diff options
| author | Fabien Costantini <fabien@onepost.net> | 2008-10-14 22:12:25 +0000 |
|---|---|---|
| committer | Fabien Costantini <fabien@onepost.net> | 2008-10-14 22:12:25 +0000 |
| commit | 497afccb07164373e0de6639e754d7d691f1926f (patch) | |
| tree | 449d0b92ceb05f39617fe8fc2876d16eecde7460 /documentation/basics.html | |
| parent | e08fffdfe08bbc9320e39a15d162b6501abd4925 (diff) | |
Doxygen pdf man: First version added in documentation/fltk.pdf, old doc removed, images, dox files moved to a new src directory.
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@6431 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
Diffstat (limited to 'documentation/basics.html')
| -rw-r--r-- | documentation/basics.html | 367 |
1 files changed, 0 insertions, 367 deletions
diff --git a/documentation/basics.html b/documentation/basics.html deleted file mode 100644 index 42ce0131a..000000000 --- a/documentation/basics.html +++ /dev/null @@ -1,367 +0,0 @@ -<HTML> -<HEAD> - <TITLE>2 - FLTK Basics</TITLE> -</HEAD> -<BODY> - -<H1 ALIGN="RIGHT"><A NAME="basics">2 - FLTK Basics</A></H1> - -<P>This chapter teaches you the basics of compiling programs -that use FLTK.</P> - -<H2>Writing Your First FLTK Program</H2> - -<P>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.</P> - -<UL> -<P><I>Listing 1 - "hello.cxx"</I> -<PRE> -#include <FL/Fl.H> -#include <FL/Fl_Window.H> -#include <FL/Fl_Box.H> - -int main(int argc, char **argv) { - <A href="Fl_Window.html">Fl_Window</A> *window = new <A href="Fl_Window.html#Fl_Window.Fl_Window">Fl_Window</A>(300,180); - <A href="Fl_Box.html">Fl_Box</A> *box = new <A href="Fl_Box.html#Fl_Box.Fl_Box">Fl_Box</A>(20,40,260,100,"Hello, World!"); - box-><A href="Fl_Widget.html#Fl_Widget.box">box</A>(<A href="common.html#boxtypes">FL_UP_BOX</A>); - box-><A href="Fl_Widget.html#Fl_Widget.labelsize">labelsize</A>(36); - box-><A href="Fl_Widget.html#Fl_Widget.labelfont">labelfont</A>(<A href="drawing.html#fonts">FL_BOLD</A>+<A href="drawing.html#fonts">FL_ITALIC</A>); - box-><A href="Fl_Widget.html#Fl_Widget.labeltype">labeltype</A>(<A href="common.html#labels">FL_SHADOW_LABEL</A>); - window-><A href="Fl_Group.html#Fl_Group.end">end</A>(); - window-><A href="Fl_Window.html#Fl_Window.show">show</A>(argc, argv); - return <A href="Fl.html#Fl.run">Fl::run</A>(); -} -</PRE></UL> - -<!-- NEED 2in --> - -<P>After including the required header files, the program then creates a -window. All following widgets will automatically be children of this window.</P> - -<UL><PRE> -Fl_Window *window = new <A href="Fl_Window.html#Fl_Window">Fl_Window</A>(300,180); -</PRE></UL> - -<P>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.</P> - -<UL><PRE> -Fl_Box *box = new <A href="Fl_Box.html#Fl_Box">Fl_Box</A>(20,40,260,100,"Hello, World!"); -</PRE></UL> - -<P>Next, we set the type of box and the size, font, and style of the label:</P> - -<UL><PRE> -box-><A href="Fl_Widget.html#Fl_Widget.box">box</A>(FL_UP_BOX); -box-><A href=Fl_Widget.html#Fl_Widget.labelsize>labelsize</A>(36); -box-><A href=Fl_Widget.html#Fl_Widget.labelfont>labelfont</A>(FL_BOLD+FL_ITALIC); -box-><A href=Fl_Widget.html#Fl_Widget.labeltype>labeltype</A>(FL_SHADOW_LABEL); -</PRE></UL> - -<P>We tell FLTK that we will not add any more widgets to <tt>window</tt>.</P> - -<UL><PRE> -window-><A href=Fl_Group.html#Fl_Group.end>end</A>(); -</PRE></UL> - -<P>Finally, we show the window and enter the FLTK event loop:</P> - -<UL><PRE> -window-><A href=Fl_Window.html#Fl_Window.show>show</A>(argc, argv); -return <A href="Fl.html#Fl.run">Fl::run</A>(); -</PRE></UL> - -<P>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.</P> - -<P ALIGN="CENTER"><IMG src="hello.C.gif" alt="Hello, World! Window"><BR> -<I>Figure 2-1: The Hello, World! Window</I></P> - -<H3>Creating the Widgets</H3> - -<P>The widgets are created using the C++ <TT>new</TT> operator. For -most widgets the arguments to the constructor are:</P> - -<UL><PRE> -Fl_Widget(x, y, width, height, label) -</PRE></UL> - -<P>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.</P> - -<P>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.</P> - -<P><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.</P> - -<H3>Creating Widget hierarchies</H3> - -<P>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.</P> - -<P>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.</P> - -<P>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>.