Odoo14中的逆计算inverse方法属性值用法——由compute字段的值逆向修改其依赖值

   #定义结束日期字段，结束日期由开始+持续，而设置结束日期，则需要自行计算出持续日期
    end_date = fields.Date(string="End Date", store=True,
                           compute='_get_end_date', inverse='_set_end_date')
    #"获取结束日期"事件的响应函数：计算出结束日期
    @api.depends('start_date', 'duration')
    def _get_end_date(self):
        for r in self:
            if not (r.start_date and r.duration):
                r.end_date = r.start_date
                continue
            start = fields.Datetime.from_string(r.start_date)
            duration = timedelta(days=r.duration, seconds=-1)
            r.end_date = start + duration

    #"设置结束日期"事件的响应函数：计算并设置持续时间
    def _set_end_date(self):
        for r in self:
            if not (r.start_date and r.end_date):
                continue
            start_date = fields.Datetime.from_string(r.start_date)
            end_date = fields.Datetime.from_string(r.end_date)
            r.duration = (end_date - start_date).days + 1