Masonry的使用

参考：http://www.jianshu.com/p/10a250cc5018/
http://www.cnblogs.com/soley/p/5553448.html
总结：

  [label1 mas_makeConstraints:^(MASConstraintMaker *make) {
        make.width.mas_equalTo(50);
        make.height.mas_equalTo(25);
        make.left.equalTo(self.firstCellContentView).offset(leftSpace);
        make.centerY.equalTo(self.firstCellContentView.mas_centerY);
//1.make:该label1对象
//2.**.width:设置该对象的宽       **.mas_centerY:获取该对象的中心y值
//3.equalTo 和谁做参考       mas_equalTo：设置某个值
    }];

  //titleLabel
    UILabel *titleLabel = [[UILabel alloc]init];
    titleLabel.font = [UIFont systemFontOfSize:20];
    titleLabel.textColor =KBlackColor;
    titleLabel.text = @"学长帮用户协议细则";
     [self.view addSubview:titleLabel];
    
    [titleLabel mas_makeConstraints:^(MASConstraintMaker *make) {
//        make.left.mas_equalTo(100);
        make.centerX.equalTo(self.view.mas_centerX);
        make.top.mas_equalTo(130);
        make.width.mas_equalTo(200);
        make.height.mas_equalTo(20);

    }];

注意：先将titleLabel对象添加到父类在设置masonry；