一。自定义navigationbar
- (void)initNavigationBar{
[self.navigationController setNavigationBarHidden:YES];
UINavigationBar *bar = [[UINavigationBar alloc] initWithFrame:CGRectMake(, , , )];
[bar setBackgroundImage:[UIImage imageNamed:@"zhuche_bar2.png"] forBarMetrics:UIBarMetricsDefault];
UINavigationItem *item = [[UINavigationItem alloc] initWithTitle:nil];
UIButton *left = [UIButton buttonWithType:UIButtonTypeCustom];
[left setFrame:CGRectMake(, , , )];
[left setImage:[UIImage imageNamed:@"zhuche_back.png"] forState:UIControlStateNormal];
[left addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *leftButton = [[UIBarButtonItem alloc] initWithCustomView:left];
[item setLeftBarButtonItem:leftButton];
[bar pushNavigationItem:item animated:NO];
[self.view addSubview:bar];
}
- (void)back{
[self.navigationController popViewControllerAnimated:YES];
}
虽然可以解决自定义navigationbar的问题，左右按钮都可以替换，但是如果放在UITableViewController中，自定义的navigationbar会随着scrollview的滑动而滑动，不会像系统自带的navigationbar一样始终保持在屏幕最上方。那么我们可以有第二种解决方式，修改原来的navigationbar，其实就是改一下leftBarButtonItem或者rightBarButtonItem在navigationbar上面的位置：修改UIBarButtonItem 的边距。
二。修改UIBarButtonItem 的边距
@interface UINavigationItem (margin) @end @implementation UINavigationItem (margin) #if __IPHONE_OS_VERSION_MAX_ALLOWED > __IPHONE_6_1
- (void)setLeftBarButtonItem:(UIBarButtonItem *)_leftBarButtonItem
{
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)
{
UIBarButtonItem *negativeSeperator = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
negativeSeperator.width = -;//此处修改到边界的距离，请自行测试 if (_leftBarButtonItem)
{
[self setLeftBarButtonItems:@[negativeSeperator, _leftBarButtonItem]];
}
else
{
[self setLeftBarButtonItems:@[negativeSeperator]];
} }
else
{
[self setLeftBarButtonItem:_leftBarButtonItem animated:NO];
}
} - (void)setRightBarButtonItem:(UIBarButtonItem *)_rightBarButtonItem
{
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)
{
UIBarButtonItem *negativeSeperator = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
negativeSeperator.width = -;//此处修改到边界的距离，请自行测试 if (_rightBarButtonItem)
{
[self setRightBarButtonItems:@[negativeSeperator, _rightBarButtonItem]];
}
else
{
[self setRightBarButtonItems:@[negativeSeperator]];
} }
else
{
[self setRightBarButtonItem:_rightBarButtonItem animated:NO];
}
} #endif
@end
以上代码可以放置在主视图控制器的.m文件里面，@implementation ViewController的上面。
参考资料：http://blog.csdn.net/reylen/article/details/16338781；
http://blog.163.com/lhl_soft/blog/static/201750004201292043750125/；