PHP Code:
for (temp.weapon: player.weapons)
{
// Code
}
temp.weapon.name will get the weapon name, and I think either temp.weapon.icon or temp.weapon.image or so will get the image (someone correct me if I am wrong).
I guess to draw all icons onto one panel, you could use a GuiDrawingPanel. Similarly you could spawn other GUI controls such as GuiBitmapButtonCtrls for each weapon.