查找回收者视图中的第一个可见项目是否为列表中的第一项 [英] Find if the first visible item in the recycler view is the first item of the list or not

问题描述

我有一个包含13个数据项的回收站视图.我想找出列表中的第一项是否可见?

I have a recycler view with 13 data items. I want to find out whether the first item of my list is visible or not?

我知道诸如 findFirstVisibleItemPosition 和 findLastVisibleItemPosition 之类的方法，但是它们没有告诉第一个可见项是否实际上是列表中的第一项.

I am aware about the methods like findFirstVisibleItemPosition and findLastVisibleItemPosition but they did not tell whether the first visible item is actually the first item of the list or not.

我要解决的问题是，我有一个视图寻呼机作为回收器视图的第一项，当用户向下滚动并变得完全不可见时，我想停止自动滚动.

The problem that I am trying to solve is this, I have a view pager as the first item of my recycler view and I want to stop auto scroll when user scrolls down and it becomes completely invisible.

如果有人对如何执行此操作有任何想法，请提供帮助.

Please help if anyone has any idea about how to do this.

推荐答案

您可以通过检查

You can do it by checking if findFirstVisibleItemPosition is 0 or not, like this :

// layoutManager is your recycler view's layout manager
int position = layoutManager.findFirstVisibleItemPosition();
if(position != 0){
    stopAutoScroll();
}else{
    startAutoScroll();
}

即，如果 findFirstVisibleItemPosition 返回 0 ，我们应该开始自动滚动；如果不是 0 ，则停止滑动.

i.e, if findFirstVisibleItemPosition returns 0 we should start auto scroll and if it is not 0, stop swiping.

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