如果你使用Header和GridLayoutManager，使用以下代码在Kotlin中编写的网格间距:

inner class SpacesItemDecoration(itemSpace: Int) : RecyclerView.ItemDecoration() {

    var space: Int = itemSpace

    override fun getItemOffsets(outRect: Rect?, view: View?, parent: RecyclerView?, state: RecyclerView.State?) {
        super.getItemOffsets(outRect, view, parent, state)
        val position = parent!!.getChildAdapterPosition(view)
        val viewType = parent.adapter.getItemViewType(position)
        
        // Check to not to set any margin to header item 
        if (viewType == GridViewAdapter.TYPE_HEADER) {
            outRect!!.top = 0
            outRect.left = 0
            outRect.right = 0
            outRect.bottom = 0
        } else {
            outRect!!.left = space
            outRect.right = space
            outRect.bottom = space

            if (parent.getChildLayoutPosition(view) == 0) {
                outRect.top = space
            } else {
                outRect.top = 0
            }
        }
    }
}

并将ItemDecoration传递给RecyclerView为:

gridView.addItemDecoration(SpacesItemDecoration(10))

这个问题的答案似乎比他们应该做的要复杂。以下是我的看法。

假设您希望网格项之间有1dp的间距。做以下几点:

为每个项目添加0.5dp的填充 给RecycleView添加-0.5dp的填充 就是这样!：）

对我来说，完美的解决方案是设置RecyclerView的宽度它的layoutmanager为GridLayoutManager为wrap_content

试试这个。它会照顾到周围的等距。适用于列表，网格和StaggeredGrid。

编辑

更新后的代码应该可以处理大多数带有跨度、方向等的角落情况。 注意，如果在GridLayoutManager中使用setSpanSizeLookup()，出于性能考虑，建议设置setSpanIndexCacheEnabled()。

注意，似乎与StaggeredGrid，似乎有一个错误的索引的孩子变得古怪和难以跟踪，所以下面的代码可能不会很好地与StaggeredGridLayoutManager。

public class ListSpacingDecoration extends RecyclerView.ItemDecoration {

  private static final int VERTICAL = OrientationHelper.VERTICAL;

  private int orientation = -1;
  private int spanCount = -1;
  private int spacing;
  private int halfSpacing;


  public ListSpacingDecoration(Context context, @DimenRes int spacingDimen) {

    spacing = context.getResources().getDimensionPixelSize(spacingDimen);
    halfSpacing = spacing / 2;
  }

  public ListSpacingDecoration(int spacingPx) {

    spacing = spacingPx;
    halfSpacing = spacing / 2;
  }

  @Override
  public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {

    super.getItemOffsets(outRect, view, parent, state);

    if (orientation == -1) {
        orientation = getOrientation(parent);
    }

    if (spanCount == -1) {
        spanCount = getTotalSpan(parent);
    }

    int childCount = parent.getLayoutManager().getItemCount();
    int childIndex = parent.getChildAdapterPosition(view);

    int itemSpanSize = getItemSpanSize(parent, childIndex);
    int spanIndex = getItemSpanIndex(parent, childIndex);

    /* INVALID SPAN */
    if (spanCount < 1) return;

    setSpacings(outRect, parent, childCount, childIndex, itemSpanSize, spanIndex);
  }

  protected void setSpacings(Rect outRect, RecyclerView parent, int childCount, int childIndex, int itemSpanSize, int spanIndex) {

    outRect.top = halfSpacing;
    outRect.bottom = halfSpacing;
    outRect.left = halfSpacing;
    outRect.right = halfSpacing;

    if (isTopEdge(parent, childCount, childIndex, itemSpanSize, spanIndex)) {
        outRect.top = spacing;
    }

    if (isLeftEdge(parent, childCount, childIndex, itemSpanSize, spanIndex)) {
        outRect.left = spacing;
    }

    if (isRightEdge(parent, childCount, childIndex, itemSpanSize, spanIndex)) {
        outRect.right = spacing;
    }

    if (isBottomEdge(parent, childCount, childIndex, itemSpanSize, spanIndex)) {
        outRect.bottom = spacing;
    }
  }

  @SuppressWarnings("all")
  protected int getTotalSpan(RecyclerView parent) {

    RecyclerView.LayoutManager mgr = parent.getLayoutManager();
    if (mgr instanceof GridLayoutManager) {
        return ((GridLayoutManager) mgr).getSpanCount();
    } else if (mgr instanceof StaggeredGridLayoutManager) {
        return ((StaggeredGridLayoutManager) mgr).getSpanCount();
    } else if (mgr instanceof LinearLayoutManager) {
        return 1;
    }

    return -1;
  }

  @SuppressWarnings("all")
  protected int getItemSpanSize(RecyclerView parent, int childIndex) {

