Creating a left-arrow button (like UINavigationBar

Question

I'd love to create a "back" left-arrow-bezel button in a UIToolbar.

As far as I can tell, the only way to get one of these is to leave UINavigationController at default settings and it uses one for the left bar item. But there's no way I can find to create one as a UIBarButtonItem, so I can't make one in a standard UIToolbar, even though they're very similar to UINavigationBars.

I could manually create it with button images, but I can't find the source images anywhere. They have alpha-channel edges, so screenshotting and cutting won't get very versatile results.

Any ideas beyond screenshotting for every size and color scheme I intend to use?

Update: PLEASE STOP dodging the question and suggesting that I shouldn't be asking this and should be using UINavigationBar. My app is Instapaper Pro. It shows only a bottom toolbar (to save space and maximize readable content area), and I wish to put a left-arrow-shaped Back button in the bottom.

Telling me that I shouldn't need to do this is not an answer and certainly doesn't deserve a bounty.

Answer 1

I was trying to do the same thing, but I wanted the back button to be in the navigation bar. (I actually needed a back button, that would do more than only going back, so I had to use the leftBarButtonItem property). I tried what AndrewS suggested, but in the navigation bar it wouldn't look the way it should, as the UIButton was kind of casted to a UIBarButtonItem.

But I found a way to work around this. I actually just put a UIView under the UIButton and set the customView for the UIBarButtonItem. Here is the code, if somebody needs it:

// initialize button and button view
UIButton *backButton = [UIButton buttonWithType:101];
UIView *backButtonView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, backButton.frame.size.width, backButton.frame.size.height)];

[backButton addTarget:self action:@selector(backButtonTouched:) forControlEvents:UIControlEventTouchUpInside];
[backButton setTitle:@"Back" forState:UIControlStateNormal];
[backButtonView addSubview:backButton];

// set buttonview as custom view for bar button item
UIBarButtonItem *backButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButtonView];
self.navigationItem.leftBarButtonItem = backButtonItem;

// push item to navigationbar items
[self.navigationController.navigationBar setItems:[NSArray arrayWithObject:backButtonItem]];

Answer 2

Try this. I am sure you do not need a back button image to create one such.

UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back"
                                                               style:UIBarButtonItemStyleBordered
                                                              target:self
                                                              action:@selector(yourSelectorGoesHere:)];
self.navigationItem.backBarButtonItem = backButton;

That's all you have to do :)

Answer 3

Well, you don't have to have a different button for every size, you can use [UIImage stretchableImageWithLeftCapWidth:topCapHeight:], but the only thing I've found is custom images.

Answer 4

Example in Swift 3, with a previous and a next button in the top right.

let prevButtonItem = UIBarButtonItem(title: "\u{25C0}", style: .plain, target: self, action: #selector(prevButtonTapped))
let nextButtonItem = UIBarButtonItem(title: "\u{25B6}", style: .plain, target: self, action: #selector(nextButtonTapped))
self.navigationItem.rightBarButtonItems = [nextButtonItem, prevButtonItem]

Answer 5

If you don't want to bother with image files, the arrow shape can be drawn in a UIView subclass with the following code:

- (void)drawRect:(CGRect)rect {
    float width = rect.size.width;
    float height = rect.size.height;
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextBeginPath(context);
    CGContextMoveToPoint(context, width * 5.0/6.0, height * 0.0/10.0);
    CGContextAddLineToPoint(context, width * 0.0/6.0, height * 5.0/10.0);
    CGContextAddLineToPoint(context, width * 5.0/6.0, height * 10.0/10.0);
    CGContextAddLineToPoint(context, width * 6.0/6.0, height * 9.0/10.0);
    CGContextAddLineToPoint(context, width * 2.0/6.0, height * 5.0/10.0);
    CGContextAddLineToPoint(context, width * 6.0/6.0, height * 1.0/10.0);
    CGContextClosePath(context);

    CGContextSetFillColorWithColor(context, [UIColor blackColor].CGColor);
    CGContextFillPath(context);
}

where the arrow view is proportional to a width of 6.0 and a height of 10.0

Answer 6

It's easy to do with Interface Builder in Xcode 5.x

• use Toolbar and Bar Button Item from Object library

  

• in button's Attributes inspector edit Image section with your back button image

  

Done!