Re: g_idle_add() clarification

[richard boaz <ivor boaz gmail com>]

hi,

Scanning() is being called as part of g_idle_add().  Scanning() returns FALSE, which = NULL in C, so your call to g_idle_add() at execution time resolves to:

g_idle_add((GSourceFunc) 0, (gpointer) 0);

this clearly won't work.

rewrite as:

Scanning_lvl = g_idle_add((GSourceFunc) Scanning, (gpointer) 0);

and make sure Scanning() is declared somewhere beforehand.

and then see if you don't get a different execution result.

r-

On Tue, Jan 20, 2015 at 4:47 PM, Ian Chapman <ichapman videotron ca> wrote:

Thanks for your reply Richard.
Yes, I know that.  I thought Scanning() was a lower level than the gtk window and thus the StartScan_active() would exit before the mainloop would add Scanning() and then only execute Scanning() when nothing else (signals) was active.

I was also asking about the GLib-CRITICAL stuff on exiting Scanning().  Ian.

On 01/20/2015 03:34 PM, richard boaz wrote:

hi,

you are calling the function Scanning() in the g_idle_add() call.

richard

On Tue, Jan 20, 2015 at 3:23 PM, Ian Chapman <ichapman videotron ca> wrote:

Hi all,

Sorry to bother but I'm lost with the workings of

guint g_idle_add ()

My code is as
follows

extern "C"

void on_StartScan_activate() //from gtk menu item

{ printf("Start Scan Activated. \n");

scan_on_fg =1;

Scanning_lvl = g_idle_add((GSourceFunc) Scanning(), (gpointer) 0);

printf("Exiting StartScan.\n");  //main.cpp, Line 129

return; }

I get to Scanning() okay but I don't exit on_StartScan_activeat() until I exit Scanning() (not what I expected).

Worse still when I step through Scanning as I exit I get

(gdb) next

(main:24011): GLib-CRITICAL **: g_idle_add_full: assertion `function != NULL' failed

on_StartScan_activate () at main.cpp:129

(gdb) next

Exiting StartScan.

guint Scanning(void)

{

while(1 == scan_on_fg)

{ //Bean counting with rest of GUI in control, I hoped. }

return(FALSE); //Remove this thread.

}

Regards Ian.

_______________________________________________
gtk-list mailing list
gtk-list gnome org
https://mail.gnome.org/mailman/listinfo/gtk-list