iOS: UITableView selection (row highlight)

// Multiple selections

self.tableView.allowsMultipleSelection = YES;

// Transparent "highlight" list

self.tableView.allowsSelection = NO;

UITableViewDelegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // ...
}

iOS: Tex with various colors or formats

Objective C

- (NSAttributedString*)_text

{

    NSString* differentColorText = @"differentColorText";

    

    NSString* fullText = [NSString stringWithFormat:@"some text %@ some more text", differentColorText];

    

    NSMutableAttributedString *string = [[NSMutableAttributedString alloc]initWithString:fullText];

    

    NSRange range = [fullText rangeOfString: differentColorText];

    

    [string addAttribute:NSForegroundColorAttributeName

                   value:[UIColor redColor]

                   range:range];

    [string addAttribute:NSFontAttributeName 

                   value:[UIFont boldSystemFontOfSize:12]       

                   range: range];

    

    return string;

}

[self.label setAttributedText:[self _text]];

Swift

let text = "some text"

let fullText = "something else \(text)"

let range = (fullText as NSString).range(of: text)

        

let attributedText = NSMutableAttributedString(string: fullText)

attributedText.addAttribute(NSAttributedStringKey.font, value: UIFont.boldSystemFont(ofSize: 17), range: range)

        

field.attributedText = attributedText

iOS: UITextField with image on its right

Interface

IB_DESIGNABLE

@interface MyDropDownTextField : MyTextField

@property (nonatomic, strong) IBInspectable UIImage* rightViewImage;

@end

Implementation

#import "MyDropDownTextField.h"

@implementation MyDropDownTextField

- (void)awakeFromNib

{

    [super awakeFromNib];

    

    self.backgroundColor = [UIColor clearColor];

    self.rightViewMode = UITextFieldViewModeAlways;

    self.rightView = [[UIImageView alloc] initWithImage:self.rightViewImage];

    CGFloat height = self.frame.size.height;

    CGFloat y = (height - 6)/2;

    self.rightView.frame = CGRectMake(self.rightView.frame.origin.x, y, 9, 6);

}

- (CGRect) rightViewRectForBounds:(CGRect)bounds {

    

    CGRect textRect = [super rightViewRectForBounds:bounds];

    textRect.origin.x -= 10;

    return textRect;

}

@end

iOS: UIScrollView remove space saved for NavigationBar

self.automaticallyAdjustsScrollViewInsets = NO;

iOS: UITableView remove separator line

Objective C

self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;

Swift

tableView.separatorStyle = .none

iOS: Constraint animation

I wanted to animate a floating bar.

- (void)viewDidLoad
{
[super viewDidLoad];

self.floatingBar.hidden = YES;

    for (NSLayoutConstraint* contraint in self.view.constraints) {

        if ([contraint.identifier isEqualToString:@"top"]) {

            contraint.constant = -65 - self.floatingBar.frame.size.height;

            break;

        }

    }

...

}

#pragma mark - UIScrollViewDelegate

- (void)scrollViewDidScroll:(UIScrollView *)scrollView

{

    CGPoint offset = scrollView.contentOffset;

    

    if (offset.y < 400*) {

        if (!self.floatingBar.hidden) {

            self.floatingBar.hidden = YES;

            for (NSLayoutConstraint* contraint in self.view.constraints) {

                if ([contraint.identifier isEqualToString:@"top"])** {

                    contraint.constant = -65*** - self.floatingBar.frame.size.height;

                    break;

                }

            }

        }

        

    } else if (offset.y > 400) {

        if (self.floatingBar.hidden) {

            self.floatingBar.hidden = NO;

            

            [self.view layoutIfNeeded];

            

            [UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{

                

                for (NSLayoutConstraint* contraint in self.view.constraints) {

                    if ([contraint.identifier isEqualToString:@"top"]) {

                        contraint.constant = -65;

                        break;

                    }

                }

                

                [self.view layoutIfNeeded];

                

            } completion:^(BOOL finished) {

                

            }];

        }

    }

}

* 400 was my threshhold

** Name of my constraint (identifier I used in interface builder)

*** I wanted my bar to be at the top of the window (under status bar and navigation bar)