</P> - -<H3>Get/Set Methods</H3> - -<P><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>.</P> - -<P>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".</P> - -<H3>Redrawing After Changing Attributes</H3> - -<P>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.</P> - -<H3>Labels</H3> - -<P>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.</P> - -<P>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. </P> <P>The <TT>labelsize</TT> method sets -the height of the font in pixels. </P> <P>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.</P> - -<P>A complete list of all label options can be found in -<A href="common.html#labels">Chapter 3</A>.</P> - -<H3>Showing the Window</H3> - -<P>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.</P> - -<H3>The Main Event Loop</H3> - -<P>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.</P> - -<P>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.</P> - -<P>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.</P> - -<P>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.</P> - -<P>FLTK applications must periodically check -(<TT>Fl::check()</TT>) or wait (<TT>Fl::wait()</TT>) for events -or use the <A href="Fl.html#Fl.run"><TT>Fl::run()</TT></A> -method to enter a standard event processing loop. Calling -<TT>Fl::run()</TT> is equivalent to the following code:</P> - -<UL><PRE> -while (Fl::wait()); -</PRE></UL> - -<P><TT>Fl::run()</TT> does not return until all of the windows -under FLTK control are closed by the user or your program.</P> - -<H2>Compiling Programs with Standard Compilers</H2> - -<P>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:</P> - -<UL><PRE> -CC -I/usr/local/include ... -gcc -I/usr/local/include ... -</PRE></UL> - -<P>The <TT>fltk-config</TT> script included with FLTK can be -used to get the options that are required by your compiler:</P> - -<UL><PRE> -CC `fltk-config --cxxflags` ... -</PRE></UL> - -<P>Similarly, when linking your application you will need to tell the -compiler to use the FLTK library:</P> - -<UL><PRE> -CC ... -L/usr/local/lib -lfltk -lXext -lX11 -lm -gcc ... -L/usr/local/lib -lfltk -lXext -lX11 -lm -</PRE></UL> - -<P>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, <A -HREF="Fl_Help_Dialog.html#Fl_Help_Dialog"><CODE>Fl_Help_Dialog</CODE></A> -widget, and system icon support. - -<CENTER><TABLE WIDTH="80%" BORDER="1" CELLPADDING="10" BGCOLOR="#cccccc"> -<TR> - <TD><B>Note:</B> - <P>The libraries are named "fltk.lib", "fltkgl.lib", "fltkforms.lib", - and "fltkimages.lib", respectively under Windows. - </TD> -</TR> -</TABLE></CENTER> - -<P>As before, the <TT>fltk-config</TT> script included with FLTK can be -used to get the options that are required by your linker:</P> - -<UL><PRE> -CC ... `fltk-config --ldflags` -</PRE></UL> - -<!-- NEED 2in --> - -<P>The forms, GL, and images libraries are included with the "--use-foo" -options, as follows: - -<UL><PRE> -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` -</PRE></UL> - -<P>Finally, you can use the <TT>fltk-config</TT> script to -compile a single source file as a FLTK program: - -<UL><PRE> -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 -</PRE></UL> - -<P>Any of these will create an executable named <TT>filename</TT>. - -<H2>Compiling Programs with Microsoft Visual C++</H2> - -<P>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 -WinSock (WSOCK32.LIB) libraries to the "Link" -settings.</P> - -<P>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.</P> - -<P><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.</P> - -<H2>Naming</H2> - -<P>All public symbols in FLTK start with the characters 'F' and 'L':</P> - -<UL> - - <LI>Functions are either <TT>Fl::foo()</TT> or - <TT>fl_foo()</TT>.</LI> - - <LI>Class and type names are capitalized: - <TT>Fl_Foo</TT>.</LI> - - <LI><A href="enumerations.html">Constants and - enumerations</A> are uppercase: <TT>FL_FOO</TT>.</LI> - - <LI>All header files start with <TT><FL/...></TT>. - </LI> - -</UL> - -<!-- NEED 5in --> - -<H2>Header Files</H2> - -<P>The proper way to include FLTK header files is:</P> - -<UL><PRE> -#include <FL/Fl_xyz.H> -</PRE></UL> - -<CENTER><TABLE BORDER="1" CELLPADDING="10" BGCOLOR="#cccccc"> -<TR> - <TD><B>Note:</B> - - <P>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></P> - - <UL><PRE> - #include <FL\Fl_xyz.H> - #include <fl/fl_xyz.h> - #include <Fl/fl_xyz.h> - </PRE></UL> - - </TD> -</TR> -</TABLE></CENTER> - -</BODY> -</HTML> |