java - Recyclerview 布局管理器在 Android 中滚动后获取位置 View

Question

Recyclerview正在滚动它的 LinearLayoutManager像这样lm.scrollToPositionWithOffset(position, offset) .如何在滚动前获取滚动位置的 View ？滚动后将滚动返回 null 的 View ，因为仍未创建。我试过 Runnable , Observer和 onLayoutCompleted但仍然为空。如何获得 View ？

lm.scrollToPositionWithOffset(position, offset);

recyclerView.post(new Runnable(){
    @Override
    public void run(){
        View v1 = recyclerView.getChildAt(position); // returning null.
        View v2 = recyclerView.getLayoutManager().getChildAt(position); // returning null.
    }
});

recyclerView.getViewTreeObserver()
   .addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
       @Override
       public void onGlobalLayout() {
           View v1 = recyclerView.getChildAt(position); // returning null.
           View v2 = recyclerView.getLayoutManager().getChildAt(position); // returning null.
       recyclerView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}});

@Override // in LinearLayoutManager
public void onLayoutCompleted(RecyclerView.State state) {
    super.onLayoutCompleted(state);
    View v1 = recyclerView.getChildAt(position); // returning null.
    View v2 = this.getChildAt(position); // returning null.  
}

Answer 1

View v = lm.getChildAt(position);
lm.scrollToPositionWithOffset(position, offset);
v.post(new Runnable() {
    @Override
    public void run() {
        // View is ready here.                
});