在PySide中创建字幕效果

您可以创建一个自定义窗口小部件，但是要避免实现许多方法的任务，可以利用

QLabel

class MarqueeLabel(QLabel):    def __init__(self, parent=None):        QLabel.__init__(self, parent)        self.px = 0        self.py = 15        self._direction = Qt.LeftToRight        self.setWordWrap(True)        self.timer = QTimer(self)        self.timer.timeout.connect(self.update)        self.timer.start(40)        self._speed = 2        self.textLength = 0        self.fontPointSize = 0        self.setAlignment(Qt.AlignVCenter)        self.setFixedHeight(self.fontMetrics().height())    def setFont(self, font):        QLabel.setFont(self, font)        self.setFixedHeight(self.fontMetrics().height())    def updateCoordinates(self):        align = self.alignment()        if align == Qt.AlignTop: self.py = 10        elif align == Qt.AlignBottom: self.py = self.height() - 10        elif align == Qt.AlignVCenter: self.py = self.height() / 2        self.fontPointSize = self.font().pointSize() / 2        self.textLength = self.fontMetrics().width(self.text())    def setAlignment(self, alignment):        self.updateCoordinates()        QLabel.setAlignment(self, alignment)    def resizeEvent(self, event):        self.updateCoordinates()        QLabel.resizeEvent(self, event)    def paintEvent(self, event):        painter = QPainter(self)        if self._direction == Qt.RightToLeft: self.px -= self.speed() if self.px <= -self.textLength:     self.px = self.width()        else: self.px += self.speed() if self.px >= self.width():     self.px = -self.textLength        painter.drawText(self.px, self.py + self.fontPointSize, self.text())        painter.translate(self.px, 0)    def speed(self):        return self._speed    def setSpeed(self, speed):        self._speed = speed    def setDirection(self, direction):        self._direction = direction        if self._direction == Qt.RightToLeft: self.px = self.width() - self.textLength        else: self.px = 0        self.update()    def pause(self):        self.timer.stop()    def unpause(self):        self.timer.start()

在以下链接中可以找到以下示例。

class Example(QWidget):    def __init__(self, parent=None):        QWidget.__init__(self, parent)        self.setWindowTitle("Marquee Effect")        self.setLayout(QVBoxLayout())        self.marqueeLabel = MarqueeLabel(self)        flayout = QFormLayout()        self.layout().addLayout(flayout)        le = QLineEdit(self)        le.textChanged.connect(self.marqueeLabel.setText)        le.setText("""Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.""")        slider = QSlider(Qt.Horizontal, self)        slider.valueChanged.connect(self.marqueeLabel.setSpeed)        slider.setValue(10)        rtl = QRadioButton("Right to Left", self)        ltr = QRadioButton("Left to Rigth", self)        rtl.toggled.connect(lambda state: self.marqueeLabel.setDirection(Qt.RightToLeft if state else  Qt.LeftToRight))        ltr.setChecked(True)        directionWidget = QWidget(self)        directionWidget.setLayout(QHBoxLayout())        directionWidget.layout().setContentsMargins(0, 0, 0, 0)        directionWidget.layout().addWidget(rtl)        directionWidget.layout().addWidget(ltr)        fontBtn = QPushButton("Font...", self)        fontBtn.clicked.connect(self.changeFont)        colorBtn = QPushButton("Color...", self)        colorBtn.clicked.connect(self.changeColor)        pauseBtn = QPushButton("Pause", self)        pauseBtn.setCheckable(True)        pauseBtn.toggled.connect(lambda state: self.marqueeLabel.pause() if state else self.marqueeLabel.unpause())        pauseBtn.toggled.connect(lambda state: pauseBtn.setText("Resume") if state else pauseBtn.setText("Pause"))        flayout.addRow("Change Text", le)        flayout.addRow("Change Speed", slider)        flayout.addRow("Direction", directionWidget)        flayout.addRow("fontBtn", fontBtn)        flayout.addRow("colorBtn", colorBtn)        flayout.addRow("Animation", pauseBtn)        self.layout().addWidget(self.marqueeLabel)    def changeColor(self):        palette = self.marqueeLabel.palette()        color = QColorDialog.getColor(palette.brush(QPalette.WindowText).color(), self)        if color.isValid(): palette.setBrush(QPalette.WindowText, color) self.marqueeLabel.setPalette(palette)    def changeFont(self):        font, ok = QFontDialog.getFont(self.marqueeLabel.font(), self)        if ok: self.marqueeLabel.setFont(font)if __name__ == '__main__':    import sys    app = QApplication(sys.argv)    w = Example()    w.show()    sys.exit(app.exec_())

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