from qtpy.QtWidgets import QApplication, QAbstractScrollArea, QGraphicsOpacityEffect, QWidget, QVBoxLayout, QHBoxLayout from qtpy.QtCore import QEvent, Qt, QPropertyAnimation, QTimer, Signal, QPoint, Property, QAbstractAnimation from qtpy.QtGui import QMouseEvent, QPainter, QColor class ScrollBarGroove(QWidget): """ Scroll bar groove """ def __init__(self, orient: Qt.Orientation, parent): super().__init__(parent=parent) if orient == Qt.Vertical: self.setFixedWidth(12) self.setLayout(QVBoxLayout(self)) self.layout().addStretch(1) self.layout().setContentsMargins(0, 3, 0, 3) else: self.setFixedHeight(12) self.setLayout(QHBoxLayout(self)) self.layout().addStretch(1) self.layout().setContentsMargins(3, 0, 3, 0) self.opacityEffect = QGraphicsOpacityEffect(self) self.opacityAni = QPropertyAnimation(self.opacityEffect, b'opacity', self) self.setGraphicsEffect(self.opacityEffect) self.opacityEffect.setOpacity(0) def fadeIn(self): self.opacityAni.setEndValue(1) self.opacityAni.setDuration(150) self.opacityAni.start() def fadeOut(self): self.opacityAni.setEndValue(0) self.opacityAni.setDuration(150) self.opacityAni.start() def paintEvent(self, e): painter = QPainter(self) painter.setRenderHints(QPainter.Antialiasing) painter.setPen(Qt.NoPen) painter.setBrush(QColor(0, 0, 0, 30)) painter.drawRoundedRect(self.rect(), 6, 6) # ScrollBarHandle, ScrollBar and FlowLayout are modified from https://github.com/zhiyiYo/PyQt-Fluent-Widgets/blob/master/qfluentwidgets/components/widgets/scroll_bar.py class ScrollBarHandle(QWidget): """ Scroll bar handle """ def __init__(self, orient: Qt.Orientation, parent=None, fadeout: bool = False): super().__init__(parent) self.orient = orient if fadeout: self.effect = effect = QGraphicsOpacityEffect(self, opacity=1.0) self.setGraphicsEffect(effect) self.fadeAnimation = QPropertyAnimation( self, propertyName=b"opacity", targetObject=effect, duration=300, startValue=1.0, endValue=0., ) # self.fadeAnimation.setEasingCurve(QEasingCurve.Type.InQuint) self.fadeAnimation.finished.connect(self.hide) fixsize = 5 self.anime_timer = QTimer(self) self.anime_timer.setSingleShot(True) self.anime_timer.timeout.connect(self.start_fade_animation) else: fixsize = 3 if orient == Qt.Vertical: self.setFixedWidth(fixsize) else: self.setFixedHeight(fixsize) self.fadeout = fadeout def start_fade_animation(self): self.show() if self.fadeAnimation.state() == QAbstractAnimation.State.Running: self.fadeAnimation.stop() self.fadeAnimation.start() def prepareFadeout(self): self.anime_timer.stop() self.anime_timer.start(700) if self.isHidden(): self.show() if self.fadeAnimation.state() == QAbstractAnimation.State.Running: self.fadeAnimation.stop() if self.effect.opacity() != 1.: self.effect.setOpacity(1.) def stopFadeout(self): if self.fadeAnimation.state() == QAbstractAnimation.State.Running: self.fadeAnimation.stop() self.anime_timer.stop() self.show() if self.effect.opacity() != 1.: self.effect.setOpacity(1.) def paintEvent(self, e): painter = QPainter(self) painter.setRenderHints(QPainter.Antialiasing) painter.setPen(Qt.NoPen) r = self.width() / 2 if self.orient == Qt.Vertical else self.height() / 2 c = QColor(0, 0, 0, 90) painter.setBrush(c) painter.drawRoundedRect(self.rect(), r, r) class ScrollBar(QWidget): """ Fluent scroll bar """ rangeChanged = Signal(tuple) valueChanged = Signal(int) sliderPressed = Signal() sliderReleased = Signal() sliderMoved = Signal() def __init__(self, orient: Qt.Orientation, parent: QAbstractScrollArea, fadeout: bool = False): super().