UINavigationItem centering the title

Question

I have a navigationBar with both Left and Right bar buttons on each side. I have a customTitlelabel which I set as the titleView of the UINavigationItem.

[self.navigationItem setTitleView:customTitleLabel];

All is fine now. The problem, the size of the rightbarButton is dynamic based on the input I get in one of the text fields.

Therefore the title is automatically centered based on the available space between the buttons.

how can i set the title to a fixed position?

Answer 1

Setting the titleView property of the nav bar works just fine - no need to subclass or alter any frames other than those of your custom view.

The trick to getting it centered relative to the overall width of UINavigationBar is to:

1. set the width of your view according to the size of the text
2. set the alignment to centered and
3. set the autoresizingmask so it gets resized to the available space

Here's some example code that creates a custom titleView with a label which remains centred in UINavigationBar irrespective of orientation, left or right barbutton width:

self.title = @"My Centered Nav Title";

// Init views with rects with height and y pos
CGFloat titleHeight = self.navigationController.navigationBar.frame.size.height;
UIView *titleView = [[UIView alloc] initWithFrame:CGRectZero];
UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectZero];

// Set font for sizing width
titleLabel.font = [UIFont boldSystemFontOfSize:20.f];

// Set the width of the views according to the text size
CGFloat desiredWidth = [self.title sizeWithFont:titleLabel.font
                            constrainedToSize:CGSizeMake([[UIScreen mainScreen] applicationFrame].size.width, titleLabel.frame.size.height)
                                lineBreakMode:UILineBreakModeCharacterWrap].width;

CGRect frame;

frame = titleLabel.frame;
frame.size.height = titleHeight;
frame.size.width = desiredWidth;
titleLabel.frame = frame;

frame = titleView.frame;
frame.size.height = titleHeight;
frame.size.width = desiredWidth;
titleView.frame = frame;

// Ensure text is on one line, centered and truncates if the bounds are restricted
titleLabel.numberOfLines = 1;
titleLabel.lineBreakMode = UILineBreakModeTailTruncation;
titleLabel.textAlignment = NSTextAlignmentCenter;

// Use autoresizing to restrict the bounds to the area that the titleview allows
titleView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
titleView.autoresizesSubviews = YES;
titleLabel.autoresizingMask = titleView.autoresizingMask;

// Set the text
titleLabel.text = self.title;

// Add as the nav bar's titleview
[titleView addSubview:titleLabel];
self.navigationItem.titleView = titleView;