SlidingStackedWidget.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Created on 2018年11月24日
author: Irony
site: https://pyqt5.com , https://github.com/892768447
email: 892768447@qq.com
file:
description: 参考 http://qt.shoutwiki.com/wiki/Extending_QStackedWidget_for_sliding_page_animations_in_Qt
"""
from PyQt5.QtCore import Qt, pyqtProperty, QEasingCurve, QPoint, \
    QPropertyAnimation, QParallelAnimationGroup, QTimer
from PyQt5.QtWidgets import QStackedWidget


__Author__ = """By: Irony
QQ: 892768447
Email: 892768447@qq.com"""
__Copyright__ = 'Copyright (c) 2018 Irony'
__Version__ = 1.0


class SlidingStackedWidget(QStackedWidget):

    LEFT2RIGHT, RIGHT2LEFT, TOP2BOTTOM, BOTTOM2TOP, AUTOMATIC = range(5)

    def __init__(self, *args, **kwargs):
        super(SlidingStackedWidget, self).__init__(*args, **kwargs)
        self._pnow = QPoint(0, 0)
        # 动画速度
        self._speed = 500
        # 当前索引
        self._now = 0
        # 自动模式的当前索引
        self._current = 0
        # 下一个索引
        self._next = 0
        # 是否激活
        self._active = 0
        # 动画方向(默认是横向)
        self._orientation = Qt.Horizontal
        # 动画曲线类型
        self._easing = QEasingCurve.Linear
        # 初始化动画
        self._initAnimation()

    def setSpeed(self, speed=500):
        """设置动画速度
        :param speed:       速度值,默认值为500
        :type speed:        int
        """
        self._speed = speed

    @pyqtProperty(int, fset=setSpeed)
    def speed(self):
        return self._speed

    def setOrientation(self, orientation=Qt.Horizontal):
        """设置动画的方向(横向和纵向)
        :param orientation:    方向(Qt.Horizontal或Qt.Vertical)
        :type orientation:     http://doc.qt.io/qt-5/qt.html#Orientation-enum
        """
        self._orientation = orientation

    @pyqtProperty(int, fset=setOrientation)
    def orientation(self):
        return self._orientation

    def setEasing(self, easing=QEasingCurve.OutBack):
        """设置动画的曲线类型
        :param easing:    默认为QEasingCurve.OutBack
        :type easing:     http://doc.qt.io/qt-5/qeasingcurve.html#Type-enum
        """
        self._easing = easing

    @pyqtProperty(int, fset=setEasing)
    def easing(self):
        return self._easing

    def slideInNext(self):
        """滑动到下一页"""
        now = self.currentIndex()
        if now < self.count() - 1:
            self.slideInIdx(now + 1)
            self._current = now + 1

    def slideInPrev(self):
        """滑动到上一页"""
        now = self.currentIndex()
        if now > 0:
            self.slideInIdx(now - 1)
            self._current = now - 1

    def slideInIdx(self, idx, direction=4):
        """滑动到指定序号
        :param idx:               序号
        :type idx:                int
        :param direction:         方向,默认是自动AUTOMATIC=4
        :type direction:          int
        """
        if idx > self.count() - 1:
            direction = self.TOP2BOTTOM if self._orientation == Qt.Vertical else self.RIGHT2LEFT
            idx = idx % self.count()
        elif idx < 0:
            direction = self.BOTTOM2TOP if self._orientation == Qt.Vertical else self.LEFT2RIGHT
            idx = (idx + self.count()) % self.count()
        self.slideInWgt(self.widget(idx), direction)

    def slideInWgt(self, widget, direction):
        """滑动到指定的widget
        :param widget:        QWidget, QLabel, etc...
        :type widget:         QWidget Base Class
        :param direction:     方向
        :type direction:      int
        """
        if self._active:
            return
        self._active = 1
        _now = self.currentIndex()
        _next = self.indexOf(widget)
        if _now == next:
            self._active = 0
            return

        w_now = self.widget(_now)
        w_next = self.widget(_next)

