UIBarButtonSystemItemFlexibleSpace - ios

Question

Apple docs have this to say:
UIBarButtonSystemItemFlexibleSpace
Blank space to add between other items. The space is distributed equally between the other items. Other item properties are ignored when this value is set.
That's a little vague (exactly what space is distributed equally?) So I wrote a test method:
-(void) createToolbar {
BOOL stuffInTopLeftCorner = NO;
UIToolbar* bar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 1024, 44)];
self.bar = bar;
[self addSubview:bar];
UILabel* titleLabel = [[UILabel alloc]initWithFrame:CGRectZero];
titleLabel.text = #"Centered title";
titleLabel.font = [UIFont systemFontOfSize:30];
[titleLabel sizeToFit];
CGSize titleSize = [titleLabel bounds].size;
NSLog(#"titleSize is %g %g", titleSize.width, titleSize.height);
UIBarButtonItem* titleItem = [[UIBarButtonItem alloc]initWithCustomView:titleLabel];
UIBarButtonItem* flexibleSpace = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UILabel* leftLabel = [[UILabel alloc]initWithFrame:CGRectZero];
leftLabel.text = #"Stuff in top left corner";
leftLabel.font = [UIFont systemFontOfSize:30];
[leftLabel sizeToFit];
UIBarButtonItem* topLeftCornerItem = [[UIBarButtonItem alloc]initWithCustomView:leftLabel];
NSMutableArray* items = [NSMutableArray arrayWithObjects: flexibleSpace, titleItem, flexibleSpace, nil];
if (stuffInTopLeftCorner) {
[items insertObject:topLeftCornerItem atIndex:0];
}
bar.items = items;
}
Here is what it looks like with the code as above:
And here is what it looks like if I change stuffInTopLeftCorner to YES:
It appears that adding something to the left of the title did not cause said title to move at all.
My question is -- does that mean it will always center the title, regardless of what goes on either side of it?

Answer 1

As best I can tell, yes, it always centers the title, assuming that is possible.