingState(float64 progress) {
-	setDisabled(true);
+	if (!_inLoadingState) {
-	auto animated = progress > _slider->value();
+		_inLoadingState = true;
-	_slider->setValue(progress, animated);
+		if (_inLoadingStateChanged) {
+			_inLoadingStateChanged(true);
+		}
+	}
+	auto animated = (progress > value());
+	setValue(progress, animated);
+}
+
+
+float64 Playback::value() const {
+	return a_value.current();
+}
+
+void Playback::setValue(float64 value, bool animated) {
+	if (animated) {
+		a_value.start(value);
+		_a_value.start();
+	} else {
+		a_value = anim::value(value, value);
+		_a_value.stop();
+	}
+	if (_valueChanged) {
+		_valueChanged(a_value.current());
+	}
+}
+
+void Playback::step_value(float64 ms, bool timer) {
+	auto dt = ms / (2 * AudioVoiceMsgUpdateView);
+	if (dt >= 1) {
+		_a_value.stop();
+		a_value.finish();
+	} else {
+		a_value.update(qMin(dt, 1.), anim::linear);
+	}
+	if (timer && _valueChanged) {
+		_valueChanged(a_value.current());
+	}
 }
 
 } // namespace Clip

Telegram/SourceFiles/media/view/media_clip_playback.h

@@ -31,41 +31,31 @@ namespace Clip {
 
 class Playback {
 public:
-	Playback(Ui::ContinuousSlider *slider);
+	Playback();
+
+	void setValueChangedCallback(base::lambda<void(float64)> callback) {
+		_valueChanged = std::move(callback);
+	}
+	void setInLoadingStateChangedCallback(base::lambda<void(bool)> callback) {
+		_inLoadingStateChanged = std::move(callback);
+	}
+	void setValue(float64 value, bool animated);
 
 	void updateState(const Player::TrackState &state);
 	void updateLoadingState(float64 progress);
 
-	void setFadeOpacity(float64 opacity) {
-		_slider->setFadeOpacity(opacity);
-	}
-	void setChangeProgressCallback(Ui::ContinuousSlider::Callback &&callback) {
-		_slider->setChangeProgressCallback(std::move(callback));
-	}
-	void setChangeFinishedCallback(Ui::ContinuousSlider::Callback &&callback) {
-		_slider->setChangeFinishedCallback(std::move(callback));
-	}
-	void setGeometry(int x, int y, int w, int h) {
-		_slider->setGeometry(x, y, w, h);
-	}
-	void hide() {
-		_slider->hide();
-	}
-	void show() {
-		_slider->show();
-	}
-	void moveToLeft(int x, int y) {
-		_slider->moveToLeft(x, y);
-	}
-	void resize(int w, int h) {
-		_slider->resize(w, h);
-	}
-	void setDisabled(bool disabled) {
-		_slider->setDisabled(disabled);
-	}
-
 private:
-	Ui::ContinuousSlider *_slider;
+	float64 value() const;
+	void step_value(float64 ms, bool timer);
+
+	// This can animate for a very long time (like in music playing),
+	// so it should be a BasicAnimation, not an Animation.
+	anim::value a_value;
+	BasicAnimation _a_value;
+	base::lambda<void(float64)> _valueChanged;
+
+	bool _inLoadingState = false;
+	base::lambda<void(bool)> _inLoadingStateChanged;
 
 	int64 _position = 0;
 	int64 _length = 0;

Telegram/SourceFiles/ui/widgets/continuous_sliders.cpp

@@ -27,15 +27,10 @@ constexpr auto kByWheelFinishedTimeout = 1000;
 
 } // namespace
 
-ContinuousSlider::ContinuousSlider(QWidget *parent) : TWidget(parent)
+ContinuousSlider::ContinuousSlider(QWidget *parent) : TWidget(parent) {
-, _a_value(animation(this, &ContinuousSlider::step_value)) {
 	setCursor(style::cur_pointer);
 }
 
-float64 ContinuousSlider::value() const {
-	return a_value.current();
-}
-
 void ContinuousSlider::setDisabled(bool disabled) {
 	if (_disabled != disabled) {
 		_disabled = disabled;
@@ -50,7 +45,7 @@ void ContinuousSlider::setMoveByWheel(bool move) {
 			_byWheelFinished = std::make_unique<SingleTimer>();
 			_byWheelFinished->setTimeoutHandler([this] {
 				if (_changeFinishedCallback) {
-					_changeFinishedCallback(getCurrentValue(getms()));
+					_changeFinishedCallback(getCurrentValue());
 				}
 			});
 		} else {
@@ -59,14 +54,8 @@ void ContinuousSlider::setMoveByWheel(bool move) {
 	}
 }
 
