Your expression is not very clear. The most important thing about autolayout animation is to grasp the state of the view. Simply calling layoutIfNeeded will only render the last effect. The view state must be saved before reaching a state point. To put it simply, after the animation is executed, use layoutIfNeeded to achieve the effect. If there are other animations, you need to use setNeedsLayout. After that, implement the view attributes that need to be changed; finally call layoutIfNeeded again;

// 大概代码就是这样：
// 首先确定 视图的最终位置；也可以是上一次动画结束
[view layoutIfNeeded];
// 然后让视图进入下一次动画准备状态
[view setNeedsLayout];
// *** 这里实现一些变化代码
view.snp.top = ....
// 最后再执行这个。如果是动画，就在 UIView animate 中执行。
[view layoutIfNeeded];
// 这样就 OK 了。