FillColor CheckBoxes and Signature

Hi, i need to know if theres an way to change the fillcolor from checkboxes and signature fields.

on Android there is global variant:public static int g_annot_transparency = 0x200040FF;

and other platforms has similar setting.

But it will change every field in the document, i need to change one or another after some event.

OK, seems your feature shall implement on canvas drawing.
i mean like on Windows, when you move cursor to a empty signature field, the field hilighted.

while on most mobile platform, no hover events, only has touch events.