view test/checkkeys.c @ 816:428f688f2ad2

Date: Fri, 13 Feb 2004 17:03:16 +0100 From: Max Horn Subject: Modifier key fix The internal modifier state can get out of sync with reality. To trigger this, do for example this: 1) Launch an SDL app 2) Alt-click on the desktop (this will hide the SDL app). 3) Bring the SDL app back to the front 4) SDL will still think alt is pressed (and as such will treat left clicks like middle clicks). If you press and release alt, it'll be fine again. The attached patch cures this by rechecking the modifier state whenever we process an event.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 13 Feb 2004 17:57:16 +0000
parents 806fcbde0af3
children be9c9c8f6d53
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/* Simple program:  Loop, watching keystrokes
   Note that you need to call SDL_PollEvent() or SDL_WaitEvent() to 
   pump the event loop and catch keystrokes.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "SDL.h"

static void print_modifiers(void)
{
	int mod;
	printf(" modifiers:");
	mod = SDL_GetModState();
	if(!mod) {
		printf(" (none)");
		return;
	}
	if(mod & KMOD_LSHIFT)
		printf(" LSHIFT");
	if(mod & KMOD_RSHIFT)
		printf(" RSHIFT");
	if(mod & KMOD_LCTRL)
		printf(" LCTRL");
	if(mod & KMOD_RCTRL)
		printf(" RCTRL");
	if(mod & KMOD_LALT)
		printf(" LALT");
	if(mod & KMOD_RALT)
		printf(" RALT");
	if(mod & KMOD_LMETA)
		printf(" LMETA");
	if(mod & KMOD_RMETA)
		printf(" RMETA");
	if(mod & KMOD_NUM)
		printf(" NUM");
	if(mod & KMOD_CAPS)
		printf(" CAPS");
	if(mod & KMOD_MODE)
		printf(" MODE");
}

static void PrintKey(SDL_keysym *sym, int pressed)
{
	/* Print the keycode, name and state */
	if ( sym->sym ) {
		printf("Key %s:  %d-%s ", pressed ?  "pressed" : "released",
					sym->sym, SDL_GetKeyName(sym->sym));
	} else {
		printf("Unknown Key (scancode = %d) %s ", sym->scancode,
					pressed ?  "pressed" : "released");
	}

	/* Print the translated character, if one exists */
	if ( sym->unicode ) {
		/* Is it a control-character? */
		if ( sym->unicode < ' ' ) {
			printf(" (^%c)", sym->unicode+'@');
		} else {
#ifdef UNICODE
			printf(" (%c)", sym->unicode);
#else
			/* This is a Latin-1 program, so only show 8-bits */
			if ( !(sym->unicode & 0xFF00) )
				printf(" (%c)", sym->unicode);
#endif
		}
	}
	print_modifiers();
	printf("\n");
}

int main(int argc, char *argv[])
{
	SDL_Event event;
	int done;
	Uint32 videoflags;

	/* Initialize SDL */
	if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {
		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
		exit(1);
	}
	atexit(SDL_Quit);

	videoflags = SDL_SWSURFACE;
	while( argc > 1 ) {
		--argc;
		if ( argv[argc] && !strcmp(argv[argc], "-fullscreen") ) {
			videoflags |= SDL_FULLSCREEN;
		} else {
			fprintf(stderr, "Usage: %s [-fullscreen]\n", argv[0]);
			exit(1);
		}
	}

	/* Set 640x480 video mode */
	if ( SDL_SetVideoMode(640, 480, 0, videoflags) == NULL ) {
		fprintf(stderr, "Couldn't set 640x480 video mode: %s\n",
							SDL_GetError());
		exit(2);
	}

	/* Enable UNICODE translation for keyboard input */
	SDL_EnableUNICODE(1);

	/* Enable auto repeat for keyboard input */
	SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY,
	                    SDL_DEFAULT_REPEAT_INTERVAL);

	/* Watch keystrokes */
	done = 0;
	while ( !done ) {
		/* Check for events */
		SDL_WaitEvent(&event);
		switch (event.type) {
			case SDL_KEYDOWN:
				PrintKey(&event.key.keysym, 1);
				break;
			case SDL_KEYUP:
				PrintKey(&event.key.keysym, 0);
				break;
			case SDL_MOUSEBUTTONDOWN:
				/* Any button press quits the app... */
			case SDL_QUIT:
				done = 1;
				break;
			default:
				break;
		}
	}
	return(0);
}