QT白皮书学习资料

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QT的国际化
国际化的一般操作步骤：
1、编写源代码 2、在*.pro文件中添加TRANSLATIONS += ＊.ts ，有多少中语言 就添加多少个ts文件 3、运行lupdate *.pro 生成ts文件。lupdate会根据源代码中的内容 提取出待翻译的字段，然后生成ts文件 4、用qt linguist打开ts文件，并翻译相应字段 5、运行lrelease *.pro生成qm文件。lrelease会根据ts文件生成二进 制的qm翻译文件 6、在主函数中安装QTranslator对象，或在*.qrc文件中添加qm文件
QT如何调用外部程序
QProcess
QProcess* myProcess=new QProcess; myProcess->addArgument( "ls" ); myProcess->addArgument( "-a" ); myProcess->start();
QThread
MyThread *thread=new MyThread; thread->start(); (…run())
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QT程序设计常见问题和方法
QT的国际化 QT的组件化 QT如何调用外部程序 QT的调试接口
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QT的国际化
在文本显示上，Qt 使用了Unicode 作为内部编 码，可以同时支持多种编码。 为 Qt 增加一种 编码的支持也比较方便，只要增加该编码和 Unicode的转换编码便可以了 Qt Linguist — 被称为Qt语言家的Linguist是 用于界面国际化的重要工具， 但其实它并不能 帮你翻译，它的主要任务只是读取翻译文件、为 翻译人员提供友好的翻译界面。

如何学习Qt我们假设你已经熟悉C++了！请先阅读一下Qt白皮书。

它包含一个关于Qt软件的概述，并且提供了一些用来示范使用Qt进行编程的代码的片断。

它会给你一个“大的图画”。

如果你想要完全的在C++中进行编程，不使用任何设计工具的帮助下在代码中设计你的界面，请阅读教程。

教程1就是被设计成把你带入Qt编程的一个教程，它更强调的是编写代码而不是一个特征的漫游。

教程2是一个更加真实的例子，示范了如何编写菜单、工具条、文件的载入和保存、对话框等地那个。

如果你想使用一个设计工具来设计你的用户界面，那么你至少要先阅读Qt设计器手册的前几章。

在这之后，学习一下上面提到的纯粹的C++教程（教程1和教程2）还是很值得的。

到现在为止，如果你已经完成了一些小的可以工作的应用程序并且对Qt编程有了一个主要的了解。

你可以直接开始你自己的项目了，但我们建议你阅读一些关键的概述来加深你对Qt的理解：对象模型和信号和槽。

在这里我们建议你看一下概述并且阅读一些和你的项目相关的文章。

你也许会发现浏览和你项目做相同事情的实例的源代码是非常有用的。

你也可以阅读Qt的源代码，因为它们也被提供。

如果你运行demo这个应用程序（在$QTDIR/examples/demo），你就会看到很多运转中的Qt窗口部件Qt提供了广泛的文档，完全前后参考的超文本，所以你可以很容易地按你喜欢的方式进行点击。

