使用QLabel在PyQt GUI中显示gif

Question

我按下按钮后试图显示加载gif。这是我目前的代码

import sys
from PyQt4 import QtGui, QtCore
from PyQt4.QtCore import *
from PyQt4.QtGui import *

class MainWindow (QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow,self).__init__(parent)
        self.setGeometry(50,50,240,320)
        self.home()
    def home(self):
        but = QtGui.QPushButton("Example", self)#Creates the brew coffee button
        but.clicked.connect(self.gif_display)
        but.resize(200,80)
        but.move(20,50)

        self.show()
    def gif_display(self):
        l = QMovieLabel('loading.gif')
        l.show()

class QMovieLabel(QLabel):
    def __init__(self, fileName):
        QLabel.__init__(self)
        m = QMovie(fileName)
        m.start()
        self.setMovie(m)

    def setMovie(self, movie):
        QLabel.setMovie(self, movie)
        s=movie.currentImage().size()
        self._movieWidth = s.width()
        self._movieHeight = s.height()

def run():
    app = QtGui.QApplication(sys.argv)
    GUI = MainWindow()
    sys.exit(app.exec_())
run()

我想在按下按钮后显示名为“loading.gif”的gif。按下按钮后没有任何内容出现，我不确定如何正确显示gif。 gif与我创建的屏幕尺寸相同（240x320）。

Answer 1

问题是QMovieLabel是gif_display中的局部变量，因此当函数完成运行时它将被删除，因此解决方案是避免删除它。有两个选项：使它成为类的属性或使其成为窗口的子项，我将显示第二个方法，因为我认为它是你想要的那个：

import sys
from PyQt4 import QtCore, QtGui

class MainWindow (QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow,self).__init__(parent)
        self.setGeometry(50,50,240,320)
        self.home()

    def home(self):
        but = QtGui.QPushButton("Example", self) # Creates the brew coffee button
        but.clicked.connect(self.gif_display)
        but.resize(200,80)
        but.move(20,50)
        self.show()

    @QtCore.pyqtSlot()
    def gif_display(self):
        l = QMovieLabel('loading.gif', self)
        l.adjustSize()
        l.show()

class QMovieLabel(QtGui.QLabel):
    def __init__(self, fileName, parent=None):
        super(QMovieLabel, self).__init__(parent)
        m = QtGui.QMovie(fileName)
        self.setMovie(m)
        m.start()

    def setMovie(self, movie):
        super(QMovieLabel, self).setMovie(movie)
        s=movie.currentImage().size()
        self._movieWidth = s.width()
        self._movieHeight = s.height()

def run():
    app = QtGui.QApplication(sys.argv)
    GUI = MainWindow()
    sys.exit(app.exec_())

if __name__ == '__main__':
    run()