PyQt5 --- 进度条拖动点击视频播放

最近学习pyqt5，做一个视频播放器，网上找了很多资料都没有关于python方面的视频进度条拖动点击的方法，几乎都是Qt的。对相关资料的查阅，发现开发过程其实差不多，为此做一下相关的总结。

一、UI的设计

UI设计就不多说了，可以使用Designer大概画一个。

ui.py

class Ui_MainWindow(QMainWindow):def __init__(self):super(Ui_MainWindow, self).__init__()self.ui_init()def ui_init(self):self.resize(320, 250)self.main_widget = QWidget()  # 创建窗口主部件self.main_widget.setObjectName("main_widget")self.main_layout = QGridLayout()  # 创建主部件的网格布局self.main_widget.setLayout(self.main_layout)  # 设置窗口主部件布局为网格布局self.centralwidget = QWidget()self.centralwidget.setObjectName("centralwidget")  # 设置核心部件self.main_layout.addWidget(self.centralwidget)self.setCentralWidget(self.main_widget)  # 设置中心窗口setCentralWidgetself.vbox = QVBoxLayout(self.centralwidget)self.setObjectName("vbox")self.topUi()self.playUi()self.barUi()self.bottomUi()self.retranslateUi()self.show()def topUi(self):self.top_btn = QPushButton()self.top_btn.setMaximumSize(QSize(200, 16777215))self.setObjectName("top_btn")self.top_label = QLabel()self.top_label.setMaximumSize(QSize(16777215, 10))self.top_label.setObjectName("top_label")self.top_hbox = QHBoxLayout()self.top_hbox.setObjectName("top_hbox")self.top_hbox.addWidget(self.top_btn)self.top_hbox.addWidget(self.top_label)self.vbox.addLayout(self.top_hbox)def playUi(self):self.groupBox = QGroupBox()self.groupBox.setObjectName("groupBox")self.gridLayout = QGridLayout(self.groupBox)self.setObjectName("gridLayout")# myVideoWidget重写QVideoWidget ，实现双击视频最大化self.widget = myVideoWidget()self.widget.setMaximumSize(QSize(16777215, 16777215))self.widget.setObjectName("widget")self.label = QLabel(self)self.label.setMaximumSize(QSize(16777215, 16777215))self.gridLayout.addWidget(self.label, 0, 0, 1, 1)self.vbox.addWidget(self.groupBox)def barUi(self):self.bar_hbox = QHBoxLayout()self.bar_hbox.setObjectName("bar_hbox")# CustomSlider 重写QSlider方法，实现拖动点击self.bar_slider = CustomSlider()self.bar_slider.setEnabled(False)   # 禁用self.bar_slider.setOrientation(Qt.Horizontal)self.bar_slider.setObjectName("bar_slider")self.bar_label = QLabel(self)self.bar_label.setMaximumSize(QSize(50, 10))self.bar_label.setObjectName("bar_label")self.bar_hbox.addWidget(self.bar_slider)self.bar_hbox.addWidget(self.bar_label)self.vbox.addLayout(self.bar_hbox)def bottomUi(self):self.bottom_hbox = QHBoxLayout()self.bottom_hbox.setObjectName("bottom_hbox")self.stop_btn = QPushButton()self.stop_btn.setObjectName("stop_btn")self.end_btn = QPushButton()self.end_btn.setObjectName("end_btn")spacerItem = QSpacerItem(40, 20, QSizePolicy.Expanding, QSizePolicy.Minimum)self.bottom_hbox.addItem(spacerItem)self.bottom_hbox.addWidget(self.stop_btn)self.bottom_hbox.addItem(spacerItem)self.bottom_hbox.addWidget(self.end_btn)self.bottom_hbox.addItem(spacerItem)self.vbox.addLayout(self.bottom_hbox)def retranslateUi(self):_translate = QCoreApplication.translate # QCoreApplication会构建出当前线程需要的事件驱动器self.setWindowTitle(_translate("main_widget", "播放器   开发者: hp"))self.top_btn.setText(_translate("main_widget", "打开文件"))self.top_label.setText(_translate("main_widget", ""))self.groupBox.setTitle(_translate("main_widget", "预览"))self.label.setText(_translate("main_widget", "Waiting for video..."))self.bar_label.setText(_translate("main_widget", "00:00:00"))self.stop_btn.setText(_translate("main_widget", "暂停"))self.end_btn.setText(_translate("main_widget", "结束"))

