/* Simple XCB application drawing a box in a window */ #include <xcb/xcb.h> #include <stdio.h> #include <stdlib.h> int main() { xcb_connection_t *c; xcb_screen_t *s; xcb_window_t w; xcb_gcontext_t g; xcb_generic_event_t *e; uint32_t mask; uint32_t values[2]; int done = 0; xcb_rectangle_t r = { 20, 20, 60, 60 }; /* open connection with the server */ c = xcb_connect(NULL,NULL); if (xcb_connection_has_error(c)) { printf("Cannot open display\n"); exit(1); } /* get the first screen */ s = xcb_setup_roots_iterator( xcb_get_setup(c) ).data; /* create black graphics context */ g = xcb_generate_id(c); w = s->root; mask = XCB_GC_FOREGROUND | XCB_GC_GRAPHICS_EXPOSURES; values[0] = s->black_pixel; values[1] = 0; xcb_create_gc(c, g, w, mask, values); /* create window */ w = xcb_generate_id(c); mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK; values[0] = s->white_pixel; values[1] = XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_KEY_PRESS; xcb_create_window(c, s->root_depth, w, s->root, 10, 10, 100, 100, 1, XCB_WINDOW_CLASS_INPUT_OUTPUT, s->root_visual, mask, values); /* map (show) the window */ xcb_map_window(c, w); xcb_flush(c); /* event loop */ while (!done && (e = xcb_wait_for_event(c))) { switch (e->response_type & ~0x80) { case XCB_EXPOSE: /* draw or redraw the window */ xcb_poly_fill_rectangle(c, w, g, 1, &r); xcb_flush(c); break; case XCB_KEY_PRESS: /* exit on key press */ done = 1; break; } free(e); } /* close connection to server */ xcb_disconnect(c); return 0; } 
