objective-c - 自动布局-屏幕底部的UIView动画(Autolayout - UIView animation from the bottom of the screen)

Question

I am using autolayout in my application.

(我在应用程序中使用自动布局。)

I have a UIPicker at the bottom of screen.

(屏幕底部有一个UIPicker。)

What I want to do is I want to open UIPicker from the bottom of screen on click of UIButton as shown in image below

(我想做的是我想单击UIButton时从屏幕底部打开UIPicker，如下图所示)

I want to know

(我想知道)

1. which kind of constraint I have to set initially

   (我最初必须设置哪种约束)

2. which kind of constraint I have to implement programmatically and how it will be implemented?

   (我必须以编程方式实现哪种约束以及如何实现？)

How to get back to its original position?

(如何回到原来的位置？)

  ask by iPhone translate from so

Answer 1

Initially pin top of pickerView to bottom of SuperView and then when you want it to show you can pin bottom of pickerView to bottom of superView .

(最初针顶pickerView至bottom的SuperView ，然后当你想让它显示你可以固定bottom的pickerView至底部superView 。)

OR

(要么)

You can do higher animation by pinning bottom of pickerView to bottom of superView and set height to 0 and when you want to show set height constant to whatEver height is recquired.

(您可以通过将pickerView的底部固定到superView的底部并将高度设置为0来进行更高的动画处理，并且当您想将设置的高度常数显示为需要什么高度时。)