Generic loading view: UIView with centred UIActivityViewIndicator

LoadingView.h

#import <UIKit/UIKit.h>

@interface LoadingView : UIView

@property (nonatomic, weak, readonly) UILabel *loadingLabel;
@property (nonatomic, weak, readonly) UIActivityIndicatorView *activityIndicator;

@end

LoadingView.m

#import "LoadingView.h"

@interface LoadingView ()
@property (nonatomic, weak) UILabel *loadingLabel;
@property (nonatomic, weak) UIActivityIndicatorView *activityIndicator;
@end

@implementation LoadingView

- (instancetype)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        UILabel *label = [[UILabel alloc] initWithFrame:CGRectZero];
        label.translatesAutoresizingMaskIntoConstraints = NO;
        label.text = NSLocalizedString(@"Loading...", nil);
        label.backgroundColor = [UIColor clearColor];
        label.shadowOffset = CGSizeMake(0.0f, 1.0f);
        label.shadowColor = [UIColor whiteColor];
        [label sizeToFit];
        [self addSubview:label];
       
        UIActivityIndicatorView *indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
        indicator.translatesAutoresizingMaskIntoConstraints = NO;
        [indicator startAnimating];
        [self addSubview:indicator];
       
        self.loadingLabel = label;
        self.activityIndicator = indicator;
       
        [self addConstraint:[NSLayoutConstraint constraintWithItem:indicator
                                                         attribute:NSLayoutAttributeCenterX
                                                         relatedBy:NSLayoutRelationEqual
                                                            toItem:self
                                                         attribute:NSLayoutAttributeCenterX
                                                        multiplier:1
                                                          constant:0]];
       
        [self addConstraint:[NSLayoutConstraint constraintWithItem:indicator
                                                         attribute:NSLayoutAttributeBottom
                                                         relatedBy:NSLayoutRelationEqual
                                                            toItem:self
                                                         attribute:NSLayoutAttributeCenterY
                                                        multiplier:1
                                                          constant:-10]];
       
        [self addConstraint:[NSLayoutConstraint constraintWithItem:label
                                                         attribute:NSLayoutAttributeCenterX
                                                         relatedBy:NSLayoutRelationEqual
                                                            toItem:self
                                                         attribute:NSLayoutAttributeCenterX
                                                        multiplier:1
                                                          constant:0]];
       
        [self addConstraint:[NSLayoutConstraint constraintWithItem:label
                                                         attribute:NSLayoutAttributeTop
                                                         relatedBy:NSLayoutRelationEqual
                                                            toItem:self
                                                         attribute:NSLayoutAttributeCenterY
                                                        multiplier:1
                                                          constant:10]];
    }
    return self;
}

- (void)layoutSubviews
{
    [self.loadingLabel sizeToFit];
    [super layoutSubviews];
}

@end