Evas objects basic manipulation example
#ifdef HAVE_CONFIG_H
#include "config.h"
#else
#define PACKAGE_EXAMPLES_DIR "."
#endif
#include <Ecore.h>
#include <Ecore_Evas.h>
#include <stdio.h>
#include <errno.h>
#include "evas-common.h"
#define WIDTH (320)
#define HEIGHT (240)
static const char *img_path = PACKAGE_EXAMPLES_DIR EVAS_IMAGE_FOLDER "/enlightenment.png";
static const char *border_img_path = PACKAGE_EXAMPLES_DIR EVAS_IMAGE_FOLDER "/red.png";
struct test_data
{
Ecore_Evas *ee;
Evas *canvas;
Evas_Object *img, *bg, *clipper, *clipper_border, *text;
};
static struct test_data d = {0};
/* here just to keep our example's window size and background image's
* size in synchrony */
static void
_canvas_resize_cb(Ecore_Evas *ee)
{
int w, h;
ecore_evas_geometry_get(ee, NULL, NULL, &w, &h);
evas_object_resize(d.bg, w, h);
}
static void
_on_keydown(void *data EINA_UNUSED,
Evas *evas EINA_UNUSED,
Evas_Object *o EINA_UNUSED,
void *einfo)
{
Evas_Event_Key_Down *ev = einfo;
if (strcmp(ev->key, "h") == 0) /* print help */
{
fprintf(stdout, "commands are:\n"
"\to - change clipper's opacity\n"
"\tr - toggle clipper's color between red and white\n"
"\tc - toggle clipper's clipping function\n"
"\tv - toggle clipper's visibility\n");
return;
}
if (strcmp(ev->key, "o") == 0) /* change clipper's opacity */
{
int alpha, r, g, b;
evas_object_color_get(d.clipper, &r, &g, &b, &alpha);
evas_color_argb_unpremul(alpha, &r, &g, &b);
alpha -= 20;
if (alpha < 0)
alpha = 255;
evas_color_argb_premul(alpha, &r, &g, &b);
evas_object_color_set(d.clipper, r, g, b, alpha);
fprintf(stdout, "Changing clipper's opacity: %d%%\n",
(int)((alpha / 255.0) * 100));
return;
}
if (strcmp(ev->key, "r") == 0) /* toggle clipper's color
* between red and white */
{
int alpha, r, g, b;
fprintf(stdout, "Changing clipper's color to");
evas_object_color_get(d.clipper, &r, &g, &b, &alpha);
evas_color_argb_unpremul(alpha, &r, &g, &b);
if (g > 0)
{
fprintf(stdout, "red\n");
g = b = 0;
}
else
{
fprintf(stdout, "white\n");
g = b = 255;
}
evas_color_argb_premul(alpha, &r, &g, &b);
evas_object_color_set(d.clipper, r, g, b, alpha);
return;
}
if (strcmp(ev->key, "c") == 0) /* toggle clipper's clipping function */
{
fprintf(stdout, "Toggling clipping ");
if (evas_object_clip_get(d.img) == d.clipper)
{
evas_object_clip_unset(d.img);
fprintf(stdout, "off\n");
}
else
{
evas_object_clip_set(d.img, d.clipper);
fprintf(stdout, "on\n");
}
return;
}
if (strcmp(ev->key, "v") == 0) /* toggle clipper's visibility */
{
fprintf(stdout, "Clipper is now ");
if (evas_object_visible_get(d.clipper))
{
evas_object_hide(d.clipper);
fprintf(stdout, "hidden\n");
}
else
{
evas_object_show(d.clipper);
fprintf(stdout, "visible\n");
}
return;
}
}
int
main(void)
{
int err;
if (!ecore_evas_init())
return EXIT_FAILURE;
/* this will give you a window with an Evas canvas under the first
* engine available */
d.ee = ecore_evas_new(NULL, 10, 10, WIDTH, HEIGHT, NULL);
if (!d.ee)
goto error;
ecore_evas_callback_resize_set(d.ee, _canvas_resize_cb);
ecore_evas_show(d.ee);
/* the canvas pointer, de facto */
d.canvas = ecore_evas_get(d.ee);
d.bg = evas_object_rectangle_add(d.canvas);
evas_object_name_set(d.bg, "background rectangle");
evas_object_color_set(d.bg, 255, 255, 255, 255); /* white bg */
evas_object_move(d.bg, 0, 0); /* at canvas' origin */
evas_object_resize(d.bg, WIDTH, HEIGHT); /* covers full canvas */
evas_object_show(d.bg);
evas_object_focus_set(d.bg, EINA_TRUE);
evas_object_event_callback_add(
d.bg, EVAS_CALLBACK_KEY_DOWN, _on_keydown, NULL);
d.img = evas_object_image_filled_add(d.canvas);
evas_object_image_file_set(d.img, img_path, NULL);
err = evas_object_image_load_error_get(d.img);
if (err != EVAS_LOAD_ERROR_NONE)
{
goto panic;
}
else
{
evas_object_move(d.img, 0, 0);
evas_object_resize(d.img, WIDTH, HEIGHT);
evas_object_show(d.img);
fprintf(stdout, "Image object added, type is: %s\n",
evas_object_type_get(d.img));
}
/* border on the image's clipper, here just to emphasize its position */
d.clipper_border = evas_object_image_filled_add(d.canvas);
evas_object_image_file_set(d.clipper_border, border_img_path, NULL);
err = evas_object_image_load_error_get(d.clipper_border);
if (err != EVAS_LOAD_ERROR_NONE)
{
goto panic;
}
else
{
evas_object_image_border_set(d.clipper_border, 3, 3, 3, 3);
evas_object_image_border_center_fill_set(
d.clipper_border, EVAS_BORDER_FILL_NONE);
evas_object_move(d.clipper_border, (WIDTH / 4) - 3, (HEIGHT / 4) - 3);
evas_object_resize(
d.clipper_border, (WIDTH / 2) + 6, (HEIGHT / 2) + 6);
evas_object_show(d.clipper_border);
}
/* solid white clipper (note that it's the default color for a
* rectangle) - it won't change clippees' colors, then (multiplying
* by 255) */
d.clipper = evas_object_rectangle_add(d.canvas);
evas_object_move(d.clipper, WIDTH / 4, HEIGHT / 4);
evas_object_resize(d.clipper, WIDTH / 2, HEIGHT / 2);
evas_object_clip_set(d.img, d.clipper);
evas_object_show(d.clipper);
ecore_main_loop_begin();
ecore_evas_free(d.ee);
ecore_evas_shutdown();
return 0;
error:
fprintf(stderr, "you got to have at least one evas engine built and linked"
" up to ecore-evas for this example to run properly.\n");
panic:
ecore_evas_free(d.ee);
ecore_evas_shutdown();
return -1;
}