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diff --git a/documentation/src/basics.dox b/documentation/src/basics.dox deleted file mode 100644 index fc177c4ef..000000000 --- a/documentation/src/basics.dox +++ /dev/null @@ -1,352 +0,0 @@ -/** - - \page basics 2 - FLTK Basics - -This chapter teaches you the basics of compiling programs -that use FLTK. - -\section basics_writing Writing Your First FLTK Program - -All programs must include the file <tt><FL/Fl.H></tt>. -In addition the program must include a header file for each -FLTK class it uses. Listing 1 shows a simple "Hello, -World!" program that uses FLTK to display the window. - -\par Listing 1 - "hello.cxx" -\code -#include <FL/Fl.H> -#include <FL/Fl_Window.H> -#include <FL/Fl_Box.H> - -int main(int argc, char **argv) { - Fl_Window *window = new Fl_Window(300,180); - Fl_Box *box = new Fl_Box(20,40,260,100,"Hello, World!"); - box->box(FL_UP_BOX); - box->labelsize(36); - box->labelfont(FL_BOLD+FL_ITALIC); - box->labeltype(FL_SHADOW_LABEL); - window->end(); - window->show(argc, argv); - return Fl::run(); -} -\endcode - -<!-- NEED 2in --> - -After including the required header files, the program then creates a -window. All following widgets will automatically be children of this window. - -\code -Fl_Window *window = new Fl_Window(300,180); -\endcode - -Then we create a box with the "Hello, World!" string in it. FLTK automatically -adds the new box to <tt>window</tt>, the current grouping widget. - -\code -Fl_Box *box = new Fl_Box(20,40,260,100,"Hello, World!"); -\endcode - -Next, we set the type of box and the size, font, and style of the label: - -\code -box->box(FL_UP_BOX); -box->labelsize(36); -box->labelfont(FL_BOLD+FL_ITALIC); -box->labeltype(FL_SHADOW_LABEL); -\endcode - -We tell FLTK that we will not add any more widgets to <tt>window</tt>. - -\code -window->end(); -\endcode - -Finally, we show the window and enter the FLTK event loop: - -\code -window->show(argc, argv); -return Fl::run(); -\endcode - -The resulting program will display the window in Figure 2-1. -You can quit the program by closing the window or pressing the -<KBD>ESC</KBD>ape key. - -\image html hello.C.gif "Figure 2-1: The Hello, World! Window" -\image latex hello.C.eps "The Hello, World! Window" width=8cm -\subsection basics_creating Creating the Widgets - -The widgets are created using the C++ <tt>new</tt> operator. For -most widgets the arguments to the constructor are: - -\code -Fl_Widget(x, y, width, height, label) -\endcode - -The <tt>x</tt> and <tt>y</tt> parameters determine where the -widget or window is placed on the screen. In FLTK the top left -corner of the window or screen is the origin (i.e. x = 0, y = -0) and the units are in pixels. - -The <tt>width</tt> and <tt>height</tt> parameters determine -the size of the widget or window in pixels. The maximum widget -size is typically governed by the underlying window system or -hardware. - -<tt>label</tt> is a pointer to a character string to label -the widget with or <tt>NULL</tt>. If not specified the label -defaults to <tt>NULL</tt>. The label string must be in static -storage such as a string constant because FLTK does not make a -copy of it - it just uses the pointer. - -\subsection basics_hierarchies Creating Widget hierarchies - -Widgets are commonly ordered into functional groups, which -in turn may be grouped again, creating a hierarchy of widgets. -FLTK makes it easy to fill groups by automatically adding all widgets -that are created between a <tt>myGroup->begin()</tt> and -<tt>myGroup->end()</tt>. In this example, <tt>myGroup</tt> -would be the <i>current</i> group. - -Newly created groups and their derived widgets implicitly call -<tt>begin()</tt> in the constructor, effectively adding all -subsequently created widgets to itself until <tt>end()</tt> -is called. - -Setting the current group to <tt>NULL</tt> will stop automatic -hierarchies. New widgets can now be added manually using -<tt>Fl_Group::add(...)</tt> and <tt>Fl_Group::insert(...)