    RecyclerView.LayoutManager mgr = parent.getLayoutManager();
    if (mgr instanceof GridLayoutManager) {
        return ((GridLayoutManager) mgr).getSpanSizeLookup().getSpanSize(childIndex);
    } else if (mgr instanceof StaggeredGridLayoutManager) {
        return 1;
    } else if (mgr instanceof LinearLayoutManager) {
        return 1;
    }

    return -1;
  }

  @SuppressWarnings("all")
  protected int getItemSpanIndex(RecyclerView parent, int childIndex) {

    RecyclerView.LayoutManager mgr = parent.getLayoutManager();
    if (mgr instanceof GridLayoutManager) {
        return ((GridLayoutManager) mgr).getSpanSizeLookup().getSpanIndex(childIndex, spanCount);
    } else if (mgr instanceof StaggeredGridLayoutManager) {
        return childIndex % spanCount;
    } else if (mgr instanceof LinearLayoutManager) {
        return 0;
    }

    return -1;
  }

  @SuppressWarnings("all")
  protected int getOrientation(RecyclerView parent) {

    RecyclerView.LayoutManager mgr = parent.getLayoutManager();
    if (mgr instanceof LinearLayoutManager) {
        return ((LinearLayoutManager) mgr).getOrientation();
    } else if (mgr instanceof GridLayoutManager) {
        return ((GridLayoutManager) mgr).getOrientation();
    } else if (mgr instanceof StaggeredGridLayoutManager) {
        return ((StaggeredGridLayoutManager) mgr).getOrientation();
    }

    return VERTICAL;
  }

  protected boolean isLeftEdge(RecyclerView parent, int childCount, int childIndex, int itemSpanSize, int spanIndex) {

    if (orientation == VERTICAL) {

        return spanIndex == 0;

    } else {

        return (childIndex == 0) || isFirstItemEdgeValid((childIndex < spanCount), parent, childIndex);
    }
  }

  protected boolean isRightEdge(RecyclerView parent, int childCount, int childIndex, int itemSpanSize, int spanIndex) {

    if (orientation == VERTICAL) {

        return (spanIndex + itemSpanSize) == spanCount;

    } else {

        return isLastItemEdgeValid((childIndex >= childCount - spanCount), parent, childCount, childIndex, spanIndex);
    }
  }

  protected boolean isTopEdge(RecyclerView parent, int childCount, int childIndex, int itemSpanSize, int spanIndex) {

    if (orientation == VERTICAL) {

        return (childIndex == 0) || isFirstItemEdgeValid((childIndex < spanCount), parent, childIndex);

    } else {

        return spanIndex == 0;
    }
  }

  protected boolean isBottomEdge(RecyclerView parent, int childCount, int childIndex, int itemSpanSize, int spanIndex) {

    if (orientation == VERTICAL) {

        return isLastItemEdgeValid((childIndex >= childCount - spanCount), parent, childCount, childIndex, spanIndex);

    } else {

        return (spanIndex + itemSpanSize) == spanCount;
    }
  }

  protected boolean isFirstItemEdgeValid(boolean isOneOfFirstItems, RecyclerView parent, int childIndex) {

    int totalSpanArea = 0;
    if (isOneOfFirstItems) {
        for (int i = childIndex; i >= 0; i--) {
            totalSpanArea = totalSpanArea + getItemSpanSize(parent, i);
        }
    }

    return isOneOfFirstItems && totalSpanArea <= spanCount;
  }

  protected boolean isLastItemEdgeValid(boolean isOneOfLastItems, RecyclerView parent, int childCount, int childIndex, int spanIndex) {

    int totalSpanRemaining = 0;
    if (isOneOfLastItems) {
        for (int i = childIndex; i < childCount; i++) {
            totalSpanRemaining = totalSpanRemaining + getItemSpanSize(parent, i);
        }
    }

    return isOneOfLastItems && (totalSpanRemaining <= spanCount - spanIndex);
  }
}

希望能有所帮助。

只有一个简单的解决方案，您可以记住并在任何需要的地方实施。没有bug，没有疯狂的计算。在卡片/物品布局中放置空白，并在RecyclerView中放置相同大小的填充:

item_layout.xml

<CardView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:margin="10dp">

activity_layout.xml

<RecyclerView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="10dp"/>

更新:

如果你有一个在列表和网格之间切换的拨动开关，不要忘记在设置任何新的项目装饰之前调用recyclerView.removeItemDecoration(..)。如果不是这样，那么新的间隔计算将是不正确的。

就像这样:

recyclerView.removeItemDecoration(gridItemDecorator)
recyclerView.removeItemDecoration(listItemDecorator)

if (showAsList) {
    recyclerView.layoutManager = LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false)
    recyclerView.addItemDecoration(listItemDecorator)
} else {
    recyclerView.layoutManager = GridLayoutManager(this, spanCount)
    recyclerView.addItemDecoration(gridItemDecorator)
}