add interface to access the cur size of readyElems;takeplace of tryToPreCreate by forceToPreCreate
add interface to access the cur size of readyElems;takeplace of tryToPreCreate by forceToPreCreate

wjingzhe/ParkourJingz,wjingzhe/A_ParkourJingz,wjingzhe/ParkourJingz,wjingzhe/A_ParkourJingz,wjingzhe/ParkourJingz,wjingzhe/ParkourJingz,wjingzhe/A_ParkourJingz,wjingzhe/ParkourJingz,wjingzhe/ParkourJingz,wjingzhe/A_ParkourJingz,wjingzhe/A_ParkourJingz,wjingzhe/A_ParkourJingz