android StaggeredGridLayoutManager中的项目重叠

Question

recyclerviews中的项目重叠：

这是recyclerview声明：

recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
arrayList = new ArrayList<>();
arrayList.add(new DataModel2x2("Item 1", R.drawable.battle, "#09A9FF"));
arrayList.add(new DataModel4x4("Item 2", R.drawable.beer, "#3E51B1"));
arrayList.add(new DataModel4x2("Item 3", R.drawable.ferrari, "#673BB7"));
arrayList.add(new DataModel4x2("Item 4", R.drawable.jetpack_joyride,   
 "#4BAA50"));
arrayList.add(new DataModel4x4("Item 5", R.drawable.three_d, "#F94336"));
arrayList.add(new DataModel2x4("Item 6", R.drawable.battle, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 7", R.drawable.beer, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 8", R.drawable.ferrari, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 9", R.drawable.jetpack_joyride, 
"#0A9B88"));
arrayList.add(new DataModel2x2("Item 10", R.drawable.three_d, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 12", R.drawable.battle, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 13", R.drawable.beer, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 14", R.drawable.ferrari, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 15", R.drawable.jetpack_joyride, 
"#0A9B88"));
arrayList.add(new DataModel2x2("Item 16", R.drawable.three_d, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 17", R.drawable.battle, "#0A9B88"));
arrayList.add(new DataModel2x2("Item 18", R.drawable.ferrari, "#0A9B88"));

RecyclerViewAdapter adapter = new RecyclerViewAdapter(this, arrayList, 
this);
recyclerView.setAdapter(adapter);

StaggeredGridLayoutManager manager = new StaggeredGridLayoutManager( 2,   
GridLayoutManager.HORIZONTAL);

recyclerView.setLayoutManager(manager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.addItemDecoration(new ItemOffsetDecoration(20));

这是适配器：

package com.journaldev.recyclerviewgridlayoutmanager;

import android.content.Context;
import android.graphics.Color;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
 import android.widget.RelativeLayout;
 import android.widget.TextView;

 import java.util.ArrayList;

  public class RecyclerViewAdapter extends    
  RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> {

  ArrayList<Tileable> mValues;
 Context mContext;
protected ItemListener mListener;

 public RecyclerViewAdapter(Context context, ArrayList<Tileable> values, 
 ItemListener itemListener) {

    mValues = values;
    mContext = context;
    mListener = itemListener;
}

@Override
public int getItemViewType(int position) {
    if (Tileable.TILE2x2 == mValues.get(position).getTileType()) {
        return Tileable.TILE2x2;
    } else if (Tileable.TILE2x4 == mValues.get(position).getTileType()) {
        return Tileable.TILE2x4;
    } else if (Tileable.TILE4x2 == mValues.get(position).getTileType()) {
        return Tileable.TILE4x2;
    }

    return Tileable.TILE4x4;
}

public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    public TextView textView;
    public TextView textViewDescription;
    public ImageView imageView;
    public RelativeLayout relativeLayout;
    Tileable item;

    public ViewHolder(View v) {
        super(v);

        v.setOnClickListener(this);
        textView = (TextView) v.findViewById(R.id.textView);
        imageView = (ImageView) v.findViewById(R.id.imageView);
        relativeLayout = (RelativeLayout) v.findViewById(R.id.relativeLayout);
        textViewDescription = (TextView) v.findViewById(R.id.textViewDescription);

    }

    public void setData(Tileable item) {
        this.item = item;

        textView.setText(item.getText());
        imageView.setImageResource(item.getDrawable());
        relativeLayout.setBackgroundColor(Color.parseColor(item.getColor()));
        switch (item.getTileType()) {
            case Tileable.TILE2x2 :{
                textViewDescription.setText("2x2 TILE");
                break;
            }

            case Tileable.TILE2x4 :{
                textViewDescription.setText("2x4 TILE");
                break;
            }

            case Tileable.TILE4x2 :{
                textViewDescription.setText("4x2 TILE");
                break;
            }

            case Tileable.TILE4x4 :{
                textViewDescription.setText("4x4 TILE");
                break;
            }
        }
    }


    @Override
    public void onClick(View view) {
        if (mListener != null) {
            mListener.onItemClick(item);
        }
    }
}

@Override
public RecyclerViewAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View view = null;
    if (viewType == Tileable.TILE2x2) {
        view = LayoutInflater.from(mContext).inflate(R.layout.recycler_view_item, parent, false);
    } else if (viewType == Tileable.TILE2x4) {
        view = LayoutInflater.from(mContext).inflate(R.layout.recycler_view_item_2x4, parent, false);
    } else if (viewType == Tileable.TILE4x2) {
        view = LayoutInflater.from(mContext).inflate(R.layout.recycler_view_item_4x2, parent, false);
    } else if (viewType == Tileable.TILE4x4) {
        view = LayoutInflater.from(mContext).inflate(R.layout.recycler_view_item_4x4, parent, false);
    }

    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(ViewHolder Vholder, int position) {
    Vholder.setData(mValues.get(position));
}

@Override
public int getItemCount() {
    return mValues.size();
}

public interface ItemListener {
    void onItemClick(Tileable item);
}
}

我附上布局失败的图片：   

当我仅添加2x2和2x4磁贴时，布局很好。但是当我添加4x4或4x2项时，交错网格布局中的recyclerView项变得重叠了