在文档中，你最经常使用的部分可能就是API参考。

每一个链接都提供了一个不同的方式来导航API参考，全都试试，看哪一个更适合你。

你现在应该已经准备好你的伟大工程：祝你好运，玩得开心！Qt教程一——共十四步这个教程介绍了使用Qt工具包进行图形用户界面编程。

它没有包括所有的东西：强调的是教授一种图形用户界面编程的编程思想，并且介绍Qt的特征也是必需的。

一些通常情况下使用的特征在这个教程里没有用到。

第一章开始讲述一个十行的Hello World程序并且后来的每一章都介绍了一个或几个更多的概念。

附录I 英文资料翻译QT 4.0 Whitepapper1. IntroductionQt is the de facto standard C++ framework for high performance cross-platform Software development. In addition to an extensive C++ class library ,Qt includes tools to make writing applications fast and stra ightforward. Qt’s cross-platform capabilities and internationalization support ensure that Qt applications reach the widest possible market.The Qt C++ frame work has been at the heart of commercial applications since1995. Qt is used by companies and organizations as diverse as Adobe., Boeing., IBM., Motorola., NASA, Skype., and by numerous smaller companies and organizations. Qt 4 is designed to be easier to use than previous versions of Qt, while adding more powerful functionality. Qt’s classes are fully featured and provide consistent interfaces to assist learning, reduce developer workload, and increase programmer productivity. Qt is, and always has been, fully object-oriented.This whitepaper gives an overview of Qt’s tools and functionality. Each sec tion begins with a non-technical introduction before providing a more detailed description of relevant features . Links to online resources are also given for each subject area.1.1. Executive SummaryQt includes a rich set of widgets(“controls”in Windows terminology)that provide standard GUI functionality. Qt introduces an innovative alternative for inter-object communication ,called “signals and slots”,that replaces the old and unsafe callback technique used in many legacy frameworks. Qt also provides a conventional event model for handling mouse clicks ,key presses, and other user input .Qt’s cross-platform GUI applications can support all the user interface functionality required by modern applications, such as menus, context menus ,drag and drop , and dockable toolbars.Qt also includes Qt Designer (page 20), a tool for graphically designing user interfaces. Qt Designer supports Qt’s powerful layout features (page 39) in addition to absolute positioning. Qt Designer can be used purely for GUI design, or to create entire applications with its support for integration with popular integrated development environments(IDEs).Qt has excellent supportfor2D and3Dgraphics. Qt is the de facto standard GUI framework for platform-independent OpenGL.programming.Qt4’spainting system offers high quality rendering across all supported platforms.Qt makes it possible to create platform-independent database applications using standard databases. Qt includes native drivers for Oracle ,Microsoft SQL Server, Sybase .Adaptive Server, IBMDB2, PostgreSQL., MySQL., Borland Interbase, SQLite, and ODBC-compliant databases. Qt includes database-specific widgets, and any built-in or custom widget can be made data-aware.Qt programs have native look and feel on all supported platf orms using Qt’s styles and themes support. From a single source tree, recompilation is all that is required toproduceapplicationsforWindows.98 to XP ,MacOS X. , Linux , Solaris ,HP-UX., and many other versions of Unix with X11..Qt applications can also be compiled to run on Qt opia. Qt’s qmake build tool produces makefiles or .dsp files appropriate to the target platform.Since Qt’s architecture takes advantage of the underlying platform, many customers use Qt for single-platform development on Windows, Mac OS X, and Unix because they prefer Qt’s approach. Qt includes support for important platform-specific features, such as ActiveX on Windows , and Motif on Unix . See the section on Qt’s Architecture for more information.Qt uses Unicode .throughout and has consider able support for internationalization. Qt includes Qt Linguist and other tools to support translators. Applications can easily use and mix text in Arabic, Chinese, English, Hebrew, Japanese, Russian, and other languages supported by Unicode.Qt includes a variety of domain-specific classes. For example, Qt has an XML module that includes SAX and DOM classes for reading and manipulating data stored in XML-based formats. Objects can be stored in memory using Qt’s STL-compatible collection classes, and handled using styles of iterators used in Java. And the C++ Standard Template Library(STL).Local and remote file handling using standard protocols are provided by Qt’s input/output and networking classes.Qt applications can have their functionality extended by plugins and dynamic libraries . Plugins provide additional codecs ,data base drivers ,image formats, styles, and widgets. Plugins and libraries can be sold as products in their own right.Qt is a mature C++ framework that is widely used around the world. In addition to Qt’s many commercial uses, the Open Source edition of Qt is the foundation of KDE ,the Linux desktop environment .Qt makes application development a pleasure ,with its cross platform build system, visual form design, and elegant API.2. WidgetsQt provides a rich set of standard widgets that can be used to create graphical user interfaces for applications. Qt’s widgets are flexible and can easily be subclassed to suit specialized requirements.Widgets are visual elements that are combined to create user interfaces. Buttons, menus, scroll bars, message boxes, and application windows are all examples of widgets. Qt’s widgets are not arbitrarily divided between “controls”and “containers”; all widgets can be used both as controls and as containers. Custom widgets can easily be created by subclassing existing Qt widgets, or created from scratch if necessary.Standard widgets are provided by the QWidget class and its subclasses, and custom widgets can be created by subclassing them and reimplementing virtual functions.A widget may contain any number of child widgets. Child widgets are shown within the parent widget’s area. A widget with no parent is a top-level widget (a “window”), and usually has its own entry in the desktop environ ment’s task bar. Qt imposes no arbitrary limitations on widgets. Any widget can be a top-level widget; any widget can be a child of any other widget. The position of child widgets within the parent’s area can be set automatically using layout managers, or manually if preferred. When a parent widget is disabled , hidden , or deleted, the same action is recursively applied to all its child widgets.3. Signals and SlotsSignals and slots provide inter-object communication. They are easy to understand and use, and are fully supported by Qt Designer.GUI applications respond to user actions .For example, when a user clicks a menu item or a toolbar button, the application executes some code. More generally, we want objects of any kind to be able to communicate with each other. The programmer must relate events to the relevantcode. Older toolkits use mechanisms that are not type-safe(i.e. ,they are crash-prone), are inflexible ,and are not object-oriented.Trolltech has invented a solution called “signals and slots.” The signals and slots mechanism is a powerful inter-object communication mechanism that can be used to completely replace the crude callbacks and message maps used by legacy toolkits. Signals and slots are flexible ,fully object-oriented, and implemented in C++.To associate some code with a button using the old callback mechanism, it is necessary to pass a function pointer to the button. When the button is clicked, the function is then called. Old toolkits do not ensure that arguments of the correct type are given to the function when it is called, making crashes more likely .Another problem with the callback approach is that it tightly binds the GUI element to the functionality, making it difficult to develop classes independently.Qt’s signals and slots mechanism is different. Qt widgets emit signals when events occur.4. GUI ApplicationsBuilding modern GUI applications with Qt is fast and simple, and can be achieved by hand coding or by using Qt Designer ,Qt’s visual design tool.Qt provides all the classes and functions necessary to create modern GUI applications .Qt can be used to create both “main window”style applications with a menu bar ,toolbars ,and status bar surrounding a central area ,and “dialog”style applications that use buttons an d possibly tabs to present options and information. Qt supports both SDI(single document interface) and MDI(multiple document interface). Qt also supports drag and drop and the clipboard.5. Qt DesignerQt Designer is a graphical user interface design tool for Qt applications. Applications can be written entirely as source code ,or using Qt Designer to speed up development. A component-based architecture makes it possible for developers to extend Qt Designer with custom widgets and extensions, and even integrate it into integrated development environments.Designing a form with Qt Designer is a simple process. Developers drag widgets from a toolbox onto a form, and use standard editing tools to select, cut, paste, and resize them. Each widget’s properties can then be changed using the property editor. The precise positions and sizes of the widgets do not matter. Developers select widgets and apply layouts to them. For example, some button widgets could be selected and laid out side by side by choosing the “lay out horizontally” option. This approach makes design very fast, and the finished forms will scale properly to fit whatever window size the end-user prefers. See Layouts on page 39 for information about Qt’s automatic layouts.Qt Designer eliminates the time-consuming “compile ,link ,and run”cycle for user interface design. This makes it easy to correct or change designs. Qt Designer’s preview options let developers see their forms in other styles ;for example ,a Macintosh developer can preview a form in the Windows style.Commercial licensees on Windows can enjoy Qt Designer’s user interface design facilities from with in Microsoft Visual Studio ..On Mac OS X , developers can use Qt Designer from with in Apple’s Xcode environment.QT4.0 白皮书1. 简介Qt是一种标准的C++框架，进行高性能跨平台的软件开发。

