How do I switch UISegmentedControl programmatically?

The selectedSegmentIndex property identifies the selected segment of a UISegmentedControl. Set this property to the any valid segment index, or UISegmentedControlNoSegment (-1) to turn off the current selection.

// select the first segment
segmented.selectedSegmentIndex = 0;

// turn off the current selection
segmented.selectedSegmentIndex = UISegmentedControlNoSegment;

Alternatively, after you have changed the selectedSegmentIndex call 'sendActionsForControlEvents:' for example

segmentedControl.selectedSegmentIndex = 0

[segmentedControl sendActionsForControlEvents:UIControlEventValueChanged];

In Swift:

segmentedControl.selectedSegmentIndex = 1

Swift 2:

segmentedControl.sendActionsForControlEvents(UIControlEvents.ValueChanged)

Swift 3:

segmentedControl.sendActions(for: UIControlEvents.valueChanged)

@jmstone response, true, this action will not invoke the valueChanged event for this control.

One way to overcome this is to just call the function yourself:

segmentedControl.selectedSegmentIndex = 3;
[self valueChangedMethod:segmentedControl];

This will call:

- (void)valueChangedMethod:(UISegmentedControl *)segmentedControl
{
    //continue your code here...
}

EDIT: as Yogesh Nikam Patil made me notice, UIControlEvents has been renamed from UIControlEvents to UIControl.Event. I've updated my code accordingly.

@arcady bob answer was the one that did the trick for me.

I just post an updated version for SWIFT 5:

yourSegmentedControl.selectedSegmentIndex = 0
yourSegmentedControl.sendActions(for: UIControl.Event.valueChanged)

If you use just the first line, the segmented will react accordingly graphically, but your IBAction associated with the segmented control won't be called. In a few words: the second line is like tapping on the segmented control. This is what I needed and what I was missing.