I created a split view controller that displays two views, for example: 
When I compile it, it gives me this result: 
Unfortunately, the first view is not visible, and I have to drag it on the left side of the window to see two views:

First, why does this separation look like this? Why is it not in the right size from the start?
If I add this line to the viewDidLoad () function of my SplitViewController:
splitView.adjustSubviews()
Then two views with the same size appear, but I don’t understand what the adjustSubviews () function does, and I can’t control the position.
How to fix it programmatically? How to adjust the size of each view? Is there any way to configure it in the interface builder?
Thanks.
EDIT: now for this question there is a generosity of 50 points
source share