</tt>. - -\subsection basics_getset Get/Set Methods - -<tt>box->box(FL_UP_BOX)</tt> sets the type of box the -Fl_Box draws, changing it from the default of -<tt>FL_NO_BOX</tt>, which means that no box is drawn. In our -"Hello, World!" example we use <tt>FL_UP_BOX</tt>, -which means that a raised button border will be drawn around -the widget. You can learn more about boxtypes in -<A href="common.html#boxtypes">Chapter 3</A>. - -You could examine the boxtype in by doing -<tt>box->box()</tt>. FLTK uses method name overloading to make -short names for get/set methods. A "set" method is always of -the form "void name(type)", and a "get" method is always -of the form "type name() const". - -\subsection basics_redrawing Redrawing After Changing Attributes - -Almost all of the set/get pairs are very fast, short inline -functions and thus very efficient. However, <i>the "set" methods -do not call <tt>redraw()</tt></i> - you have to call it -yourself. This greatly reduces code size and execution time. The -only common exceptions are <tt>value()</tt> which calls -<tt>redraw()</tt> and <tt>label()</tt> which calls -<tt>redraw_label()</tt> if necessary. - -\subsection basics_labels Labels - -All widgets support labels. In the case of window widgets, -the label is used for the label in the title bar. Our example -program calls the <tt>labelfont()</tt>,<tt> labelsize</tt>, -and <tt>labeltype()</tt> methods. - -All widgets support labels. In the case of window widgets, -the label is used for the label in the title bar. Our example -program calls the -<A href=Fl_Widget.html#Fl_Widget.labelfont><tt>labelfont</tt></A>, -<A href=Fl_Widget.html#Fl_Widget.labelsize><tt> labelsize</tt></A>, -and -<A href=Fl_Widget.html#Fl_Widget.labeltype><tt>labeltype</tt></A> -methods. - -The <tt>labelfont</tt> method sets the typeface and style -that is used for the label, which for this example we are using -<tt>FL_BOLD</tt> and <tt>FL_ITALIC</tt>. You can also specify -typefaces directly. - -The <tt>labelsize</tt> method sets the height of the font in pixels. - -The <tt>labeltype</tt> -method sets the type of label. FLTK supports normal, embossed, -and shadowed labels internally, and more types can be added as -desired. - -A complete list of all label options can be found in -<A href="common.html#labels">Chapter 3</A>. - -\subsection basics_showing Showing the Window - -The <tt>show()</tt> method shows the widget or window. For windows -you can also provide the command-line arguments to allow users to -customize the appearance, size, and position of your windows. - -\subsection basics_eventloop The Main Event Loop - -All FLTK applications (and most GUI applications in general) -are based on a simple event processing model. User actions such -as mouse movement, button clicks, and keyboard activity generate -events that are sent to an application. The application may then -ignore the events or respond to the user, typically by redrawing -a button in the "down" position, adding the text to an input -field, and so forth. - -FLTK also supports idle, timer, and file pseudo-events that -cause a function to be called when they occur. Idle functions -are called when no user input is present and no timers or files -need to be handled - in short, when the application is not doing -anything. Idle callbacks are often used to update a 3D display -or do other background processing. - -Timer functions are called after a specific amount of time -has expired. They can be used to pop up a progress dialog after -a certain amount of time or do other things that need to happen -at more-or-less regular intervals. FLTK timers are not 100% -accurate, so they should not be used to measure time intervals, -for example. - -File functions are called when data is ready to read or -write, or when an error condition occurs on a file. They are -most often used to monitor network connections (sockets) for -data-driven displays. - -FLTK applications must periodically check (Fl::check()) -or wait (Fl::wait()) for events or use the Fl::run() -method to enter a standard event processing loop. Calling -Fl::run() is equivalent to the following code: - -\code -while (Fl::wait()); -\endcode - -Fl::run() does not return until all of the windows -under FLTK control