How to make the Navigation Bar of an UINavigationC

问题:

Is there any way to make the default navigation bar of an UINavigationController display at the bottom instead of the top? I know that there is an UIToolbar that can be displayed at the bottom, but that one is specific to each view and does not carry the "back" button.

回答1:

If you create your view using a NIB, then it is rather simple - select navigation bar in attributes->bottom bar. If not then you should access navigation bar directly and change its coordinates. In your view controller:

CGRect oldRect = self.navigationController.navigationBar.frame;
self.navigationController.navigationBar.frame = CGRectMake(x, y, oldRect.width, oldRect.height);

where x and y are coordinates to place your navigation bar.

回答2:

Try this :

bottomNav = [[UINavigationBar alloc] initWithFrame:CGRectMake(0.0,  self.view.frame.size.height - 20, self.view.frame.size.width, 44.0)];  
bottomNav.barStyle = UIBarStyleBlackOpaque;  
[self.parentViewController.view addSubview:bottomNav];  

回答3:

I think you can but i don't think it will approved by Apple

@implementation UINavigationBar (CustomBar)
- (void)drawRect:(CGRect)rect {
    self.frame = CGRectMake(0, 436, 320, 44);

}

回答4:

Here is the swift version:

var bottomNav = UINavigationBar(x: 0, y: view.frame.size.height - 20, w: view.frame.size.width, h: 44)
bottomNav.barStyle = UIBarStyle.Black
parentViewController?.view.addSubview(bottomNav)