Python GUI --- PyQt

    Python GUI工具集包括Tkinter、wxPython、PyGTK、PyQt、PySide五种；由于早年学习过Qt，PyQt GUI界面可以通过Qt Designer设计，故选择PyQt；PyQt是Python编程语言和Qt库的成功融合。PyQt向Python程序员提供了使用完整Qt应用程序接口的方法。您几乎可以用Python做任何C++能做的事。既然是应用程序接口，用C++或是Python都是一样的。对我来说作为一种编程语言，python相对于c++的优点是在编程效率上。您可以看到标准的Qt例子移植到PyQt后的代码。它们具有相同的功能，使用相同的应用程序接口，但Python版的代码只有原来的50-60%，而且它们更容易阅读。

PyQt开发工具下载地址，安装包中自带Qt Designer

https://riverbankcomputing.com/software/pyqt/download

点击打开链接

python扩展名
1. *.py
    py就是最基本的源码扩展名。windows下直接双击运行会调用python.exe执行;
2. *.pyw
    pyw是另一种源码扩展名，跟py唯一的区别是在windows下双击pyw扩展名的源码会调用pythonw.exe执行源码，这种执行方式不 

    会有命令行窗口；主要用于GUI程序发布时不需要看到控制台信息的情况；
3. *.pyc
    在执行python代码时经常会看到同目录下自动生成同名的pyc文件。这是python源码编译后的字节码，一般会在代码执行时自动

    生成你代码中引用的py文件的pyc文件。这个文件可以直接执行，用文本编辑器打开也看不到源码；
4. *.pyo
    pyo是跟pyc类似的优化编码后的文件。

开发纯图形界面程序的时候，推荐暂时把 .pyw 改成 .py，以便运行时能调出控制台窗口，看到所有错误信息，方便除虫Debug。

1. 第一个PyQt程序---hello kitty

    __author__ = '[email protected]'

    import sys
    from PyQt4 import QtGui

    app = QtGui.QApplication(sys.argv)
    btn = QtGui.QPushButton("Hello Kitty!")
    btn.show()
    sys.exit(app.exec_()) 

保存为firt_pyqt.py,直接双击或者命令行下运行

2. 将Qt Designer的UI文件转化为py文件

    用编辑器打开UI文件，其实是xml类型文件

	
	
	 Dialog
	 
	  
	   
		0
		0
		400
		300
	   
	  
	  
	   Dialog
	  
	  
	   
		
		 130
		 130
		 75
		 23
		
	   
	   
		hello world
	   
	  
	 
	 
	 
	

命令行下转换：

C:\Python27\Lib\site-packages\PyQt4\uic\pyuic.py -o c:\first_qt.py c:\first_pyqt.ui

得到first_qt.py

	# -*- coding: utf-8 -*-

	# Form implementation generated from reading ui file 'c:\first_pyqt.ui'
	#
	# Created by: PyQt4 UI code generator 4.11.4
	#
	# WARNING! All changes made in this file will be lost!

	from PyQt4 import QtCore, QtGui

	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_Dialog(object):
		def setupUi(self, Dialog):
			Dialog.setObjectName(_fromUtf8("Dialog"))
			Dialog.resize(400, 300)
			self.pushButton = QtGui.QPushButton(Dialog)
			self.pushButton.setGeometry(QtCore.QRect(130, 130, 75, 23))
			self.pushButton.setObjectName(_fromUtf8("pushButton"))

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

		def retranslateUi(self, Dialog):
			Dialog.setWindowTitle(_translate("Dialog", "Dialog", None))
			self.pushButton.setText(_translate("Dialog", "hello world", None))

添加头文件和main函数

import sys
from PyQt4 import QtCore, QtGui

if __name__ == '__main__':
	app = QtGui.QApplication(sys.argv)
	mainWindow = QtGui.QDialog()
	myWindow = Ui_Dialog()
	myWindow.setupUi(mainWindow)
	mainWindow.show()
	sys.exit(app.exec_())

修改后的文件second_pyqt.py

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'c:\first_pyqt.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!
import sys
from PyQt4 import QtCore, QtGui

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_Dialog(object):
	def setupUi(self, Dialog):
		Dialog.setObjectName(_fromUtf8("Dialog"))
		Dialog.resize(400, 300)
		self.pushButton = QtGui.QPushButton(Dialog)
		self.pushButton.setGeometry(QtCore.QRect(130, 130, 75, 23))
		self.pushButton.setObjectName(_fromUtf8("pushButton"))

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

	def retranslateUi(self, Dialog):
		Dialog.setWindowTitle(_translate("Dialog", "Dialog", None))
		self.pushButton.setText(_translate("Dialog", "hello world", None))

if __name__ == '__main__':
		app = QtGui.QApplication(sys.argv)
		mainWindow = QtGui.QDialog()
		myWindow = Ui_Dialog()
		myWindow.setupUi(mainWindow)
		mainWindow.show()
		sys.exit(app.exec_())

3. 动态加载UI文件，实现代码与界面分离

__author__ = '[email protected]'

import sys
from PyQt4 import QtCore, QtGui, uic

if __name__ == '__main__':
	app = QtGui.QApplication(sys.argv)
	mWindow = uic.loadUi('first_pyqt.ui')
	mWindow.show()
	sys.exit(app.exec_())

保存为third_pyqt.py

4. PyQt中使用信号与槽

__author__ = '[email protected]'

import sys
from PyQt4 import QtCore, QtGui

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)  
    btn = QtGui.QPushButton("Hello Kitty!")  
    btn.show()  
    app.connect(btn, QtCore.SIGNAL("clicked()"), app, QtCore.SLOT("quit()"))
    app.exec_()  

保存为four_pyqt.py