QT基础学习知识整理1.重要内容：1)信号和槽机制2)事件处理机制3)布局管理器4)绘图5)网络6)多线程7)其他（定时器，中文显示）2.1 一个简单的例子不可免俗的,从最简单的基本窗口产生开始介绍，窗口标题就叫作First Qt！!好了，请新增一个目录hello，并在当中使用任一编辑器来编辑一个hello.cpp的档案，内容如下：hello。

cpp#include 〈QApplication>#include 〈QLabel〉int main（int argc，char *argv［]) ｛QApplication app（argc, argv）;QLabel *label = new QLabel(”Hello！World! Orz。

”）；label—〉setWindowTitle（”First Qt!”）;label—>resize（200, 50）；label—〉show（);return app。

exec()；｝要使用Qt的组件，必须含入（include）相对应的头文件,程序的第一行包含的QApplication与Qlabel头文件，稍后才可以使用QApplication与QLabel两个组件的定义类别.每个Qt窗口程序，都必须有且只能有一个QApplication对象,它管理了整个应用程序所需的资源，QLabel 是Qt的图型组件之一，继承自QWidget,Widget这个名称来自Window Gadget，表示可视的使用者接口组件，可接受使用者的动作操作，文字画面、按钮、滚动条、工具列甚至容器（Container）等都是一种Widget.C++程序从main开始,再来进行Qt组件的初始化动作，在第一行中：QApplication app（argc, argv）；QApplication负责程序的初始、结束及处理事件（event)的循环等，并提供基本的窗口外观，这个外观与系统的桌面环境有关，例如标题列的样式、窗口外观、系统功能键等，在不同的操作系统桌面环境下，会有各自不同的外观，QApplication 对象接受命令列自变量作为它的自变量，像是如果您没有设定窗口标题，且会使用执行文件的名称作为窗口标题名称，可以使用的自变量与其作用，可以查询Qt在线文件关于QApplication类别的说明。