ios - How to change UITableViewRowAction title color?

Question

Am using UITableViewRowAction in "editActionsForRowAtIndexPath" method. I can change the backgroundcolor of UITableViewRowAction, but am not able to change the title color. But I would like to change the color of the UITableViewRowAction. Any inputs on this regard will be appreciable.

Answer 1

There is one way that can achieve what you are looking for. But it is little tricky though.

Example of result:

The idea of this trick is that you can actually modify background color. This means that you can set UIColor's +colorWithPatternImage: and set an bitmap image that match desired styling. This can be achieved either by creating image using graphic editor or by rendering it using for example Core Graphics. The only problem with this solution is, that you have to mimic original title length with you specific text attributes to make it work properly and also you must set title for table view row action as string of white spaces so that table view cell will prepare enough space for you "custom action button". Creating static png assets in photoshop may be inappropriate if you use variable cell rows.

This is category for NSString that creates string of empty spaces that will create space for your custom button and second will generate bitmap image that will be placed as background pattern image. For parameters you must set text attributes for original title, that is basically @{NSFontAttributeName: [UIFont systemFontOfSize:18]}, than your desired text attributes. Maybe there is better way to achieve this :)

@implementation NSString (WhiteSpace)

- (NSString *)whitespaceReplacementWithSystemAttributes:(NSDictionary *)systemAttributes newAttributes:(NSDictionary *)newAttributes
{
    NSString *stringTitle = self;
    NSMutableString *stringTitleWS = [[NSMutableString alloc] initWithString:@""];

    CGFloat diff = 0;
    CGSize  stringTitleSize = [stringTitle sizeWithAttributes:newAttributes];
    CGSize stringTitleWSSize;
    NSDictionary *originalAttributes = systemAttributes;
    do {
        [stringTitleWS appendString:@" "];
        stringTitleWSSize = [stringTitleWS sizeWithAttributes:originalAttributes];
        diff = (stringTitleSize.width - stringTitleWSSize.width);
        if (diff <= 1.5) {
            break;
        }
    }
    while (diff > 0);

    return [stringTitleWS copy];
}

@end

Second important part is code that renders bitmap that can be used as pattern image for UITableViewRowAction's backgroundColor.

- (UIImage *)imageForTableViewRowActionWithTitle:(NSString *)title textAttributes:(NSDictionary *)attributes backgroundColor:(UIColor *)color cellHeight:(CGFloat)cellHeight
{
    NSString *titleString = title;
    NSDictionary *originalAttributes = @{NSFontAttributeName: [UIFont systemFontOfSize:18]};
    CGSize originalSize = [titleString sizeWithAttributes:originalAttributes];
    CGSize newSize = CGSizeMake(originalSize.width + kSystemTextPadding + kSystemTextPadding, originalSize.height);
    CGRect drawingRect = CGRectIntegral(CGRectMake(0, 0, newSize.width, cellHeight));
    UIGraphicsBeginImageContextWithOptions(drawingRect.size, YES, [UIScreen mainScreen].nativeScale);
    CGContextRef contextRef = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(contextRef, color.CGColor);
    CGContextFillRect(contextRef, drawingRect);

    UILabel *label = [[UILabel alloc] initWithFrame:drawingRect];
    label.textAlignment = NSTextAlignmentCenter;
    label.attributedText = [[NSAttributedString alloc] initWithString:title attributes:attributes];
    [label drawTextInRect:drawingRect];

    //This is other way how to render string 
    //    CGSize size = [titleString sizeWithAttributes:attributes];
    //    CGFloat x =  (drawingRect.size.width - size.width)/2;
    //    CGFloat y =  (drawingRect.size.height - size.height)/2;
    //    drawingRect.origin = CGPointMake(x, y);
    //    [titleString drawInRect:drawingRect withAttributes:attributes];

    UIImage *returningImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return returningImage;
}

And then when you are creating your row action you can do something like this:

NSDictionary *systemAttributes = @{ NSFontAttributeName: [UIFont systemFontOfSize:18] };
NSDictionary *newAttributes = @{NSFontAttributeName: [UIFont fontWithName:@"Any font" size:15]};
NSString *actionTitle = @"Delete";
NSString *titleWhiteSpaced = [actionTitle whitespaceReplacementWithSystemAttributes:systemTextFontAttributes newAttributes:newAttributes];
UITableViewRowAction *rowAction = [UITableViewRowAction rowActionWithStyle:UITableViewRowActionStyleDefault title:titleWhiteSpaced handle:NULL];
UIImage *patternImage = [self imageForTableViewRowActionWithTitle:actionTitle textAttributes:newAttributes backgroundColor:[UIColor redColor] cellHeight:50];
rowAction.backgroundColor = [UIColor colorWithPatternImage:patternImage]; 

This solution is obviously hacky but you can achieve desired results without using private APIs and in future if something breaks, this will not break your app. Only button will look inappropriate.

Example of result:

This code has of course a lot of space for improvements, any suggestions are appreciated.