salesforce 零基础学习（六十三）Comparable实现Object列表数据的自定义排序

项目中通常有些需求为需要将某个sObject的数据列表按照某种规则排序显示到前台页面上，但是list上面的sort远远满足不了复杂的功能，此种情况需要自定义比较两个object大小的方法，所以需要创建Compare相关的类实现Comparable接口。

 需求：实现Goods__c列表排序，GoodsBrand__c为华为的按照价格升序排序，GoodsBrand__c为联想的按照价格降序排列。

public without sharing class ComparedGoods implements Comparable{
    private Goods__c goods{get;set;}
    
    private static final String GOODS_BRAND_HUAWEI = '华为';
    
    private static final String GOODS_BRAND_LIANXIANG = '联想';
    
    public ComparedGoods(Goods__c obj) {
        goods = obj;
    }
    
    public Integer compareTo(Object objectToCompareTo) {
            Goods__c comparedGoods = (Goods__c)objectToCompareTo;
            Integer comparedResult = 0;
            if(comparedGoods.GoodsBrand__c == GOODS_BRAND_HUAWEI) {
                if(goods.GoodsPrice__c > comparedGoods.GoodsPrice__c) {
                    comparedResult = 1;
                } else if(goods.GoodsPrice__c < comparedGoods.GoodsPrice__c) {
                    comparedResult = -1;
                }
            } else if(comparedGoods.GoodsBrand__c == GOODS_BRAND_LIANXIANG) {
                if(goods.GoodsPrice__c > comparedGoods.GoodsPrice__c) {
                    comparedResult = -1;
                } else if(goods.GoodsPrice__c == comparedGoods.GoodsPrice__c) {
                    comparedResult = 0;
                } 
                else if(goods.GoodsPrice__c < comparedGoods.GoodsPrice__c) {
                    comparedResult = 1;
                }
            }
            return comparedResult;
    }
}

用法：

总结：针对object需要比较大小的时候，可以实现Comparable接口，在其compareTo方法中实现比较的逻辑即可。此篇有错误的地方欢迎指正，有问题欢迎留言。