Icon Button and Pixelmap

I am a beginner and there's one project going on where I'm supposed to change pixel map of an icon button every ten seconds. I have set up a timer and initially, I created as many buttons as the number of pixel maps to be changed. Then I showed one icon button and hid the rest. Nothing happened except that only the last icon button I added to the window is visible(cuz their locations are the same). 

I tried to find the function prototypes of the GUIX API in gx_api.h file and found the followings. But I am lost now.

gx_icon_button_create(GX_ICON_BUTTON *button, GX_CONST GX_CHAR *name, GX_WIDGET *parent, GX_RESOURCE_ID icon_id, ULONG style, USHORT icon_button_id, GX_CONST GX_RECTANGLE *size);

gx_icon_button_pixelmap_set(GX_ICON_BUTTON *button, GX_RESOURCE_ID icon_id);

I would appreciate if anyone point out my mistake and show me a snippet of codes. 

Thank you.