Gesture recognizer on a circular view

ios, swift, uitapgesturerecognizer

Solution

You can override this method in CircleView:

override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
    let center = CGPoint(x: bounds.size.width/2, y: bounds.size.height/2)
    return pow(center.x-point.x, 2) + pow(center.y - point.y, 2) <= pow(bounds.size.width/2, 2)
}

All touches not belonging to the circle will be ignored.

More details:

https://developer.apple.com/reference/uikit/uiview/1622469-hittest https://developer.apple.com/reference/uikit/uiview/1622533-point

The main point is that you don't need to call neither `hitTest` nor `pointInside` methods, you just override them in your custom view and system will call them whenever it needs to know if a touch should be handled by this view.

In your case you've got a `UITableViewCell` with a `CircleView` in it, right? You've added a gesture recognizer to `CircleView` and overriden `pointInside` method, so a touch will be handled by `CircleView` itself if a touch point is inside the circle, otherwise event will be passed further, handled by cell and therefore `didSelectRowAtIndexPath` will be called.

Problem

In each cell of my collection view is a circular UIView. This has been achieved by creating a custom subclass of `UIView`, which I have called `CircleView`, and setting `layer.cornerRadius = self.frame.size.width/2` in the subclass' `awakeFromNib()` I want to add a gesture recognizer to each CircleView. I have done this in the collection view's `cellForItemAtIndexPath`: ``` let gestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(tap(_:))) cell.circleView.addGestureRecognizer(gestureRecognizer) ``` The problem is that the gesture recognizer is called whenever a tap occurs anywhere within the bounds of the original square UIView. I want to only recognize taps that occur within the circle. I have tried to solve this issue in the following ways: In the CircleView's `awakeFromNib()` I set `self.clipsToBounds = true` (no effect) Also in the CircleView's `awakeFromNib()` I set `layer.masksToBounds = true` (no effect) Thank you in advance for your ideas and suggestions.

Original source