__init__(parent) self.groove = ScrollBarGroove(orient, self) self.handle = ScrollBarHandle(orient, self, fadeout) self.timer = QTimer(self) self.scroll_area = parent self.fadeout = fadeout self._orientation = orient self._singleStep = 1 self._pageStep = 50 self._padding = 0 self._minimum = 0 self._maximum = 0 self._value = 0 self._isPressed = False self.isEnter = False self._isExpanded = False self._pressedPos = QPoint() self._isForceHidden = False if orient == Qt.Vertical: self.partnerBar = parent.verticalScrollBar() QAbstractScrollArea.setVerticalScrollBarPolicy(parent, Qt.ScrollBarAlwaysOff) else: self.partnerBar = parent.horizontalScrollBar() QAbstractScrollArea.setHorizontalScrollBarPolicy(parent, Qt.ScrollBarAlwaysOff) self.__initWidget(parent) def __initWidget(self, parent): self.groove.opacityAni.valueChanged.connect(self._onOpacityAniValueChanged) self.partnerBar.rangeChanged.connect(self.setRange) self.partnerBar.valueChanged.connect(self._onValueChanged) self.valueChanged.connect(self.partnerBar.setValue) parent.installEventFilter(self) self.setRange(self.partnerBar.minimum(), self.partnerBar.maximum()) self.setVisible(self.maximum() > 0 and not self._isForceHidden) self._adjustPos(self.parent().size()) def _onPageUp(self): self.setValue(self.value() - self.pageStep()) def _onPageDown(self): self.setValue(self.value() + self.pageStep()) def _onValueChanged(self, value): self.val = value if self.fadeout and not self.isEnter: self.handle.prepareFadeout() def value(self): return self._value @Property(int, notify=valueChanged) def val(self): return self._value @val.setter def val(self, value: int): if value == self.value(): return value = max(self.minimum(), min(value, self.maximum())) self._value = value self.valueChanged.emit(value) # adjust the position of handle self._adjustHandlePos() def minimum(self): return self._minimum def maximum(self): return self._maximum def orientation(self): return self._orientation def pageStep(self): return self._pageStep def singleStep(self): return self._singleStep def isSliderDown(self): return self._isPressed def setValue(self, value: int): self.val = value def setMinimum(self, min: int): if min == self.minimum(): return self._minimum = min self.rangeChanged.emit((min, self.maximum())) def setMaximum(self, max: int): if max == self.maximum(): return self._maximum = max self.rangeChanged.emit((self.minimum(), max)) def setRange(self, min: int, max: int): if min > max or (min == self.minimum() and max == self.maximum()): return self.setMinimum(min) self.setMaximum(max) self._adjustHandleSize() self._adjustHandlePos() self.setVisible(max > 0 and not self._isForceHidden) self.rangeChanged.emit((min, max)) def setPageStep(self, step: int): if step >= 1: self._pageStep = step def setSingleStep(self, step: int): if step >= 1: self._singleStep = step def setSliderDown(self, isDown: bool): self._isPressed = True if isDown: self.sliderPressed.emit() else: self.sliderReleased.emit() def expand(self): """ expand scroll bar """ if self._isExpanded or not self.isEnter: return self._isExpanded = True self.groove.fadeIn() def collapse(self): """ collapse scroll bar """ if not self._isExpanded or self.isEnter: return self._isExpanded = False self.groove.fadeOut() def enterEvent(self, e): self.isEnter = True self.timer.stop() self.timer.singleShot(200, self.expand) if self.fadeout: self.handle.stopFadeout() def leaveEvent(self, e): self.isEnter = False self.timer.stop() self.timer.singleShot(200, self.collapse) if