Lined UITextView in IOS7

Question

I have a subclass of a UITextView (Custom Control DALinedTextView) where i draw lined text. It works perfect on iOS5 and iOS6 but on iOS7 it fails (text does not match lines).

   - (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetLineWidth(context, 1.0f);

    if (self.horizontalLineColor)
    {
        CGContextBeginPath(context);
        CGContextSetStrokeColorWithColor(context, self.horizontalLineColor.CGColor);

        // Create un-mutated floats outside of the for loop.
        // Reduces memory access.
        CGFloat baseOffset = 7.0f + self.font.descender;
        CGFloat screenScale = [UIScreen mainScreen].scale;
        CGFloat boundsX = self.bounds.origin.x;
        CGFloat boundsWidth = self.bounds.size.width;

        // Only draw lines that are visible on the screen.
        // (As opposed to throughout the entire view's contents)
        NSInteger firstVisibleLine = MAX(1, (self.contentOffset.y / self.font.lineHeight));
        NSInteger lastVisibleLine = ceilf((self.contentOffset.y + self.bounds.size.height) / self.font.lineHeight);
        for (NSInteger line = firstVisibleLine; line <= lastVisibleLine; ++line)
        {
            CGFloat linePointY = (baseOffset + (self.font.lineHeight * line));
            // Rounding the point to the nearest pixel.
            // Greatly reduces drawing time.
            CGFloat roundedLinePointY = roundf(linePointY * screenScale) / screenScale;
            CGContextMoveToPoint(context, boundsX, roundedLinePointY);
            CGContextAddLineToPoint(context, boundsWidth, roundedLinePointY);
        }
        CGContextClosePath(context);
        CGContextStrokePath(context);
    }

    if (self.verticalLineColor)
    {
        CGContextBeginPath(context);
        CGContextSetStrokeColorWithColor(context, self.verticalLineColor.CGColor);
        CGContextMoveToPoint(context, -1.0f, self.contentOffset.y);
        CGContextAddLineToPoint(context, -1.0f, self.contentOffset.y + self.bounds.size.height);
        CGContextClosePath(context);
        CGContextStrokePath(context);
    }
}

I know it's someting related to UIFont metrics..perphaps someone can help me out? I've change contentSize to intrinsicContentSize but it dos not work.

If i use systemFontOfSize it works perfectly, but with fontWithName it fails.

Answer 1

I've been struggling with this weird issue for quite a while, but finally stumbled upon a legit solution:

textView.layoutManager.usesFontLeading = NO;

This makes UITextView render text (almost) identically to UILabel.

Answer 2

Yes , i think you are using Custom Control DALinedTextView.

I am also facing a problem like you said in iOS7. Even you can't scroll that control correctly in iOS7.

First i used that control and now i leaved it and using built-in UITextView. :D

Perhaps , you need to change the font size and text margin or text padding of your textView.

Answer 3

check this link. It uses NSLayoutManagerDelegate, that is used in ios7. For iOS 7, the styleString approach no longer works. You have to use NSLayoutManagerDelegate, it is easy to use.

txtViewNote.layoutManager.delegate = self;
txtViewNote.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"textView_bg_lines"]];

- (CGFloat)layoutManager:(NSLayoutManager *)layoutManager lineSpacingAfterGlyphAtIndex:(NSUInteger)glyphIndex withProposedLineFragmentRect:(CGRect)rect
{
return 20.5; // For really wide spacing
}