/**

     leftItem

     */

    UIButton *leftbtn = [[UIButton alloc]initWithFrame:CGRectMake(, , , )];

    [leftbtn setImage:[UIImage imageNamed:@"public_back_n"] forState:UIControlStateNormal];

    [leftbtn addTarget:self action:@selector(clickBackItem) forControlEvents:UIControlEventTouchUpInside];

    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:leftbtn];

    UIBarButtonItem *negativeSpacer = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];

    negativeSpacer.width = ;// 右移  负左移

    self.navigationItem.leftBarButtonItems = @[negativeSpacer,self.navigationItem.leftBarButtonItem];

    /**

     rightItem

     */

    UIButton *rightbtn = [[UIButton alloc]initWithFrame:CGRectMake(, , , )];

    [rightbtn setImage:[UIImage imageNamed:@"public_appraise_icon"] forState:UIControlStateNormal];

    [rightbtn addTarget:self action:@selector(clickBackItem1) forControlEvents:UIControlEventTouchUpInside];

    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:rightbtn];

    UIBarButtonItem *rightnegativeSpacer = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];

    rightnegativeSpacer.width = ; //左移  负右移

    self.navigationItem.rightBarButtonItems = @[rightnegativeSpacer,self.navigationItem.rightBarButtonItem];