are closed by the user or your program. - -\section basics_standard_compiler Compiling Programs with Standard Compilers - -Under UNIX (and under Microsoft Windows when using the GNU development -tools) you will probably need to tell the compiler where to find the -header files. This is usually done using the <tt>-I</tt> option: - -\code -CC -I/usr/local/include ... -gcc -I/usr/local/include ... -\endcode - -The <tt>fltk-config</tt> script included with FLTK can be -used to get the options that are required by your compiler: - -\code -CC `fltk-config --cxxflags` ... -\endcode - -Similarly, when linking your application you will need to tell the -compiler to use the FLTK library: - -\code -CC ... -L/usr/local/lib -lfltk -lXext -lX11 -lm -gcc ... -L/usr/local/lib -lfltk -lXext -lX11 -lm -\endcode - -Aside from the "fltk" library, there is also a "fltk_forms" -library for the XForms compatibility classes, "fltk_gl" for the -OpenGL and GLUT classes, and "fltk_images" for the image file -classes, Fl_Help_Dialog widget, and system icon support. - -\note -The libraries are named "fltk.lib", "fltkgl.lib", "fltkforms.lib", -and "fltkimages.lib", respectively under Windows. - -As before, the <tt>fltk-config</tt> script included with FLTK can be -used to get the options that are required by your linker: - -\code -CC ... `fltk-config --ldflags` -\endcode - -<!-- NEED 2in --> - -The forms, GL, and images libraries are included with the "--use-foo" -options, as follows: - -\code -CC ... `fltk-config --use-forms --ldflags` -CC ... `fltk-config --use-gl --ldflags` -CC ... `fltk-config --use-images --ldflags` -CC ... `fltk-config --use-forms --use-gl --use-images --ldflags` -\endcode - -Finally, you can use the <tt>fltk-config</tt> script to -compile a single source file as a FLTK program: - -\code -fltk-config --compile filename.cpp -fltk-config --use-forms --compile filename.cpp -fltk-config --use-gl --compile filename.cpp -fltk-config --use-images --compile filename.cpp -fltk-config --use-forms --use-gl --use-images --compile filename.cpp -\endcode - -Any of these will create an executable named <tt>filename</tt>. - -\section basics_visual_cpp Compiling Programs with Microsoft Visual C++ - -In Visual C++ you will need to tell the compiler where to -find the FLTK header files. This can be done by selecting -"Settings" from the "Project" menu and then changing the -"Preprocessor" settings under the "C/C++" tab. You will also -need to add the FLTK and WinSock2 (WS2_32.LIB) libraries to -the "Link" settings. - -You can build your Microsoft Windows applications as Console or -WIN32 applications. If you want to use the standard C <tt>main()</tt> -function as the entry point, FLTK includes a <tt>WinMain()</tt> -function that will call your <tt>main()</tt> function for you. - -<I>Note: The Visual C++ 5.0 optimizer is known to cause problems with -many programs. We only recommend using the "Favor Small Code" -optimization setting.</I> The Visual C++ 6.0 optimizer seems to be much -better and can be used with the "optimized for speed" setting. - -\section basics_naming Naming - -All public symbols in FLTK start with the characters 'F' and 'L': - -\li Functions are either <tt>Fl::foo()</tt> or <tt>fl_foo()</tt>. - -\li Class and type names are capitalized: <tt>Fl_Foo</tt>. - -\li <A href="enumerations.html">Constants and enumerations</A> - are uppercase: <tt>FL_FOO</tt>. - -\li All header files start with <tt><FL/...></tt>. - -<!-- NEED 5in --> - -\section basics_headerfiles Header Files - -The proper way to include FLTK header files is: - -\code -#include <FL/Fl_xyz.H> -\endcode - -\note -Case <I>is</I> significant on many operating systems, -and the C standard uses the forward slash (/) to -separate directories. <i>Do not use any of the following -include lines:</i> - -\code -#include <FL\Fl_xyz.H> -#include <fl/fl_xyz.h> -#include <Fl/fl_xyz.h> -\endcode - -\htmlonly -<hr> -<a class="el" href="index.html">[Index]</a> -<a class="el" href="intro.html">[Previous] 1 - Introduction to FLTK</a> -<a class="el" href="common.html">[Next] 3 - Common Widgets and Attributes</a> -\endhtmlonly -*/ |