var announce_div_id;
// ---公告拉取--- //
function announce_init(aid) {
    var xmlHttp;
    announce_div_id = aid;
    scrollText.init(announce_div_id, 50);
    scrollText.scrollUp();
}

// --- 滚动效果 --- //
function next(elem) {
    do {
        elem = elem.nextSibling;
    }
    while (elem && elem.nodeType != 1);
    return elem;
}

function first(elem) {
    elem = elem.firstChild;
    return elem && elem.nodeType != 1 ? next(elem) : elem;
}

var scrollText =
{
    init: function(scrollbox, speed) {
        this.boxID = scrollbox;
        this.scrollSpeed = speed || 50;
    },
    obj: function() {
        var scrollBox = document.getElementById(this.boxID);
        var appendBox = first(scrollBox).cloneNode(true);

        scrollBox.appendChild(appendBox);
        return {
            scrollBox: scrollBox,
            appendBox: appendBox,
            scrollSpeed: scrollText.scrollSpeed
        };
    },
    scrollUp: function() {
        var m = this.obj();
        var doTimeout;
        var doScr = setInterval(function() {
            if (m['appendBox'].offsetHeight <= m['scrollBox'].scrollTop) {
                m['scrollBox'].scrollTop -= m['appendBox'].offsetHeight;
            }
            else if (m['scrollBox'].scrollTop % m['scrollBox'].firstChild.firstChild.offsetHeight == 0) {
                clearInterval(doScr);
                doTimeout = setTimeout(function() {
                    scrollText.init(m['scrollBox'].id, m['scrollSpeed']);
                    scrollText.scrollUp();
                }, 5000);

                m['scrollBox'].scrollTop++;
            }
            else {
                m['scrollBox'].scrollTop++;
            }
        },
            			this.scrollSpeed
            		);

        m['scrollBox'].onmouseover = function() {
            clearInterval(doScr);
            clearTimeout(doTimeout);
        }

        m['scrollBox'].onmouseout = function() {
            clearInterval(doScr);
            scrollText.init(this.id, m['scrollSpeed']);
            scrollText.scrollUp();
        }
    }
}