方案一：利用UINavigationBar 自带的布局item（Fixed space Bar Button Item）来适配ios7. 其实就是在原来返回按钮的位置上在多加一个占位的Item

为UINavigationBar 写一个分类。UINavigationItem+correct_offset.h

#import <UIKit/UIKit.h>

@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 = [[UIBarButtonItemalloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace

                                                                                       target:nilaction:nil];

        negativeSpacer.width = -20;

        [self setLeftBarButtonItems:[NSArrayarrayWithObjects: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 = [[UIBarButtonItemalloc]

                                           initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace

                                           target:nilaction:nil];

        negativeSpacer.width = 10;

        [self setRightBarButtonItems:[NSArrayarrayWithObjects: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.navigationItemaddLeftBarButtonItem:[self creatBarItemWithAction:@selector(dismiss)]];

creatBarItemWithAction是我自己写的一个方法。

/**

 *  退出视图。

 */

-(void)dismiss

{

    [selfdismissViewControllerAnimated:YEScompletion:nil];

}

/**

 *  创建一个UIBarButtonItem

 *

 *  @param _action action

 *

 *  @return UIBarButtonItem

 */

-(UIBarButtonItem*)creatBarItemWithAction:(SEL)_action{

    UIButton* button = [UIButtonbuttonWithType:UIButtonTypeCustom];

    [button setImage:[UIImageimageNamed:@"backButton.png"]forState:UIControlStateNormal];

    [button setFrame:CGRectMake(0,0,40,40)];

    [button addTarget:selfaction:_actionforControlEvents:UIControlEventTouchUpInside];

    UIBarButtonItem* item = [[UIBarButtonItemalloc]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 = [selfcreatBarItemWithAction:@selector(dismiss)solutiontwo:2];

-(UIBarButtonItem*)creatBarItemWithAction:(SEL)_action solutiontwo:(NSInteger)index{

    UIButton* button = [UIButtonbuttonWithType:UIButtonTypeCustom];

    [button setImage:[UIImageimageNamed:@"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:selfaction:_actionforControlEvents:UIControlEventTouchUpInside];

    UIBarButtonItem* item = [[UIBarButtonItemalloc]initWithCustomView:button] ;

    return item;

}