-void ContinuousSlider::setValue(float64 value, bool animated) {
+void ContinuousSlider::setValue(float64 value) {
-	if (animated) {
+	_value = value;
-		a_value.start(value);
-		_a_value.start();
-	} else {
-		a_value = anim::value(value, value);
-		_a_value.stop();
-	}
 	update();
 }
 
@@ -75,17 +64,6 @@ void ContinuousSlider::setFadeOpacity(float64 opacity) {
 	update();
 }
 
-void ContinuousSlider::step_value(float64 ms, bool timer) {
-	float64 dt = ms / (2 * AudioVoiceMsgUpdateView);
-	if (dt >= 1) {
-		_a_value.stop();
-		a_value.finish();
-	} else {
-		a_value.update(qMin(dt, 1.), anim::linear);
-	}
-	if (timer) update();
-}
-
 void ContinuousSlider::mouseMoveEvent(QMouseEvent *e) {
 	if (_mouseDown) {
 		updateDownValueFromPos(e->pos());
@@ -115,8 +93,7 @@ void ContinuousSlider::mouseReleaseEvent(QMouseEvent *e) {
 		if (_changeFinishedCallback) {
 			_changeFinishedCallback(_downValue);
 		}
-		a_value = anim::value(_downValue, _downValue);
+		_value = _downValue;
-		_a_value.stop();
 		update();
 	}
 }
@@ -139,8 +116,8 @@ void ContinuousSlider::wheelEvent(QWheelEvent *e) {
 		deltaX *= -1;
 	}
 	auto delta = (qAbs(deltaX) > qAbs(deltaY)) ? deltaX : deltaY;
-	auto finalValue = snap(a_value.to() + delta * coef, 0., 1.);
+	auto finalValue = snap(_value + delta * coef, 0., 1.);
-	setValue(finalValue, false);
+	setValue(finalValue);
 	if (_changeProgressCallback) {
 		_changeProgressCallback(finalValue);
 	}
@@ -197,7 +174,7 @@ void FilledSlider::paintEvent(QPaintEvent *e) {
 	auto lineWidthRounded = qFloor(lineWidth);
 	auto lineWidthPartial = lineWidth - lineWidthRounded;
 	auto seekRect = getSeekRect();
-	auto value = getCurrentValue(ms);
+	auto value = getCurrentValue();
 	auto from = seekRect.x(), mid = qRound(from + value * seekRect.width()), end = from + seekRect.width();
 	if (mid > from) {
 		p.setOpacity(masterOpacity);
@@ -244,7 +221,7 @@ void MediaSlider::paintEvent(QPaintEvent *e) {
 	auto disabled = isDisabled();
 	auto over = getCurrentOverFactor(ms);
 	auto seekRect = getSeekRect();
-	auto value = getCurrentValue(ms);
+	auto value = getCurrentValue();
 
 	// invert colors and value for vertical
 	if (!horizontal) value = 1. - value;

Telegram/SourceFiles/ui/widgets/continuous_sliders.h

@@ -38,7 +38,7 @@ public:
 	}
 
 	float64 value() const;
-	void setValue(float64 value, bool animated);
+	void setValue(float64 value);
 	void setFadeOpacity(float64 opacity);
 	void setDisabled(bool disabled);
 	bool isDisabled() const {
@@ -69,9 +69,8 @@ protected:
 	float64 fadeOpacity() const {
 		return _fadeOpacity;
 	}
-	float64 getCurrentValue(TimeMs ms) {
+	float64 getCurrentValue() {
-		_a_value.step(ms);
+		return _mouseDown ? _downValue : _value;
-		return _mouseDown ? _downValue : a_value.current();
 	}
 	float64 getCurrentOverFactor(TimeMs ms) {
 		return _disabled ? 0. : _a_over.current(ms, _over ? 1. : 0.);
@@ -91,7 +90,6 @@ private:
 		return _byWheelFinished != nullptr;
 	}
 
-	void step_value(float64 ms, bool timer);
 	void setOver(bool over);
 	float64 computeValue(const QPoint &pos) const;
 	void updateDownValueFromPos(const QPoint &pos);
@@ -107,10 +105,7 @@ private:
 	bool _over = false;
 	Animation _a_over;
 
-	// This can animate for a very long time (like in music playing),
+	float64 _value = 0.;
-	// so it should be a BasicAnimation, not an Animation.
-	anim::value a_value;
-	BasicAnimation _a_value;
 
 	bool _mouseDown = false;
 	float64 _downValue = 0.;