The MenuBuilder is a hidden class but does contain a method to show icons. You will need to use reflection to show the icons in the menu. Try adding this in showPopop(View, int):
java
PopupMenu popup = new PopupMenu(mContext, v);
try {
Method method = popup.getMenu().getClass().getDeclaredMethod("setOptionalIconsVisible", boolean.class);
method.setAccessible(true);
method.invoke(popup.getMenu(), true);
} catch (Exception e) {
e.printStackTrace();
}