UIButton: Making the hit area larger than the default hit area

Solution 1:

Since I am using a background image, none of these solutions worked well for me. Here is a solution that does some fun objective-c magic and offers a drop in solution with minimal code.

First, add a category to UIButton that overrides the hit test and also adds a property for expanding the hit test frame.

UIButton+Extensions.h

@interface UIButton (Extensions)

@property(nonatomic, assign) UIEdgeInsets hitTestEdgeInsets;

@end

UIButton+Extensions.m

#import "UIButton+Extensions.h"
#import <objc/runtime.h>

@implementation UIButton (Extensions)

@dynamic hitTestEdgeInsets;

static const NSString *KEY_HIT_TEST_EDGE_INSETS = @"HitTestEdgeInsets";

-(void)setHitTestEdgeInsets:(UIEdgeInsets)hitTestEdgeInsets {
    NSValue *value = [NSValue value:&hitTestEdgeInsets withObjCType:@encode(UIEdgeInsets)];
    objc_setAssociatedObject(self, &KEY_HIT_TEST_EDGE_INSETS, value, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

-(UIEdgeInsets)hitTestEdgeInsets {
    NSValue *value = objc_getAssociatedObject(self, &KEY_HIT_TEST_EDGE_INSETS);
    if(value) {
        UIEdgeInsets edgeInsets; [value getValue:&edgeInsets]; return edgeInsets;
    }else {
        return UIEdgeInsetsZero;
    }
}

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
    if(UIEdgeInsetsEqualToEdgeInsets(self.hitTestEdgeInsets, UIEdgeInsetsZero) || !self.enabled || self.hidden) {
        return [super pointInside:point withEvent:event];
    }

    CGRect relativeFrame = self.bounds;
    CGRect hitFrame = UIEdgeInsetsInsetRect(relativeFrame, self.hitTestEdgeInsets);

    return CGRectContainsPoint(hitFrame, point);
}

@end

Once this class is added, all you need to do is set the edge insets of your button. Note that I chose to add the insets so if you want to make the hit area larger, you must use negative numbers.

[button setHitTestEdgeInsets:UIEdgeInsetsMake(-10, -10, -10, -10)];

Note: Remember to import the category (#import "UIButton+Extensions.h") in your classes.

Solution 2:

Just set the image edge inset values in interface builder.

Solution 3:

Here's an elegant solution using Extensions in Swift. It gives all UIButtons a hit area of at least 44x44 points, as per Apple's Human Interface Guidelines (https://developer.apple.com/ios/human-interface-guidelines/visual-design/layout/)

Swift 2:

private let minimumHitArea = CGSizeMake(44, 44)

extension UIButton {
    public override func hitTest(point: CGPoint, withEvent event: UIEvent?) -> UIView? {
        // if the button is hidden/disabled/transparent it can't be hit
        if self.hidden || !self.userInteractionEnabled || self.alpha < 0.01 { return nil }

        // increase the hit frame to be at least as big as `minimumHitArea`
        let buttonSize = self.bounds.size
        let widthToAdd = max(minimumHitArea.width - buttonSize.width, 0)
        let heightToAdd = max(minimumHitArea.height - buttonSize.height, 0)
        let largerFrame = CGRectInset(self.bounds, -widthToAdd / 2, -heightToAdd / 2)

        // perform hit test on larger frame
        return (CGRectContainsPoint(largerFrame, point)) ? self : nil
    }
}

Swift 3:

fileprivate let minimumHitArea = CGSize(width: 100, height: 100)

extension UIButton {
    open override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
        // if the button is hidden/disabled/transparent it can't be hit
        if self.isHidden || !self.isUserInteractionEnabled || self.alpha < 0.01 { return nil }

        // increase the hit frame to be at least as big as `minimumHitArea`
        let buttonSize = self.bounds.size
        let widthToAdd = max(minimumHitArea.width - buttonSize.width, 0)
        let heightToAdd = max(minimumHitArea.height - buttonSize.height, 0)
        let largerFrame = self.bounds.insetBy(dx: -widthToAdd / 2, dy: -heightToAdd / 2)

        // perform hit test on larger frame
        return (largerFrame.contains(point)) ? self : nil
    }
}

Solution 4:

You could also subclass UIButton or a custom UIView and override point(inside:with:) with something like:

Swift 3

override func point(inside point: CGPoint, with _: UIEvent?) -> Bool {
    let margin: CGFloat = 5
    let area = self.bounds.insetBy(dx: -margin, dy: -margin)
    return area.contains(point)
}

Objective-C

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {
    CGFloat margin = 5.0;
    CGRect area = CGRectInset(self.bounds, -margin, -margin);
    return CGRectContainsPoint(area, point);
}

Solution 5:

Here's Chase's UIButton+Extensions in Swift 3.0.

import UIKit

private var pTouchAreaEdgeInsets: UIEdgeInsets = .zero

extension UIButton {

    var touchAreaEdgeInsets: UIEdgeInsets {
        get {
            if let value = objc_getAssociatedObject(self, &pTouchAreaEdgeInsets) as? NSValue {
                var edgeInsets: UIEdgeInsets = .zero
                value.getValue(&edgeInsets)
                return edgeInsets
            }
            else {
                return .zero
            }
        }
        set(newValue) {
            var newValueCopy = newValue
            let objCType = NSValue(uiEdgeInsets: .zero).objCType
            let value = NSValue(&newValueCopy, withObjCType: objCType)
            objc_setAssociatedObject(self, &pTouchAreaEdgeInsets, value, .OBJC_ASSOCIATION_RETAIN)
        }
    }

    open override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
        if UIEdgeInsetsEqualToEdgeInsets(self.touchAreaEdgeInsets, .zero) || !self.isEnabled || self.isHidden {
            return super.point(inside: point, with: event)
        }

        let relativeFrame = self.bounds
        let hitFrame = UIEdgeInsetsInsetRect(relativeFrame, self.touchAreaEdgeInsets)

        return hitFrame.contains(point)
    }
}

To use it, you can:

button.touchAreaEdgeInsets = UIEdgeInsets(top: -10, left: -10, bottom: -10, right: -10)