self.fadeout: self.handle.prepareFadeout() def eventFilter(self, obj, e: QEvent): if obj is not self.parent(): return super().eventFilter(obj, e) # adjust the position of slider if e.type() == QEvent.Resize: self._adjustPos(e.size()) return super().eventFilter(obj, e) def resizeEvent(self, e): self.groove.resize(self.size()) def mousePressEvent(self, e: QMouseEvent): super().mousePressEvent(e) self._isPressed = True self._pressedPos = e.pos() if self.childAt(e.pos()) is self.handle or not self._isSlideResion(e.pos()): return if self.orientation() == Qt.Vertical: if e.pos().y() > self.handle.geometry().bottom(): value = e.pos().y() - self.handle.height() - self._padding else: value = e.pos().y() - self._padding else: if e.pos().x() > self.handle.geometry().right(): value = e.pos().x() - self.handle.width() - self._padding else: value = e.pos().x() - self._padding self.setValue(int(value / max(self._slideLength(), 1) * self.maximum())) self.sliderPressed.emit() def mouseReleaseEvent(self, e): super().mouseReleaseEvent(e) self._isPressed = False self.sliderReleased.emit() def mouseMoveEvent(self, e: QMouseEvent): if self.orientation() == Qt.Vertical: dv = e.pos().y() - self._pressedPos.y() else: dv = e.pos().x() - self._pressedPos.x() # don't use `self.setValue()`, because it could be reimplemented dv = int(dv / max(self._slideLength(), 1) * (self.maximum() - self.minimum())) ScrollBar.setValue(self, self.value() + dv) self._pressedPos = e.pos() self.sliderMoved.emit() def _adjustPos(self, size): if self.orientation() == Qt.Vertical: self.resize(12, size.height() - 2) self.move(size.width() - 13, 1) else: self.resize(size.width() - 2, 12) self.move(1, size.height() - 13) def _adjustHandleSize(self): p = self.parent() if self.orientation() == Qt.Vertical: total = self.maximum() - self.minimum() + p.height() s = int(self._grooveLength() * p.height() / max(total, 1)) self.handle.setFixedHeight(max(30, s)) else: total = self.maximum() - self.minimum() + p.width() s = int(self._grooveLength() * p.width() / max(total, 1)) self.handle.setFixedWidth(max(30, s)) def _adjustHandlePos(self): total = max(self.maximum() - self.minimum(), 1) delta = int(self.value() / total * self._slideLength()) if self.orientation() == Qt.Vertical: x = self.width() - self.handle.width() - 3 self.handle.move(x, self._padding + delta) else: y = self.height() - self.handle.height() - 3 self.handle.move(self._padding + delta, y) def _grooveLength(self): if self.orientation() == Qt.Vertical: return self.height() - 2 * self._padding return self.width() - 2 * self._padding def _slideLength(self): if self.orientation() == Qt.Vertical: return self._grooveLength() - self.handle.height() return self._grooveLength() - self.handle.width() def _isSlideResion(self, pos: QPoint): if self.orientation() == Qt.Vertical: return self._padding <= pos.y() <= self.height() - self._padding return self._padding <= pos.x() <= self.width() - self._padding def _onOpacityAniValueChanged(self): if not self.fadeout: opacity = self.groove.opacityEffect.opacity() if self.orientation() == Qt.Vertical: self.handle.setFixedWidth(int(3 + opacity * 3)) else: self.handle.setFixedHeight(int(3 + opacity * 3)) self._adjustHandlePos() def setForceHidden(self, isHidden: bool): """ whether to force the scrollbar to be hidden """ self._isForceHidden = isHidden self.setVisible(self.maximum() > 0 and not isHidden) def wheelEvent(self, e): QApplication.sendEvent(self.parent().viewport(), e)