FAB, a custom IBDesignable UIButton

FAB.h

//
//  FAB.h
//
//  Created by Kalpesh Talkar on 01/04/16.
//  Copyright © 2016 Kalpesh. All rights reserved.
//

#import <UIKit/UIKit.h>

// On click block
typedef void (^OnClick)();

@interface FAB : UIButton

// Init method
- (instancetype)initWithFrame:(CGRect)frame image:(UIImage *)image onClick:(OnClick)action;

@end

FAB.m

//
//  FAB.m
//
//  Created by Kalpesh Talkar on 01/04/16.
//  Copyright © 2016 Kalpesh. All rights reserved.
//

#import "FAB.h"

@interface FAB() {
    OnClick onClick;
}

@end

@implementation FAB

#pragma mark - Instance Methods
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    self = [super initWithCoder:aDecoder];
    if (self) {
        [self renderView];
    }
    return self;
}

- (instancetype)initWithFrame:(CGRect)frame image:(UIImage *)image onClick:(OnClick)action {
    self = [super initWithFrame:frame];
    if (self) {
        onClick = action;
        [self defaults];
        [self renderView];
        [self setImage:image forState:UIControlStateNormal];
    }
    return self;
}

- (void)drawRect:(CGRect)rect {
    [self renderView];
}

- (void)setNeedsLayout {
    [super setNeedsLayout];
    [self setNeedsDisplay];
}

- (void)prepareForInterfaceBuilder {
    [self renderView];
}

#pragma mark - Defaults
- (void)defaults {
    [self setTintColor:[UIColor whiteColor]];
    [self.titleLabel setFont:[UIFont systemFontOfSize:15]];
    [self setTitleColor:[self tintColor] forState:UIControlStateNormal];
    [self setTitleColor:[self highlightedColor] forState:UIControlStateHighlighted];
    [self setBackgroundColor:[UIColor redColor]];
    [self setBackgroundImage:[self imageWithColor:[UIColor lightGrayColor]] forState:UIControlStateDisabled];
    [self addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
}

#pragma mark - ButtonClicked
- (void)buttonClicked:(FAB *)fab {
    onClick();
}

#pragma mark - Highlighted Color
- (UIColor *)highlightedColor {
    UIColor *highlighted = [self titleColorForState:UIControlStateNormal];
    highlighted = [highlighted colorWithAlphaComponent:0.0];
    return highlighted;
}

#pragma mark - Render View
- (void)renderView {
    CGFloat size = self.frame.size.width/2;
    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:self.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerBottomLeft | UIRectCornerTopRight | UIRectCornerBottomRight) cornerRadii:CGSizeMake(size, size)];
    
    CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
    maskLayer.frame = self.bounds;
    maskLayer.path  = maskPath.CGPath;
    
    //self.layer.cornerRadius = self.frame.size.width/2;
    self.layer.shadowRadius = self.frame.size.width/2;
    self.layer.shadowColor = [UIColor blackColor].CGColor;
    self.layer.shadowOffset = CGSizeMake(1.0f, 1.0f);
    self.layer.shadowOpacity = 0.8f;
    //self.layer.masksToBounds = true;
    self.layer.mask = maskLayer;
}

#pragma mark - UIImage with UIColor
- (UIImage *)imageWithColor:(UIColor *)color {
    CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);
    
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return image;
}

@end