/**
* 滑动到指定位置
*
* @param mRecyclerView
* @param position
*/
private void smoothMoveToPosition(RecyclerView mRecyclerView, final int position) {
// 第一个可见位置
int firstItem = mRecyclerView.getChildLayoutPosition(mRecyclerView.getChildAt(0));
// 最后一个可见位置
int lastItem = mRecyclerView.getChildLayoutPosition(mRecyclerView.getChildAt(mRecyclerView.getChildCount() - 1));
if (position < firstItem) {
// 如果跳转位置在第一个可见位置之前,就smoothScrollToPosition可以直接跳转
mRecyclerView.smoothScrollToPosition(position);
} else if (position <= lastItem) {
// 跳转位置在第一个可见项之后,最后一个可见项之前
// smoothScrollToPosition根本不会动,此时调用smoothScrollBy来滑动到指定位置
int movePosition = position - firstItem;
if (movePosition >= 0 && movePosition < mRecyclerView.getChildCount()) {
int top = mRecyclerView.getChildAt(movePosition).getTop();
mRecyclerView.smoothScrollBy(0, top);
}
} else {
// 如果要跳转的位置在最后可见项之后,则先调用smoothScrollToPosition将要跳转的位置滚动到可见位置
// 再通过onScrollStateChanged控制再次调用smoothMoveToPosition,执行上一个判断中的方法
mRecyclerView.smoothScrollToPosition(position);
mToPosition = position;
mShouldScroll = true;
}
}
监听
binding.recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (mShouldScroll) {
mShouldScroll = false;
smoothMoveToPosition(binding.recyclerView, mToPosition);
}
}
});
再使用即可
smoothMoveToPosition(binding.recyclerView, mToPosition);
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