功能描述：提供导航标题，左右按钮及点击功能。

做法

新建一个类，继承自UIView。
在.h文件中提供外界创建方法，标题颜色属性

@interface PDtopBar : UIView

@property(nonatomic,strong)UIColor *titleColor;
@property(nonatomic,strong)UIColor *viewColor;   // 背景色
@property(nonatomic,assign)BOOL hidden;   //隐藏？

@property(nonatomic,strong)void(^gobackBlock)();   // 返回上一页block
@property(nonatomic,strong)void(^clickRightBtnBlock)();    // 点击右按钮block

// 提供外界创建方法
-(instancetype)initWithTitle:(NSString *)title rightBtnTitle:(NSString *)rightText;

@end

.m文件中，声明子控件

@interface PDtopBar()

@property(nonatomic,weak)UILabel *topTitleLabel;   // 标题

@property(nonatomic,weak)UIButton *backBtn;   // 左边的返回按钮

@property(nonatomic,weak)UIButton *rightBtn;   // 右边的按钮

@end

实现创建方法

-(instancetype)initWithTitle:(NSString *)title rightBtnTitle:(NSString *)rightText{
    
    if(self = [super init]){
        self.backgroundColor = [UIColor whiteColor];
        
        //位置，尺寸
        self.frame = CGRectMake(0, 20, screenW, 44);
        if(screenH == 812)
            self.frame = CGRectMake(0, 44, screenW, 44);    // 适配IphoneX
        
        UILabel *toplabel = [[UILabel alloc] Label_color3:Font18 text:title];
        toplabel.textAlignment = NSTextAlignmentCenter;
        [self addSubview:toplabel];
        _topTitleLabel = toplabel;
        [_topTitleLabel mas_makeConstraints:^(MASConstraintMaker *make) {
            make.centerY.equalTo(self.mas_centerY);
            make.centerX.equalTo(self.mas_centerX);
            make.width.equalTo(self.mas_width).multipliedBy(0.6);
        }];
        
        UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
        [btn addTarget:self action:@selector(clickBack) forControlEvents:UIControlEventTouchUpInside];
        [btn setImage:[UIImage imageNamed:@"back.png"] forState:UIControlStateNormal];
        [self addSubview:btn];
        _backBtn = btn;
        [_backBtn mas_makeConstraints:^(MASConstraintMaker *make) {
            make.left.equalTo(self.mas_left).offset(5);
            make.centerY.equalTo(_topTitleLabel.mas_centerY);
            make.height.equalTo(@20);
            make.width.equalTo(@50);
        }];
        
    if(rightText){
            UIButton *btn2 = [UIButton buttonWithType:UIButtonTypeCustom];
            btn2.titleLabel.font = Font16;
            [btn2 setTitleColor:Color333333 forState:UIControlStateNormal];
            [btn2 addTarget:self action:@selector(clickRight) forControlEvents:UIControlEventTouchUpInside];
            [self addSubview:btn2];
            _rightBtn = btn2;
            [_rightBtn mas_makeConstraints:^(MASConstraintMaker *make) {
                make.right.equalTo(self.mas_right).offset(-5);
                make.centerY.equalTo(_topTitleLabel.mas_centerY);
                make.height.equalTo(@20);
                make.width.equalTo(@50);
            }];
       }
    }
    return self;
}

点击事件处理

-(void)clickRight{
      if(self.clickRightBtnBlock)
          self.clickRightBtnBlock();
}

-(void)clickBack{
       if(self.gobackBlock)
          self.gobackBlock();
}

属性样式设置
标题颜色

-(void)setTitleColor:(UIColor *)titleColor{
    self.topTitleLabel.textColor =titleColor;
}

背景色

-(void)setViewColor:(UIColor *)viewColor{
    self.backgroundColor = viewColor;
}

隐藏属性

-(void)setHidden:(BOOL)hidden{
    self.hidden = hidden;
}

外界使用

创建时提供标题、右标题、左右按钮的代码block即可。

总结：比较简陋，只有基本的常用功能。请按需使用。