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iphone - UITextView text selection and highlight jumping in iOS 8

I'm using UIMenuItem and UIMenuController to add a highlight feature to my UITextView, so the user can change the background color of the selected text, as shown in the pictures bellow:

  • Setected text in UITextView with the highlight feature available to the user:

Setected text in <code>UITextView</code>

  • Highlighted text in UITextView with a new background color, chosen by the user after tapping on the highlight feature: Highlighted text in <code>UITextView</code> with a new background color

In iOS 7 the following code is working perfectly to accomplish this task:

- (void)viewDidLoad {

    [super viewDidLoad];

    UIMenuItem *highlightMenuItem = [[UIMenuItem alloc] initWithTitle:@"Highlight" action:@selector(highlight)];
    [[UIMenuController sharedMenuController] setMenuItems:[NSArray arrayWithObject:highlightMenuItem]];
}

- (void)highlight {

    NSRange selectedTextRange = self.textView.selectedRange;

    [attributedString addAttribute:NSBackgroundColorAttributeName
                             value:[UIColor redColor]
                             range:selectedTextRange];

    // iOS 7 fix, NOT working in iOS 8 
    self.textView.scrollEnabled = NO;
    self.textView.attributedText = attributedString;
    self.textView.scrollEnabled = YES;
}

But in iOS 8 the text selection is jumping. When I use the highlight feature from the UIMenuItem and UIMenuController it jumps also to another UITextView offset.

How do I solve this problem in iOS 8?

See Question&Answers more detail:os

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1 Answer

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by (71.8m points)

I ended up solving my problem like this, and if someone else has a more elegant solution please let me know:

- (void)viewDidLoad {

    [super viewDidLoad];

    UIMenuItem *highlightMenuItem = [[UIMenuItem alloc] initWithTitle:@"Highlight" action:@selector(highlight)];
    [[UIMenuController sharedMenuController] setMenuItems:[NSArray arrayWithObject:highlightMenuItem]];

    float sysVer = [[[UIDevice currentDevice] systemVersion] floatValue];

    if (sysVer >= 8.0) {
        self.textView.layoutManager.allowsNonContiguousLayout = NO;
    } 
}

- (void)highlight {

    NSRange selectedTextRange = self.textView.selectedRange;

    [attributedString addAttribute:NSBackgroundColorAttributeName
                             value:[UIColor redColor]
                             range:selectedTextRange];

    float sysVer = [[[UIDevice currentDevice] systemVersion] floatValue];
    if (sysVer < 8.0) {
        // iOS 7 fix
        self.textView.scrollEnabled = NO;
        self.textView.attributedText = attributedString;
        self.textView.scrollEnabled = YES;
    } else {
        self.textView.attributedText = attributedString;
    }
}

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