有手机输入键盘时切换横竖屏高度变化的问题

function resetIosScreen() {
	if ( window.orientation == 90 || window.orientation == -90 ) {

	        userHeight = window.screen.width;

	   } else {

	        userHeight = window.screen.height;

	    }

    $(".before").height(userHeight - 70);

    $(".prompt").height(userHeight);

}

if (/iPhone/.test(navigator.userAgent)) {

            resetIosScreen();

}

 $(window).on("orientationchange",function(){

                resetIosScreen();

});