UIToolbar left and right paddings are initially negative - ios

Question

I'm struggling with UIToolbar's strange behaviour in iOS7+ iPhone application.
Here's how I created it:
//toolbar
self.bottomToolbar=[[UIToolbar alloc] initWithFrame:CGRectMake(0.0, self.view.bounds.size.height-44.0, self.view.bounds.size.width, 44.0)];
self.bottomToolbar.autoresizingMask=(UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleWidth);
[MKUIHelper toolbar:self.bottomToolbar setBarStyle:MKBarStyleWhite];
self.bottomToolbar.items=#[];
[self.view addSubview:self.bottomToolbar];
When I need to update it I'm calling (actually updating only one of its items but this does not matter):
-(void)updateToolbar
{
UIBarButtonItem *doneBarButtonItem=[[UIBarButtonItem alloc] initWithTitle:#"done" style:UIBarButtonItemStylePlain target:self action:#selector(backButtonDidPress:)];
doneBarButtonItem.tintColor=MK_Color_Green;
UIBarButtonItem *clearBarButtonItem=[[UIBarButtonItem alloc] initWithTitle:#"clear" style:UIBarButtonItemStylePlain target:self action:#selector(clearButtonDidPress:)];
clearBarButtonItem.tintColor=MK_Color_Pink;
UIBarButtonItem *spaceBetweenBackAndQuantity=[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIBarButtonItem *spaceBetweenQuantityAndClear=[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIBarButtonItem *quantityItem=[self quantityBarButtonItem];
self.bottomToolbar.items=[NSArray arrayWithObjects:doneBarButtonItem, spaceBetweenBackAndQuantity, quantityItem, spaceBetweenQuantityAndClear, clearBarButtonItem, nil];
[self.rootViewController reloadToolbar];
}
Both UIBarButtonItem objects that was created using initWithTitle:.. have negative left and right paddings somehow. It can be roughly fixed by adding additional fixed space type UIBarButtonItems to both sides of the items array. In other words: compensate strange initial left and right paddings with fixed space type UIBarButtonItems.
Help me someone, please. What causes such strange effect? How can I get rid of this strange padding?
Here's how it looks like:

Answer 1

If you set the width of barButtons to correct width, you may be able to work around this.
- (UIBarButtonItem *)barButtonWithTitle:(NSString *)title action:(SEL)action {
UIBarButtonItem *barButtonItem = [[[UIBarButtonItem alloc] initWithTitle:title style:UIBarButtonItemStylePlain target:self action:action] autorelease];
UIButton *button = [UIButton buttonWithType: UIButtonTypeCustom];
[button setTitle:title forState: UIControlStateNormal];
[button sizeToFit];
CGSize size = button.bounds.size;
[barButtonItem setWidth:size.width];
return barButtonItem;
}