在PyQt中运行时自动更改Pixmap图片

Question

我希望使用一个有定义的延迟和使用存储在字符串列表中的图像位置的while循环自动更改窗口中显示的像素图像。 我尝试的所有可能性都导致第一张图像被显示，但在运行时没有改变。 只有在程序完成所有执行后才反映任何更改。

from PyQt4 import QtCore, QtGui
import time
import sys

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)


class Ui_Form(QtGui.QWidget):
    def __init__(self):
        QtGui.QWidget.__init__(self)
        self.setupUi(self)
    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(598, 555)
        self.horizontalLayout = QtGui.QHBoxLayout(Form)
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.start_pulse = QtGui.QPushButton(Form)
        self.start_pulse.setObjectName(_fromUtf8("start_pulse"))
        self.horizontalLayout.addWidget(self.start_pulse)
        self.label = QtGui.QLabel(Form)
        self.label.setAutoFillBackground(True)
        self.label.setText(_fromUtf8(""))
        self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI.png")))
        self.label.setScaledContents(True)
        self.label.setObjectName(_fromUtf8("label"))
        self.horizontalLayout.addWidget(self.label)

        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)


    def retranslateUi(self, Form):
        Form.setWindowTitle(_translate("Form", "Form", None))
        self.start_pulse.setText(_translate("Form", "start", None))
        self.start_pulse.clicked.connect(self.soumyajit)
    def soumyajit(self):
        j=0
        while(1):
            print("change")
            if j==0:
                self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI2.png")))
            if j==1:
                self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI.png")))
            if j==2:
                self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI2.png")))
            if j==3:
                self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI.png")))
            j=j+1
            #delay
            time.sleep(.5)
if __name__=='__main__':
        app=QtGui.QApplication(sys.argv)
        ex = Ui_Form()
        ex.show()
        sys.exit(app.exec_())

- Joey Pinto

Answer 1

以下是我从你的代码中修改后的代码，它能够很好地运行：

在PyQt中运行时自动更改Pixmap图像的原始代码

由WonJong Kim ([e-mail])修改以解决问题

import sys
import time
import numpy
from PyQt4 import QtCore, QtGui
import PyQt4.Qwt5 as Qwt

numPoints=1000
xs=numpy.arange(numPoints)
ys=numpy.sin(3.14159*xs*10/numPoints) #this is our data

try:
    fromUtf8 = QtCore.QString.fromUtf8

except AttributeError:
    def _fromUtf8(s):
    return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)

except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_Form(QtGui.QWidget):
    def __init__(self):
        QtGui.QWidget.__init__(self)
        self.setupUi(self)
        self.index = 0

    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(500, 300)
        self.horizontalLayout = QtGui.QHBoxLayout(Form)
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.start_pulse = QtGui.QPushButton(Form)
        self.start_pulse.setObjectName(_fromUtf8("start_pulse"))
        self.stop_pulse = QtGui.QPushButton(Form)
        self.stop_pulse.setObjectName(_fromUtf8("stop_pulse"))
        self.horizontalLayout.addWidget(self.start_pulse)
        self.horizontalLayout.addWidget(self.stop_pulse)
        self.label = QtGui.QLabel(Form)
        self.label.setAutoFillBackground(True)
        self.label.setText(_fromUtf8(""))
        self.label.setPixmap(QtGui.QPixmap(_fromUtf8("GUI.png")))
        self.label.setScaledContents(True)
        self.label.setObjectName(_fromUtf8("label"))
        self.horizontalLayout.addWidget(self.label)

        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)

    def refreshUi(self):
        if self.index%10==0:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/10.jpg")))
        if self.index%10==1:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/1.jpg")))
        if self.index%10==2:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/2.jpg")))
        if self.index%10==3:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/3.jpg")))
        if self.index%10==4:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/4.jpg")))
        if self.index%10==5:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/5.jpg")))
        if self.index%10==6:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/6.jpg")))
        if self.index%10==7:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/7.jpg")))
        if self.index%10==8:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/8.jpg")))
        if self.index%10==9:
            self.label.setPixmap(QtGui.QPixmap(_fromUtf8("Images/9.jpg")))

    def retranslateUi(self, Form):
        Form.setWindowTitle(_translate("Form", "Form", None))
        self.start_pulse.setText(_translate("Form", "start", None))
        self.start_pulse.clicked.connect(self.start)
        self.stop_pulse.setText(_translate("Form", "stop", None))
        self.stop_pulse.clicked.connect(self.stop)

    def start(self):
        self.timer1.start(500.0) #set the interval (in ms)

    def stop(self):
        self.timer1.stop() #stop the timer

    def change_index(self):
        self.index += 1


if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    win_plot = Ui_Form()

    win_plot.index = 0
    win_plot.timer = QtCore.QTimer() #start a timer (to call replot events)
    win_plot.timer.start(100.0) #set the interval (in ms)
win_plot.connect(win_plot.timer, QtCore.SIGNAL('timeout()'), win_plot.refreshUi)

win_plot.timer1 = QtCore.QTimer() #start a timer (to call replot events)
win_plot.connect(win_plot.timer1, QtCore.SIGNAL('timeout()'),
    win_plot.change_index)

# show the main window
win_plot.show()
sys.exit(app.exec_())

- Wonjong Kim

Answer 2

你在GUI线程中运行循环，导致应用程序冻结。这是一种不好的方法。您应该使用QTimer代替。使用timeout()信号在特殊槽内完成所有图像更改。 QTimer是异步的，因此它不会冻结您的应用程序。

您还可以在循环内调用processEvents()，但这不是一个好的解决方案，使用定时器比带有睡眠的循环更好。

- Jablonski