如何从现有窗口创建新的PyQt4窗口？

Question

我一直在尝试使用python3和Qt4从现有窗口调用一个新窗口.

我使用Qt Designer(主应用程序和另一个)创建了两个窗口,我将Qt Designer生成的.ui文件转换为.py脚本 - 但我似乎无法从主应用程序创建新窗口.

我试过这样做:

############### MAIN APPLICATION SCRIPT ################

from PyQt4 import QtCore, QtGui
import v2

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    _fromUtf8 = lambda s: s

class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(194, 101)
        self.button1 = QtGui.QPushButton(Form)
        self.button1.setGeometry(QtCore.QRect(50, 30, 99, 23))
        self.button1.setObjectName(_fromUtf8("button1"))

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

    def retranslateUi(self, Form):
        Form.setWindowTitle(QtGui.QApplication.translate("Form", "Form", None, QtGui.QApplication.UnicodeUTF8))
        self.button1.setText(QtGui.QApplication.translate("Form", "Ventana", None, QtGui.QApplication.UnicodeUTF8))

        self.button1.connect(self.button1, QtCore.SIGNAL(_fromUtf8("clicked()")), self.mbutton1)

    def mbutton1(self):
        v2.main()



if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    Form = QtGui.QWidget()
    ui = Ui_Form()
    ui.setupUi(Form)
    Form.show()
    sys.exit(app.exec_())

################## SECOND WINDOW #######################

from PyQt4 import QtCore, QtGui

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    _fromUtf8 = lambda s: s

class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(400, 300)
        self.label = QtGui.QLabel(Form)
        self.label.setGeometry(QtCore.QRect(160, 40, 57, 14))
        self.label.setObjectName(_fromUtf8("label"))

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

    def retranslateUi(self, Form):
        Form.setWindowTitle(QtGui.QApplication.translate("Form", "Form", None, QtGui.QApplication.UnicodeUTF8))
        self.label.setText(QtGui.QApplication.translate("Form", "LABEL 2", None, QtGui.QApplication.UnicodeUTF8))

def main():
    import sys
    app = QtGui.QApplication(sys.argv)
    Form = QtGui.QWidget()
    ui = Ui_Form()
    ui.setupUi(Form)
    Form.show()
    sys.exit(app.exec_())

但我收到此错误消息:

 QCoreApplication::exec: The event loop is already running
 QPixmap: Must construct a QApplication before a QPaintDevice

Answer 1

虽然pyuic可以使用该-x, --execute选项创建可执行脚本,但它主要用于测试.

的主要目的pyuic是创建静态从Qt的Desgner Python模块ui文件,让您导入包含的GUI类到应用程序中.

比方说,你已经创建了两个ui使用Qt Designer文件和将它们命名为v1.ui和v2.ui.

然后,您将创建两个python模块,如下所示:

pyuic4 -o v1.py v1.ui
pyuic4 -o v2.py v2.ui

接下来,您将编写一个单独的main.py脚本,从模块中导入GUI类,并根据需要创建它们的实例.

所以你main.py看起来像这样:

from PyQt4 import QtGui
from v1 import Ui_Form1
from v2 import Ui_Form2

class Form1(QtGui.QWidget, Ui_Form1):
    def __init__(self, parent=None):
        QtGui.QWidget.__init__(self, parent)
        self.setupUi(self)
        self.button1.clicked.connect(self.handleButton)
        self.window2 = None

    def handleButton(self):
        if self.window2 is None:
            self.window2 = Form2(self)
        self.window2.show()

class Form2(QtGui.QWidget, Ui_Form2):
    def __init__(self, parent=None):
        QtGui.QWidget.__init__(self, parent)
        self.setupUi(self)

if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = Form1()
    window.show()
    sys.exit(app.exec_())

请注意,我稍微更改了GUI类的名称以避免命名空间冲突.要为GUI类提供更好的名称,只需objectName在Qt Desgner中设置顶级类的属性即可.pyuic在你做出改变后不要忘记重新运行!

Answer 2

你只能创建一个QApplication.创建后,您可以创建所需的窗口数.

例如:

from PyQt4 import QtGui, QtCore

class MyWindow(QtGui.QDialog):    # any super class is okay
    def __init__(self, parent=None):
        super(MyWindow, self).__init__(parent)
        self.button = QtGui.QPushButton('Press')
        layout = QtGui.QHBoxLayout()
        layout.addWidget(self.button)
        self.setLayout(layout)
        self.button.clicked.connect(self.create_child)
    def create_child(self):
        # here put the code that creates the new window and shows it.
        child = MyWindow(self)
        child.show()


if __name__ == '__main__':
    # QApplication created only here.
    app = QtGui.QApplication([])
    window = MyWindow()
    window.show()
    app.exec_()

每次单击该按钮都会创建一个新窗口.

您可以调整上面的示例以使用您使用Designer创建的窗口.

在旁注:

永远不要编辑pyuic的结果.不应更改这些文件.这意味着:不要将mbutton1方法添加到Ui_Form.

如果你有mywindow_ui.pypyuic创建的文件,那么你创建文件mywindow.py并放置如下:

from PyQt4 import QtCore, QtGui
from mywindow_ui import Ui_MyWindow

class MyWindow(QtGui.QWidget, Ui_MyWindow):   #or whatever Q*class it is
    def __init__(self, parent=None):
        super(MyWindow, self).__init__(parent)
        self.setupUi(self)
    def create_child(self):   #here should go your mbutton1
        # stuff
#etc.

现在,从您的主文件中main.py:

from PyQt4 import QtGui

from mywindow import MyWindow


# ...

if __name__ == '__main__':
    app = QtGui.QApplication([])
    window = MyWindow()
    window.show()
    app.exec_()