【界面UI】分页控件：道具列表的分页与滚动复用

---PageView 承载分页，每页 8 行
function MailList.build(win)
    local pv = GUI:PageView_Create(win, "mail_pages", 10, 40, 380, 300)
    GUI:PageView_setPageSize(pv, 8)
    local list = GUI:ListView_Create(win, "mail_items", 10, 40, 380, 300)
    MailList.pv = pv
    MailList.list = list
    MailList.perPage = 8
end

---翻页按钮与页码显示
function MailList.bindPager()
    GUI:addOnClickEvent(MailPage.prevBtn, function()
        MailList.jump(MailList.page - 1)
    end)
    GUI:addOnClickEvent(MailPage.nextBtn, function()
        MailList.jump(MailList.page + 1)
    end)
end

---列表项复用：只保留可视区的行控件
function MailList.render(page)
    local data = MailList.data
    local from = (page - 1) * MailList.perPage + 1
    local to = math.min(page * MailList.perPage, #data)
    for i = from, to do
        local row = MailList.pool[i - from + 1] or MailList.newRow()
        MailList.fill(row, data[i])
        MailList.show(row, (i - from) * 36)
    end
    MailList.hideRest(to - from + 1)
end