How do you set the font size on a UIBarButtonItem?

问题

I can't find a way to set the font size of the title in a custom UIBarButtonItem. The only way I can think of getting around this is to set it as an image which I would like to avoid. Any other suggestions?

回答1:

In a easy way, simply:

Objective-C:

NSUInteger fontSize = 20;
UIFont *font = [UIFont boldSystemFontOfSize:fontSize];
NSDictionary *attributes = @{NSFontAttributeName: font};

UIBarButtonItem *item = [[UIBarButtonItem alloc] init];

[item setTitle:@"Some Text"];
[item setTitleTextAttributes:attributes forState:UIControlStateNormal];

self.navigationItem.rightBarButtonItem = item;

Swift:

let fontSize:CGFloat = 20;
let font:UIFont = UIFont.boldSystemFont(ofSize: fontSize);
let attributes:[String : Any] = [NSFontAttributeName: font];

let item = UIBarButtonItem.init();

item.title = "Some Text";
item.setTitleTextAttributes(attributes, for: UIControlState.normal);

self.navigationItem.rightBarButtonItem = item;

回答2:

Create a UILabel and use -initWithCustomView:.

回答3:

As a concrete example of what KennyTM suggests, you create the UIBarButtonItem with something like the following (in code):

UILabel *txtLabel = [[UILabel alloc] initWithFrame:rect];
txtLabel.backgroundColor = [UIColor clearColor];
txtLabel.textColor = [UIColor lightGrayColor];
txtLabel.text = @"This is a custom label";
UIBarButtonItem *btnText = [[[UIBarButtonItem alloc] initWithCustomView:txtLabel] autorelease];

Then, you can add it as centered text on a UIToolbar (for instance) with the following:

UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:rect];
toolBar.barStyle = UIBarStyleBlackTranslucent;
UIBarButtonItem *flexSpace1 = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil] autorelease];
UIBarButtonItem *flexSpace2 = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil] autorelease];

[toolBar setItems:[NSArray arrayWithItems:flexSpace1, btnText, flexSpace2, nil]];

(of course, to get proper formatting, the rect used for initializing txtLabel and toolBar should be the proper sizes.... but that's another exercise!)

回答4:

[[UIBarButtonItem appearance]setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                                     [UIColor colorWithRed:245.0/255.0 green:245.0/255.0 blue:245.0/255.0 alpha:1.0], NSForegroundColorAttributeName,
                                                     [UIFont fontWithName:@"FONT-NAME" size:21.0], NSFontAttributeName, nil]
                                           forState:UIControlStateNormal];

来源：https://stackoverflow.com/questions/2720733/how-do-you-set-the-font-size-on-a-uibarbuttonitem

标签

iphone

uibarbuttonitem

font-size