recyclerview 中的最后一项被切断

在使用 RecyclerView 进行列表展示时，我们经常会遇到一个问题，即最后一项被切断的情况。这种情况一般发生在列表的最后一项高度超过了屏幕剩余空间，导致最后一项只显示了部分内容，而剩下的部分被切断了。这样的情况对用户来说，可能会造成一种不完整的视觉体验，因此我们需要找到一种解决方案来避免这种情况的发生。

xml
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="200dp"
    />

java
public class LastItemDecoration extends RecyclerView.ItemDecoration {
  
    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        
        int position = parent.getChildAdapterPosition(view);
        int itemCount = parent.getAdapter().getItemCount();
        
        if (position == itemCount - 1) {
            outRect.set(0, 0, 0, 200); // 设置最后一项的底部偏移量为 200px
        }
    }
}

java
LastItemDecoration itemDecoration = new LastItemDecoration();
recyclerView.addItemDecoration(itemDecoration);

java
public class LastLayoutManager extends LinearLayoutManager {
  
    public LastLayoutManager(Context context) {
        super(context);
    }
  
    @Override
    public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
        super.onLayoutChildren(recycler, state);
        
        int lastVisibleItemPosition = findLastVisibleItemPosition();
        int itemCount = getItemCount();
        
        if (lastVisibleItemPosition == itemCount - 1) {
            View lastItemView = getChildAt(lastVisibleItemPosition);
            int bottomOffset = getHeight() - getPaddingBottom() - getDecoratedBottom(lastItemView);
            
            if (bottomOffset > 0) {
                offsetChildrenVertical(-bottomOffset);
            }
        }
    }
}

java
LastLayoutManager layoutManager = new LastLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);