Python:QtGui.QProgressBar 颜色

Question

我想知道是否有办法自定义进度条的颜色(QtGui.QProgressBar)。假设我们希望在条形图达到 100% 时将其变为绿色。

这是一个工作示例:

import sys, time
from PyQt4 import QtCore, QtGui

class PbWidget(QtGui.QProgressBar):
    def __init__(self, parent=None, total=20):
        super(PbWidget, self).__init__()
        self.setMinimum(1)
        self.setMaximum(total)        
        self._active = False  

    def update_bar(self, to_add_number):
        while True:
            time.sleep(0.01)
            value = self.value() + to_add_number            
            self.setValue(value)
            QtGui.qApp.processEvents()
            if (not self._active or value >= self.maximum()):                
                break
        self._active = False

    def closeEvent(self, event):
        self._active = False


class MainWindow(QtGui.QMainWindow):
    def __init__(self):
        super(MainWindow, self).__init__()
        self.main_layout = QtGui.QVBoxLayout()

        self.pb=PbWidget(total=101)
        self.main_layout.addWidget(self.pb)

        ok_button = QtGui.QPushButton("Press to update Progress Bar")
        ok_button.clicked.connect(self.OK)      
        self.main_layout.addWidget(ok_button)       

        central_widget = QtGui.QWidget()
        central_widget.setLayout(self.main_layout)
        self.setCentralWidget(central_widget)

    def OK(self):
        self.pb.update_bar(10)

if __name__ == '__main__':
    import sys
    app = QtGui.QApplication(sys.argv)
    window = MainWindow()
    window.resize(480, 320)
    window.show()
    sys.exit(app.exec_())

Answer 1

是的，为此使用 CSS。是的 CSS 你读得很好! ;)

将此函数添加到您的 PbWidget 类:

def change_color(self, color):
    template_css = """QProgressBar::chunk { background: %s; }"""
    css = template_css % color
    self.setStyleSheet(css)

颜色参数需要类似:“黄色”、“蓝色”、“红色”……以及十六进制符号:“#FFD45”等……

您可以在 update_bar 中调用此函数，并根据进度条值向其传递一些颜色。例如:

def update_bar(self, to_add_number):
    while True:
        time.sleep(0.5)
        value = self.value() + to_add_number            
        self.setValue(value)
        if value > 50:
            self.change_color("yellow")
        QtGui.qApp.processEvents()
        if (value >= self.maximum()):                
            break
    self._active = False

要更改其他视觉属性，请访问:Qt StyleSheet Reference并寻找 QtProgressBar。祝你好运!!!