iOS：如何从另一个视图控制器类更改视图大小/来源？

Question

I have two views(Storyboard scenes) on screen but I want to change the size/origin of " View A " from " View B ". But my below code is not working, the view remains the same:

Code added to viewDidLoad from " View B "

ViewA *viewA = [[ViewA alloc]init];
 viewA.view.frame = CGRectMake(0,100,200,2000);

If someone could please help I would be thankful :)

Answer 1

I want to change the size/origin of "View A" from "View B"

What's the relationship between the views? If the two views are managed by different view controllers, then they shouldn't talk to each other directly. Generally, a view that might have something to communicate to the rest of the world calls a method on its delegate, which is typically the view controller that manages it. That view controller would then take appropriate action -- update the data model, send a message to another view controller, post a notification, etc. The only object that should mess directly with a given view graph is the view controller for that graph.

Answer 2

There might be not enough details to give a good answer however assuming those views are part of the same view controller you would likely want to connect an action from viewA to your controller which would change viewB's frame.

Assuming these views have separate controllers whose parent is the AppDelegate you will want to forward that message to the parent and handle it from there.

If the action supposed to influence multiple behaviors in many controllers then you may also want to consider NSNotificationCenter route.