获取ListView滚动精确值

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项目需求要根据滚动位置,对title实现渐隐渐现效果,因此想获取ListView滚动时的精确位置。在网上找了很多都不能达到要求,千篇一律只有获取ListView滚动到某个item的高度整个的高度,例如:item高度为30,获得值只有0,30,60,90…在找寻中发现了ScrollView重写onScrollChanged可实现需求,于是在ListView中仿照重写onScrollChanged却没有作用。最后终于找到一种方法实现,特此分享给大家。

本文参考文:http://www.2cto.com/kf/201507/416142.html布局文件就略写了,只有个ListView,直接上核心代码:
    //初始化控件    mlistview = (ListView) findViewById(R.id.mylistview);    String[] datas=new String[]{"11111","222222","333333","11111","222222","333333","11111","222222","333333"                ,"11111","222222","333333","11111","222222","333333","11111","222222","333333"                ,"11111","222222","333333","11111","222222","333333","11111","222222","333333"                ,"11111","222222","333333","11111","222222","333333","11111","222222","333333"                ,"11111","222222","333333","11111","222222","333333","11111","222222","333333"};        mlistview.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, datas));        mlistview.setOnScrollListener(new AbsListView.OnScrollListener() {            private SparseArray<ItemRecod> recordSp = new SparseArray(0);            private int mCurrentfirstVisibleItem = 0;            @Override            public void onScrollStateChanged(AbsListView view, int scrollState) {            }            @Override            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {                mCurrentfirstVisibleItem = firstVisibleItem;                View firstView = view.getChildAt(0);                if (null != firstView) {                    ItemRecod itemRecord = recordSp.get(firstVisibleItem);                    if (null == itemRecord) {                        itemRecord = new ItemRecod();                    }                    //item高度                    itemRecord.height = firstView.getHeight();                    //滑动位置距顶部距离(负值)                    itemRecord.top = firstView.getTop();                    recordSp.append(firstVisibleItem, itemRecord);                }                Log.d("onScroll", getScrollY() + "");            }            //获取滚动精确值            private int getScrollY() {                int height = 0;                for (int i = 0; i < mCurrentfirstVisibleItem; i++) {                    ItemRecod itemRecod = recordSp.get(i);                    height += itemRecod.height;                }                ItemRecod itemRecod = recordSp.get(mCurrentfirstVisibleItem);                if (null == itemRecod) {                    itemRecod = new ItemRecod();                }                return height - itemRecod.top;            }            class ItemRecod {                int height = 0;                int top = 0;            }        });
这样 getScrollY()就可以获取ListView滚动的精确位置了,希望此文也能帮到有同样需求的人。
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