kolibrios-fun/contrib/sdk/sources/SDL-1.2.2/docs/html/guideeventexamples.html

239 lines
4.4 KiB
HTML
Raw Normal View History

<HTML
><HEAD
><TITLE
>Event Examples</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.64
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="Examples"
HREF="guideexamples.html"><LINK
REL="PREVIOUS"
TITLE="Examples"
HREF="guideexamples.html"><LINK
REL="NEXT"
TITLE="Audio Examples"
HREF="guideaudioexamples.html"></HEAD
><BODY
CLASS="SECT1"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>SDL Library Documentation</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="guideexamples.html"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 4. Examples</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="guideaudioexamples.html"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="GUIDEEVENTEXAMPLES"
>Event Examples</A
></H1
><P
></P
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="AEN375"
>Filtering and Handling Events</A
></H2
><P
><PRE
CLASS="PROGRAMLISTING"
>#include &#60;stdio.h&#62;
#include &#60;stdlib.h&#62;
#include "SDL.h"
/* This function may run in a separate event thread */
int FilterEvents(const SDL_Event *event) {
static int boycott = 1;
/* This quit event signals the closing of the window */
if ( (event-&#62;type == SDL_QUIT) &#38;&#38; boycott ) {
printf("Quit event filtered out -- try again.\n");
boycott = 0;
return(0);
}
if ( event-&#62;type == SDL_MOUSEMOTION ) {
printf("Mouse moved to (%d,%d)\n",
event-&#62;motion.x, event-&#62;motion.y);
return(0); /* Drop it, we've handled it */
}
return(1);
}
int main(int argc, char *argv[])
{
SDL_Event event;
/* Initialize the SDL library (starts the event loop) */
if ( SDL_Init(SDL_INIT_VIDEO) &#60; 0 ) {
fprintf(stderr,
"Couldn't initialize SDL: %s\n", SDL_GetError());
exit(1);
}
/* Clean up on exit, exit on window close and interrupt */
atexit(SDL_Quit);
/* Ignore key events */
SDL_EventState(SDL_KEYDOWN, SDL_IGNORE);
SDL_EventState(SDL_KEYUP, SDL_IGNORE);
/* Filter quit and mouse motion events */
SDL_SetEventFilter(FilterEvents);
/* The mouse isn't much use unless we have a display for reference */
if ( SDL_SetVideoMode(640, 480, 8, 0) == NULL ) {
fprintf(stderr, "Couldn't set 640x480x8 video mode: %s\n",
SDL_GetError());
exit(1);
}
/* Loop waiting for ESC+Mouse_Button */
while ( SDL_WaitEvent(&#38;event) &#62;= 0 ) {
switch (event.type) {
case SDL_ACTIVEEVENT: {
if ( event.active.state &#38; SDL_APPACTIVE ) {
if ( event.active.gain ) {
printf("App activated\n");
} else {
printf("App iconified\n");
}
}
}
break;
case SDL_MOUSEBUTTONDOWN: {
Uint8 *keys;
keys = SDL_GetKeyState(NULL);
if ( keys[SDLK_ESCAPE] == SDL_PRESSED ) {
printf("Bye bye...\n");
exit(0);
}
printf("Mouse button pressed\n");
}
break;
case SDL_QUIT: {
printf("Quit requested, quitting.\n");
exit(0);
}
break;
}
}
/* This should never happen */
printf("SDL_WaitEvent error: %s\n", SDL_GetError());
exit(1);
}</PRE
></P
></DIV
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="guideexamples.html"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="guideaudioexamples.html"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Examples</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="guideexamples.html"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Audio Examples</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>