为UINavigationBar 写一个分类。UINavigationItem+correct_offset.h
转载 http://www.colabug.com/thread-1112420-1-1.html
#import
@interface UINavigationItem (correct_offset)
- ( void )addLeftBarButtonItem:( UIBarButtonItem *)leftBarButtonItem;
- ( void )addRightBarButtonItem:( UIBarButtonItem *)rightBarButtonItem;
@end
#import "UINavigationItem+correct_offset.h"
#define ios7 ([[[UIDevice currentDevice] systemVersion] floatValue]>= 7.0 ?YES:NO)
@implementation UINavigationItem (correct_offset)
- ( void )addLeftBarButtonItem:( UIBarButtonItem *)leftBarButtonItem
{
if ( ios7 ) {
// Add a spacer on when running lower than iOS 7.0
UIBarButtonItem *negativeSpacer = [[ UIBarButtonItem alloc ] initWithBarButtonSystemItem : UIBarButtonSystemItemFixedSpace
target : nil action : nil ];
negativeSpacer. width = - 20 ;
[ self setLeftBarButtonItems :[ NSArray arrayWithObjects :negativeSpacer, leftBarButtonItem, nil ]];
} else {
// Just set the UIBarButtonItem as you would normally
[ self setLeftBarButtonItem :leftBarButtonItem];
}
}
- ( void )addRightBarButtonItem:( UIBarButtonItem *)rightBarButtonItem
{
if ( ios7 ) {
// Add a spacer on when running lower than iOS 7.0
UIBarButtonItem *negativeSpacer = [[ UIBarButtonItem alloc ]
initWithBarButtonSystemItem : UIBarButtonSystemItemFixedSpace
target : nil action : nil ];
negativeSpacer. width = 10 ;
[ self setRightBarButtonItems :[ NSArray arrayWithObjects :negativeSpacer, rightBarButtonItem, nil ]];
} else {
// Just set the UIBarButtonItem as you would normally
[ self setRightBarButtonItem :rightBarButtonItem];
}
}
@end
在要设置返回按钮的UIViewController中按照如下使用。
[ self . navigationItem addLeftBarButtonItem: [ self creatBarItemWithAction : @selector (dismiss)]];
creatBarItemWithAction是我自己写的一个方法。
/**
* 退出视图。
*/
-( void )dismiss
{
[ self dismissViewControllerAnimated : YES completion : nil ];
}
/**
* 创建一个 UIBarButtonItem
*
* @param _action action
*
* @return UIBarButtonItem
*/
-( UIBarButtonItem *)creatBarItemWithAction:( SEL )_action{
UIButton * button = [ UIButton buttonWithType : UIButtonTypeCustom ];
[button setImage :[ UIImage imageNamed : @"backButton.png" ] forState : UIControlStateNormal ];
[button setFrame : CGRectMake ( 0 , 0 , 40 , 40 )];
[button addTarget : self action :_action forControlEvents : UIControlEventTouchUpInside ];
UIBarButtonItem * item = [[ UIBarButtonItem alloc ] initWithCustomView :button] ;
return item;
}
方式二：在创建自定义 UIBarButtonItem 的时候通过设置自定义view的图片偏移属性来做适配。
在要设置返回按钮的UIViewController中按照如下使用。
self . navigationItem . leftBarButtonItem = [ self creatBarItemWithAction : @selector (dismiss) solutiontwo : 2 ];
-( UIBarButtonItem *)creatBarItemWithAction:( SEL )_action solutiontwo:( NSInteger )index{
UIButton * button = [ UIButton buttonWithType : UIButtonTypeCustom ];
[button setImage :[ UIImage imageNamed : @"backButton.png" ] forState : UIControlStateNormal ];
[button setFrame : CGRectMake ( 0 , 0 , 40 , 40 )];
if ( ios7 ) {
[button setImageEdgeInsets : UIEdgeInsetsMake ( 0 , - 30 , 0 , 0 )];
}
else
{
[button setImageEdgeInsets : UIEdgeInsetsMake ( 0 , 0 , 0 , 0 )];
}
[button addTarget : self action :_action forControlEvents : UIControlEventTouchUpInside ];
UIBarButtonItem * item = [[ UIBarButtonItem alloc ] initWithCustomView :button] ;
return item;
}