自定义UIBarButtonItem

//单个自定义按钮

 UIButton *button =[UIButton buttonWithType:UIButtonTypeCustom];

    button.frame =CGRectMake(0, 0, 50, 50);

    UIBarButtonItem*Button = [[UIBarButtonItem alloc] initWithCustomView:button];

    self.navigationItem.leftBarButtonItem = Button;

//多个按钮

    UIBarButtonItem *btn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemPlay target:self action:@selector(click:)];

    UIBarButtonItem btnOne = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemPause target:self action:@selector(click1:)];

    [self.navigationItem setRightBarButtonItems:[NSArray arrayWithObjects:btn,btnOne,nil]];

//自定义View上随意放置button

  UIView *view = [[UIView alloc]initWithFrame:CGRectMake(kWidth * 4 / 5, 0, 75, 30)];

    //分享按钮

    UIButton *sharebutton = [UIButton buttonWithType:(UIButtonTypeCustom)];

    sharebutton.frame =  CGRectMake(5, 0, 30, 30);

    [view addSubview:sharebutton];

    //收藏按钮

    self.collectbutton = [UIButton buttonWithType:(UIButtonTypeCustom)];

    self.collectbutton.frame = CGRectMake(45, 0, 30, 30);

    [view addSubview:self.collectbutton];

    UIBarButtonItem *collectItem = [[UIBarButtonItem alloc] initWithCustomView:view];

    self.navigationItem.rightBarButtonItem = collectItem;