Different layouts in portrait and landscape mode

iPAD don't have the size class for Landscape mode. I think the reason is that it is not needed in most of the cases. However one can activate and deactivate constraints when device orientation change like the accepted answer.

The following can be helpful for iPhone user.

Yes this is possible in interface builder with autolayout and size classes. You will not need to code.

First you select size class wAny hAny

Here is how to select size class.

Add two views in your view controller. Red view on top and blue view below. Just like your first image.

Constraints on red view are:

• Top space to super view
• Leading space to super view
• Trailing space to super view
• height = 50

Constraints on blue view are:

• vertical space to red view
• leading space to super view
• trailing space to super view
• bottom space to super view

This is all set for Potrait mode.

Now you change size classes to wAny hCompact(The first two column in first row). this class is for iPhone landscape.

Now you have to use install and uninstall concept.

Constraints that will change for red view:

• Uninstall its height constriant for (wAny hCompact) size class as:

• Similary uninstall its Leading constraint. Add two new constraints to this red view in this class:
• Bottom space to superview
• Width constraint = 50

This will make red view to right side with 50 width.

Now constraint change for blue view:

• Uninstall Its vertical spacing, trailing space.

Add two new constraint:

• Vertical space to super view
• Trailing space to red View

This will attach red view left of blue view.

Hope it work for you.

You can achieve this through code First of all you have to make IBoutlet of your dynamic constraints

Constant Constraint: // these constraint will remain same in both orientations

1- RedView top Space to Superview

2- RedView Trailing Space to Superview

3- BlueView Leading Space to Superview

4- BlueView bottom Space to SuperView

Dynamic Constraint

Portrait Constraint:

1- RedView height

2- RedView Vertical Space to BlueView

3- RedView Leading Space to Superview

4- BlueView Trailing Space to Superview

LandScape Constraint:

1- RedView Width

2- RedView Horizontal Space to BlueView

3- RedView bottom Space to Superview

4- BlueView Top Space to Superview

Now You have to override method which is called on Orientation change

override func viewWillTransitionToSize(size: CGSize,   withTransitionCoordinator coordinator:    UIViewControllerTransitionCoordinator) {

    coordinator.animateAlongsideTransition({ (UIViewControllerTransitionCoordinatorContext) -> Void in

        let orient = UIApplication.sharedApplication().statusBarOrientation

        switch orient {
        case .Portrait:
            print("Portrait")
            self.ApplyportraitConstraint()
            break
            // Do something
        default:
            print("LandScape")
            // Do something else
            self.applyLandScapeConstraint()
            break
        }
        }, completion: { (UIViewControllerTransitionCoordinatorContext) -> Void in
            print("rotation completed")
    })
    super.viewWillTransitionToSize(size, withTransitionCoordinator: coordinator)
}

And call these 2 functions

Portrait Orientation Function

func ApplyportraitConstraint(){

 self.view.addConstraint(self.RedViewHeight)
 self.view.addConstraint(self.RedView_VerticalSpace_To_BlueView)
 self.view.addConstraint(self.RedView_LeadingSpace_To_SuperView)
 self.view.addConstraint(self.BlueView_TrailingSpace_To_SuperView)

 self.view.removeConstraint(self.RedViewWidth)
 self.view.removeConstraint(self.RedView_HorizontalSpace_To_BlueView)
 self.view.removeConstraint(self.RedView_BottomSpace_To_SuperView)          
 self.view.removeConstraint(self.BlueView_TopSpace_To_SuperView)


}

LandScape Orientation Function

    func applyLandScapeConstraint(){

    self.view.removeConstraint(self.RedViewHeight)
    self.view.removeConstraint(self.RedView_VerticalSpace_To_BlueView)
    self.view.removeConstraint(self.RedView_LeadingSpace_To_SuperView)
   self.view.removeConstraint(self.BlueView_TrailingSpace_To_SuperView)

    self.view.addConstraint(self.RedViewWidth)
    self.view.addConstraint(self.RedView_HorizontalSpace_To_BlueView)
    self.view.addConstraint(self.RedView_BottomSpace_To_SuperView)
    self.view.addConstraint(self.BlueView_TopSpace_To_SuperView)

}

Portrait ScreenShot: LandScape ScreenShot:

Hope it will Help to Understand it through Layout Managment through coding. If you still not able to Understand then Please Check my Code on

Github:

If you have warnings just set height and width's constraint priority to 999.