PyQt5-Chinese-tutorial/介绍.md

# PyQt5 简介

本教程的目的是带领你入门PyQt5。教程内所有代码都在Linux上测试通过。[PyQt4 教程](http://zetcode.com/gui/pyqt4/)是PyQt4的教程，PyQt4是一个Python（同时支持2和3）版的Qt库。

## 关于 PyQt5

PyQt5 是Digia的一套Qt5与python绑定的应用框架，同时支持2.x和3.x。本教程使用的是3.x。Qt库由Riverbank Computing开发，是最强大的GUI库之一 ，官方网站：www.riverbankcomputing.co.uk/news。

PyQt5是由一系列Python模块组成。超过620个类，6000和函数和方法。能在诸如Unix、Windows和Mac OS等主流操作系统上运行。PyQt5有两种证书，GPL和商业证书。

PyQt5类分为很多模块，主要模块有：

- QtCore
- QtGui
- QtWidgets
- QtMultimedia
- QtBluetooth
- QtNetwork
- QtPositioning
- Enginio
- QtWebSockets
- QtWebKit
- QtWebKitWidgets
- QtXml
- QtSvg
- QtSql
- QtTest

QtCore模块包含了核心的非GUI的功能。主要和时间、文件与文件夹、各种数据、流、URLs、mime类文件、进程与线程一起使用。
QtGui模块包含了窗口系统、事件处理、2D图像、基本绘画、字体和文字类。
QtWidgets类包含了一系列创建桌面应用的UI元素。
QtMultimedia包含了处理多媒体的内容和调用摄像头API的类。
QtBluetooth模块包含了查找和连接蓝牙的类。
QtNetwork包含了网络编程的类，这些工具能让TCP/IP和UDP开发变得更加方便和可靠。
QtPositioning包含了定位的类，可以使用卫星、WiFi甚至文本。
Engine包含了通过客户端进入和管理Qt Cloud的类。
QtWebSockets包含了WebSocket协议的类。
QtWebKit包含了一个基WebKit2的web浏览器。
QtWebKitWidgets包含了基于QtWidgets的WebKit1的类。
QtXml包含了处理xml的类，提供了SAX和DOM API的工具。
QtSvg提供了显示SVG内容的类，Scalable Vector Graphics (SVG)是一种是一种基于可扩展标记语言（XML），用于描述二维矢量图形的图形格式（这句话来自于维基百科）。
QtSql提供了处理数据库的工具。
QtTest提供了测试PyQt5应用的工具。

## PyQt4和PyQt5的区别

**PyQt5不兼容PyQt4**。PyQt5有一些巨大的改进。但是，迁移并不是很难，两者的区别：

- 重新组合模块，一些模块已经被废弃(QtScript)，有些被分为两个子模块(QtGui, QtWebKit)。
- New modules have been introduced, including QtBluetooth, QtPositioning, or Enginio.
PyQt5 supports only the new-style signal and slots handlig. The calls to SIGNAL() or SLOT() are no longer supported.
PyQt5 does not support any parts of the Qt API that are marked as deprecated or obsolete in Qt v5.0.
Python

python logo Python is a general-purpose, dynamic, object-oriented programming language. The design purpose of the Python language emphasizes programmer productivity and code readability. Python was initially developed by Guido van Rossum. It was first released in 1991. Python was inspired by ABC, Haskell, Java, Lisp, Icon, and Perl programming languages. Python is a high-level, general purpose, multiplatform, interpreted language. Python is a minimalistic language. One of its most visible features is that it does not use semicolons nor brackets. It uses indentation instead. There are two main branches of Python currently: Python 2.x and Python 3.x. Python 3.x breaks backward compatibility with previous releases of Python. It was created to correct some design flaws of the language and make the language more clean. The most recent version of Python 2.x is 2.7.9, and of Python 3.x is 3.4.2. Python is maintained by a large group of volunteers worldwide. Python is open source software. Python is an ideal start for those who want to learn programming.

Python programming language supports several programming styles. It does not force a programmer to a specific paradigm. Python supports object-oriented and procedural programming. There is also a limited support for functional programming.

The official web site for the Python programming language is python.org

Perl，Python，和Ruby是使用最广泛的脚本语言，它们有很多共同的特点，也是相互的竞争对手。