It is now possible to try the program on your own machine. It should look like the one shown in Figure 1.1. First, you will need to
install Qt 4.3.2 (or a later Qt 4 release), a process that is explained in Appendix A. From now on, we will assume that you have a
correctly installed copy of Qt 4 and that Qt's bin directory is in your PATH environment variable. (On Windows, this is done
automatically by the Qt installation program.) You will also need the program's code in a file called hello.cpp in a directory
called hello. You can type in hello.cpp yourself or copy it from the examples that accompany this book, where it is
available as examples/chap01/hello/hello.cpp. (All the examples are available from the book's web site,
http://www.informit.com/title/0132354160.)
Figure 1.1. Hello on Linux
From a command prompt, change the directory to hello, and type
qmake -project
to create a platform-independent project file (hello.pro), and then type
qmake hello.pro
to create a platform-specific makefile from the project file. (The qmake tool is covered in more detail in Appendix B.) Type
make to build the program. Run it by typing hello on Windows, ./hello on Unix, and open hello.app on Mac OS X.
To terminate the program, click the close button in the window's title bar.
If you are using Windows and have installed the Qt Open Source Edition and the MinGW compiler, you will have a shortcut to an
MS-DOS Prompt window that has all the environment variables correctly set up for Qt. If you start this window, you can compile
Qt applications within it using qmake and make as described previously. The executables produced are put in the application's
debug or release folder (e.g., C:\examples\chap01\hello\release\hello.exe).
If you are using Microsoft Visual C++ with a commercial version of Qt, you will need to run nmake instead of make.
Alternatively, you can create a Visual Studio project file from hello.pro by typing
qmake -tp vc hello.pro
and then build the program in Visual Studio. If you are using Xcode on Mac OS X, you can generate an Xcode project using the
command
qmake -spec macx-xcode hello.pro
Before we go on to the next example, let's have some fun: Replace the line
QLabel *label = new QLabel("Hello Qt!");
with
QLabel *label = new QLabel("<h2><i>Hello</i> "
"<font color=red>Qt!</font></h2>");
and rebuild the application. When run, it should look like Figure 1.2. As the example illustrates, it's easy to brighten up a Qt
application's user interface using some simple HTML-style formatting.
Figure 1.2. A label with basic HTML formatting
16
剩余733页未读，继续阅读
