Question

我试图在我的适配器中使用两种类型的视图和两种类型的ViewHolders，但是我看到以下错误：

java.lang.ClassCastException: com.Sleep.Adapters.FriendsListAdapterFromKesh$ViewHolder2 cannot be cast to com.Sleep.Adapters.FriendsListAdapterFromKesh$ViewHolder1
        at com.Sleep.Adapters.FriendsListAdapterFromKesh.getView(FriendsListAdapterFromKesh.java:226)
        at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
        at android.widget.AbsListView.obtainView(AbsListView.java:2186)
        at android.widget.ListView.makeAndAddView(ListView.java:1845)
        at android.widget.ListView.fillUp(ListView.java:712)
        at android.widget.ListView.fillGap(ListView.java:651)

以下是完整的适配器类：

public class FriendsListAdapterFromKesh extends ArrayAdapter<FriendListEntryItem> {
List<FriendListEntryItem> friends;
List<FriendListEntryItem> friendsWithoutPoints;
Context context;
private LayoutInflater inflater;
private LayoutInflater mLayoutInflater;
private int type;
private static String ROOT_DIRECTORY_PATH = Environment.getExternalStorageDirectory() + File.separator + ".Sleep/Photos old";
FriendsTab friendsTab;

public FriendsListAdapterFromKesh(Context context, final List<FriendListEntryItem> friends, final List<FriendListEntryItem> friendsWithoutPoints) {
    super(context, 0);
    this.context = context;
    inflater = LayoutInflater.from(context);
    this.friendsWithoutPoints = friendsWithoutPoints;
    this.friends = friends;
    friendsTab = new FriendsTab();
    mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

public int getCountFriendsWithPoints() {
    return friends.size();
}


public List<FriendListEntryItem> getFriends() {
    return friends;
}


public List<FriendListEntryItem> getFriendsWithoutPoints() {
    return friendsWithoutPoints;
}

@Override
public int getCount() {
        return friends.size() + friendsWithoutPoints.size();
}

    FriendListEntryItem ei = friends.get(position - step);
    return ei.userId + "," + ei.socType + "," + ei.name;
}

static class ViewHolder1 {
    public ImageView image;
    public TextView title;
    public TextView subtitle;
}

static class ViewHolder2 {
    public ImageView image;
    public TextView title;
    public TypefacedButton button;
}

@Override
public int getItemViewType(int pos) {
    if (pos < friends.size())
        return 1;
    return 2;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    int viewType = getItemViewType(position);

    if (convertView == null) {
        if (viewType == 1) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.list_frnds_item_with_points, parent, false);
            ViewHolder1 viewHolder1 = new ViewHolder1();
            viewHolder1.title = (TextView) convertView.findViewById(R.id.list_item_title_friend);
            viewHolder1.image = (ImageView) convertView.findViewById(R.id.imageFriendAva);
            viewHolder1.subtitle = (TextView) convertView.findViewById(R.id.list_item_friend_woke_time);
            convertView.setTag(viewHolder1);
        } else {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.list_frnds_item_without_points, parent, false);

            ViewHolder2 viewHolder2 = new ViewHolder2();
            viewHolder2.title = (TextView) convertView.findViewById(R.id.list_item_title_friend);
            viewHolder2.image = (ImageView) convertView.findViewById(R.id.imageFriendAva);
            viewHolder2.subtitle = (TextView) convertView.findViewById(R.id.list_item_friend_woke_time);
            convertView.setTag(viewHolder2);
        }

    } else {
        if (convertView.getTag().getClass().equals(ViewHolder1.class)) {
            ViewHolder1 holder1 = (ViewHolder1) convertView.getTag();
            final FriendListEntryItem ei = friends.get(position);
            if (ei != null) {
                if (holder1.title != null) {
                    holder1.title.setText(ei.name);
                }
                if (holder1.button != null) {
                    holder1.button.setFriendItem(ei);
                }
                if (holder1.image != null) {
                    File picture = findPicture(ei.name);
                    if (picture != null && picture.exists()) {
                        Picasso.with(context).load("file://" + picture.getAbsolutePath()).fit().centerCrop().into(holder1.image);
                    }
                }
            }
        } if (convertView.getTag().getClass().equals(ViewHolder2.class)) {
            ViewHolder2 holder2 = (ViewHolder2) convertView.getTag();
            final FriendListEntryItem ei = friendsWithoutPoints.get(position - friends.size());
            if (ei != null) {
                if (holder2.title != null) {
                    holder2.title.setText(ei.name);
                }
                if (holder2.button != null) {
                    holder2.button.setFriendItem(ei);
                }
                if (holder2.image != null) {
                    File picture = findPicture(ei.name);
                    if (picture != null && picture.exists()) {
                        Picasso.with(context).load("file://" + picture.getAbsolutePath()).fit().centerCrop().into(holder2.image);
                    }
                }
            }
        }
    }
    return convertView;
}

Answer 1

您没有覆盖getViewTypeCount。你需要添加

@Override
public int getViewTypeCount() {
    return 2;
}

FriendsListAdapterFromKesh类中的

，以便您的自定义适配器知道预期有多少种不同的视图。由于您没有覆盖getViewTypeCount，您的适配器甚至可能无法检查getItemViewType返回的值，它只是使所有视图都相同（第一个）类型。

使用具有两种视图类型的适配器时ClassCastException

1 个答案: