EFL Threading example 4

Now when you want to have a thread do some work, send back results to the mainloop and continue running but the mainloop controls when the thread should stop working, you need some extra flags.

This is an example of how you might use ecore_main_loop_thread_safe_call_async() and pthreads to do this.

EFL Threading example 5

EFL Threading example 6

//Compile with:
//gcc -o efl_thread_4 efl_thread_4.c -g `pkg-config --cflags --libs elementary`
#include <Elementary.h>
#include <pthread.h>
static Evas_Object *win = NULL;
static Evas_Object *rect = NULL;
struct info
{
double x, y;
};
static void my_thread_mainloop_code(void *data);
static pthread_t thread_id;
static pthread_mutex_t th_lock;
static int th_exit = 0;
// BEGIN - code running in my custom pthread instance
//
static void *
my_thread_run(void *arg EINA_UNUSED)
{
double t = 0.0;
// inside the pthread function lets loop forever incrementing a time point
for (;;)
{
struct info *inf = malloc(sizeof(struct info));
int do_exit;
if (inf)
{
inf->x = 200 + (200 * sin(t));
inf->y = 200 + (200 * cos(t));
// now call a function in the mainloop and pass it our allocated
// data that it will free when it gets it
ecore_main_loop_thread_safe_call_async
(my_thread_mainloop_code, inf);
}
// and sleep and loop
usleep(1000);
t += 0.02;
// in case someone has asked us to cancel - then cancel this loop
// co-operatively (cancelling is co-operative)
pthread_mutex_lock(&th_lock);
do_exit = th_exit;
pthread_mutex_unlock(&th_lock);
if (do_exit) break;
}
return NULL;
}
//
// END - code running in my custom pthread instance
static void
my_thread_new(void)
{
pthread_attr_t attr;
pthread_mutex_init(&th_lock, NULL);
if (pthread_attr_init(&attr) != 0)
perror("pthread_attr_init");
if (pthread_create(&thread_id, &attr, my_thread_run, NULL) != 0)
perror("pthread_create");
}
static void
my_thread_mainloop_code(void *data)
{
struct info *inf = data;
evas_object_move(rect, inf->x - 50, inf->y - 50);
free(inf);
}
// just test cancelling the thread
static void
down(void *data EINA_UNUSED, Evas *e EINA_UNUSED, Evas_Object *obj EINA_UNUSED, void *event_info EINA_UNUSED)
{
pthread_mutex_lock(&th_lock);
th_exit = 1;
pthread_mutex_unlock(&th_lock);
}
// on window delete - cancel thread then delete window and exit mainloop
static void
del(void *data EINA_UNUSED, Evas_Object *obj, void *event_info EINA_UNUSED)
{
pthread_mutex_lock(&th_lock);
th_exit = 1;
pthread_mutex_unlock(&th_lock);
evas_object_del(obj);
elm_exit();
}
EAPI_MAIN int
elm_main(int argc EINA_UNUSED, char **argv EINA_UNUSED)
{
Evas_Object *o;
elm_policy_set(ELM_POLICY_QUIT, ELM_POLICY_QUIT_LAST_WINDOW_CLOSED);
win = elm_win_util_standard_add("efl-thread-4", "EFL Thread 4");
evas_object_smart_callback_add(win, "delete,request", del, NULL);
o = evas_object_rectangle_add(evas_object_evas_get(win));
evas_object_color_set(o, 50, 80, 180, 255);
evas_object_resize(o, 100, 100);
evas_object_show(o);
// new in the examples - we have a mouse down on the blue box cancel
// the thread
evas_object_event_callback_add(o, EVAS_CALLBACK_MOUSE_DOWN, down, NULL);
rect = o;
// create custom thread to do some "work on the side"
my_thread_new();
evas_object_resize(win, 400, 400);
evas_object_show(win);
elm_run();
pthread_mutex_lock(&th_lock);
th_exit = 1;
pthread_mutex_unlock(&th_lock);
return 0;
}
ELM_MAIN()
EVAS_CALLBACK_MOUSE_DOWN
@ EVAS_CALLBACK_MOUSE_DOWN
Mouse Button Down Event.
Definition Evas_Common.h:422
ecore_main_loop_thread_safe_call_async
EAPI void ecore_main_loop_thread_safe_call_async(Ecore_Cb callback, void *data)
Calls callback asynchronously in the main loop.
Definition ecore.c:612
EINA_UNUSED
#define EINA_UNUSED
Used to indicate that a function parameter is purposely unused.
Definition eina_types.h:339
ELM_MAIN
#define ELM_MAIN()
macro to be used after the elm_main() function
Definition elm_general.h:556
elm_policy_set
Eina_Bool elm_policy_set(unsigned int policy, int value)
Set a new policy's value (for a given policy group/identifier).
Definition elm_main.c:1380
elm_exit
void elm_exit(void)
Ask to exit Elementary's main loop.
Definition elm_main.c:1373
elm_run
void elm_run(void)
Run Elementary's main loop.
Definition elm_main.c:1357
ELM_POLICY_QUIT_LAST_WINDOW_CLOSED
@ ELM_POLICY_QUIT_LAST_WINDOW_CLOSED
quit when the application's last window is closed
Definition elm_general.h:248
ELM_POLICY_QUIT
@ ELM_POLICY_QUIT
under which circumstances the application should quit automatically.
Definition elm_general.h:227
elm_win_util_standard_add
Evas_Object * elm_win_util_standard_add(const char *name, const char *title)
Adds a window object with standard setup.
Definition efl_ui_win.c:9587
Evas
Eo Evas
An opaque handle to an Evas canvas.
Definition Evas_Common.h:163
evas_object_show
EVAS_API void evas_object_show(Evas_Object *eo_obj)
Makes the given Evas object visible.
Definition evas_object_main.c:1814
evas_object_del
EVAS_API void evas_object_del(Evas_Object *obj)
Marks the given Evas object for deletion (when Evas will free its memory).
Definition evas_object_main.c:928
evas_object_color_set
EVAS_API void evas_object_color_set(Evas_Object *obj, int r, int g, int b, int a)
Sets the general/main color of the given Evas object to the given one.
Definition evas_object_main.c:2024
evas_object_event_callback_add
EVAS_API void evas_object_event_callback_add(Evas_Object *eo_obj, Evas_Callback_Type type, Evas_Object_Event_Cb func, const void *data)
Add (register) a callback function to a given Evas object event.
Definition evas_callbacks.c:478
evas_object_move
EVAS_API void evas_object_move(Evas_Object *obj, Evas_Coord x, Evas_Coord y)
Move the given Evas object to the given location inside its canvas' viewport.
Definition evas_object_main.c:1171
evas_object_evas_get
EVAS_API Evas * evas_object_evas_get(const Eo *eo_obj)
Get the Evas to which this object belongs to.
Definition evas_object_main.c:2662
Evas_Object
Efl_Canvas_Object Evas_Object
An Evas Object handle.
Definition Evas_Common.h:185
evas_object_resize
EVAS_API void evas_object_resize(Evas_Object *obj, Evas_Coord w, Evas_Coord h)
Changes the size of the given Evas object.
Definition evas_object_main.c:1236
evas_object_rectangle_add
EVAS_API Evas_Object * evas_object_rectangle_add(Evas *e)
Adds a rectangle to the given evas.
Definition evas_object_rectangle.c:78
evas_object_smart_callback_add
EVAS_API void evas_object_smart_callback_add(Evas_Object *eo_obj, const char *event, Evas_Smart_Cb func, const void *data)
Add (register) a callback function to the smart event specified by event on the smart object obj.
Definition evas_object_smart.c:1040