        # 自动判断方向
        if _now < _next:
            directionhint = self.TOP2BOTTOM if self._orientation == Qt.Vertical else self.RIGHT2LEFT
        else:
            directionhint = self.BOTTOM2TOP if self._orientation == Qt.Vertical else self.LEFT2RIGHT
        if direction == self.AUTOMATIC:
            direction = directionhint

        # 计算偏移量
        offsetX = self.frameRect().width()
        offsetY = self.frameRect().height()
        w_next.setGeometry(0, 0, offsetX, offsetY)

        if direction == self.BOTTOM2TOP:
            offsetX = 0
            offsetY = -offsetY
        elif direction == self.TOP2BOTTOM:
            offsetX = 0
        elif direction == self.RIGHT2LEFT:
            offsetX = -offsetX
            offsetY = 0
        elif direction == self.LEFT2RIGHT:
            offsetY = 0

        # 重新定位显示区域外部/旁边的下一个窗口小部件
        pnext = w_next.pos()
        pnow = w_now.pos()
        self._pnow = pnow

        # 移动到指定位置并显示
        w_next.move(pnext.x() - offsetX, pnext.y() - offsetY)
        w_next.show()
        w_next.raise_()

        self._animnow.setTargetObject(w_now)
        self._animnow.setDuration(self._speed)
        self._animnow.setEasingCurve(self._easing)
        self._animnow.setStartValue(QPoint(pnow.x(), pnow.y()))
        self._animnow.setEndValue(
            QPoint(offsetX + pnow.x(), offsetY + pnow.y()))

        self._animnext.setTargetObject(w_next)
        self._animnext.setDuration(self._speed)
        self._animnext.setEasingCurve(self._easing)
        self._animnext.setStartValue(
            QPoint(-offsetX + pnext.x(), offsetY + pnext.y()))
        self._animnext.setEndValue(QPoint(pnext.x(), pnext.y()))

        self._next = _next
        self._now = _now
        self._active = 1
        self._animgroup.start()

    def _initAnimation(self):
        """初始化当前页和下一页的动画变量"""
        # 当前页的动画
        self._animnow = QPropertyAnimation(
            self, propertyName=b'pos', duration=self._speed,
            easingCurve=self._easing)
        # 下一页的动画
        self._animnext = QPropertyAnimation(
            self, propertyName=b'pos', duration=self._speed,
            easingCurve=self._easing)
        # 并行动画组
        self._animgroup = QParallelAnimationGroup(
            self, finished=self.animationDoneSlot)
        self._animgroup.addAnimation(self._animnow)
        self._animgroup.addAnimation(self._animnext)

    def setCurrentIndex(self, index):
        # 覆盖该方法实现的动画切换
        # super(SlidingStackedWidget, self).setCurrentIndex(index)
        # 坚决不能调用上面的函数,否则动画失效
        self.slideInIdx(index)

    def setCurrentWidget(self, widget):
        # 覆盖该方法实现的动画切换
        super(SlidingStackedWidget, self).setCurrentWidget(widget)
        # 坚决不能调用上面的函数,否则动画失效
        self.setCurrentIndex(self.indexOf(widget))

    def animationDoneSlot(self):
        """动画结束处理函数"""
        # 由于重写了setCurrentIndex方法所以这里要用父类本身的方法
#         self.setCurrentIndex(self._next)
        QStackedWidget.setCurrentIndex(self, self._next)
        w = self.widget(self._now)
        w.hide()
        w.move(self._pnow)
        self._active = 0

    def autoStop(self):
        """停止自动播放"""
        if hasattr(self, '_autoTimer'):
            self._autoTimer.stop()

    def autoStart(self, msec=3000):
        """自动轮播
        :param time: 时间, 默认3000, 3秒
        """
        if not hasattr(self, '_autoTimer'):
            self._autoTimer = QTimer(self, timeout=self._autoStart)
        self._autoTimer.stop()
        self._autoTimer.start(msec)

    def _autoStart(self):
        if self._current == self.count():
            self._current = 0
        self._current += 1
        self.setCurrentIndex(self._current)