callbacks function of apply in glade

[<eg_hyy stu ust hk>]

Dear all,
I am a newbie and I have some question about the callbacks function of "apply" signal in glade.
I have a propertybox which have 3 pages with one "apply" button automatically created by glade. I set something in the apply callbacks function, and I find that each time I press the apply button, the program go into the apply callbacks function serveral times!!
I afraid that this will slow down my program. Because my apply callbacks function is quite complicated and long...and i afraid that if each time user click "apply" for once, but the program go into the apply callbacks function serveral times, this will really slow down my program.

I would be very pleased that u have some suggestion for me.