二、相关按钮的方法（继承UI）

相关方法我主要讲述播放视频与滑动块的点击滑动等相关方法，如有错误请及时指出，第一次在csdn写博客，若写的不足，请尽量包涵。

class MainFunction(Ui_MainWindow):def __init__(self):super(MainFunction, self).__init__()self.play_flag = False  # 播放暂停的标志self.videoFullScreen = False # 判断当前widget是否全屏self.timer = QTimer()      # 定义定时器self.maxValue = 1000       # 设置进度条的最大值self.trigger()             # 触发方法

触发方法的相关函数

    def trigger(self):# 定义playerself.player = QMediaPlayer()self.player.setVideoOutput(self.widget)self.top_btn.clicked.connect(self.openVideoFile)self.stop_btn.clicked.connect(self.playVideo)self.end_btn.clicked.connect(self.stopVideo)self.bar_slider.sliderMoved.connect(self.slider_progress_moved)self.bar_slider.sliderReleased.connect(self.slider_progress_released)self.bar_slider.customSliderClicked.connect(self.slider_progress_clicked)

播放视频使用的是QMediaPlayer

一开始采用positionChanged信号来驱动，但是发现，QSlider两个信号槽互相修改，容易出现冲突，导出程序异常，所以才去定时器QTimer修改Slider。

打开文件

def openVideoFile(self):self.player.setMedia(QMediaContent(QFileDialog.getOpenFileUrl()[0]))  # 选取视频文件self.gridLayout.addWidget(self.widget, 0, 0, 1, 1)self.bar_slider.setEnabled(True)self.bar_slider.setRange(0,self.maxValue)self.player.play()  # 播放视频self.FLAG_PLAY = Trueself.timer.setInterval(1000)self.timer.start()self.timer.timeout.connect(self.onTimerOut)

onTimerOut方法 调节进度条播放进度与显示播放时长

    def onTimerOut(self):self.bar_slider.setValue(round(self.player.position()*self.maxValue/self.player.duration()))m, s = divmod(self.player.position() / 1000, 60)h, m = divmod(m, 60)self.bar_label.setText("%02d:%02d:%02d" % (h, m, s))self.widget.doubleClickedItem.connect(self.videoDoubleClicked)

重写 QSlider 控制进度条拖动点击视频播放的操作

继承父类QSlider，重写mousePressEvent（按键释放）

class CustomSlider(QSlider):customSliderClicked = pyqtSignal(str)def __init__(self,parent=None):super(QSlider, self).__init__(parent)

继承父类的mousePressEvent方法，防止影响拖动操作

def mousePressEvent(self,QMouseEvent):super().mousePressEvent(QMouseEvent)    pos = QMouseEvent.pos().x() / self.width()self.setValue(round(pos*(self.maximum()-self.minimum())+self.minimum()))self.customSliderClicked.emit("mouse Press")

上面UI设计那已经替换了QSlider的方法为CustomSlider

对点击和拖动滑动块触发的方法

self.bar_slider.sliderMoved.connect(self.slider_progress_moved)
self.bar_slider.sliderReleased.connect(self.slider_progress_released)
self.bar_slider.customSliderClicked.connect(self.slider_progress_clicked)

sliderMoved（用户拖动滑块时触发）

    def slider_progress_moved(self):self.timer.stop()self.player.setPosition(round(self.bar_slider.value()*self.player.duration()/self.maxValue))

sliderReleased（用户释放滑块时触发）

    def slider_progress_released(self):self.timer.start()

customSliderClicked（自定方法，实现单击跳转至任意位置）

    def slider_progress_clicked(self):self.player.setPosition(round(self.bar_slider.value() * self.player.duration() / self.maxValue))