android - 如何使用同一个适配器在回收站 View 上显示多个模型？

Question

我有两种不同类型的对象(例如:用户和学生)，它们都具有不同的属性。

用户:标题、描述；
学生:标题、描述、USN；

有没有一种方法可以使用相同的适配器在回收站 View 中先显示两个用户，然后再显示学生？即使它是两个适配器，我如何显示它。我不想要两个回收站 View 。

请注意，给出的示例非常简单。更改不仅在 UI 中。如果更改仅在 UI 中，则可以使用 getItemViewType()，但此处更改在模型本身中。

List<Student>和 List<User>

我们如何将两个列表设置为相同的适配器？

Answer 1

您必须使用覆盖方法“getItemViewType(position)”。

然后像这样根据 ViewType 返回 ViewHolder，

  @Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    RecyclerView.ViewHolder viewHolder = null;
    LayoutInflater inflater = LayoutInflater.from(parent.getContext());

    switch (viewType) {
        case ITEM:
            View v1 = inflater.inflate(R.layout.item_student, parent, false);
            viewHolder = new UserVH(v1);
            break;
        case LOADING:
            View v2 = inflater.inflate(R.layout.item_user, parent, false);
            viewHolder = new StudentVH(v2);
            break;
    }
    return viewHolder;
}

编辑:

 public class StudentVH extends RecyclerView.ViewHolder {
    //Declare student views

    public ViewHolder(View v) {
        super(v);
        //Inialize student views
    }
}

 public class UserVH extends RecyclerView.ViewHolder {
    //Declare user views

    public ViewHolder(View v) {
        super(v);
        //Inialize user views
    }
}

第二次编辑:

你的 Adapter 应该是这样的，

public class ClGAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Context context;
private List<UserBean> userBeans;
private List<StudentBean> studentBeans;
private UserBean userBeanItem;
private StudentBean studentBeanItem;
private int size = 0;


public ClGAdapter(Context context, List<UserBean> userBeans, List<StudentBean> studentBeans) {
    this.context = context;
    this.userBeans = userBeans;
    this.studentBeans = studentBeans;
    this.size = userBeans.size() + studentBeans.size();
}


@Override
public int getItemViewType(int position) {

    if (position > (userBeans.size() - 1)) {
        return 2;//TYPE_STUDENT
    } else {
        return 1; //TYPE_USER
    }
}

@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {

    int viewType = holder.getItemViewType();

    userBeanItem = userBeans.get(position);
    studentBeanItem = studentBeans.get(position);
    switch (viewType) {
        case 1:
            ((UserHolder) holder).mUserName.setText(userBeanItem.getUserName());
            break;
        case 2:
            ((StudentHolder) holder).mStudentName.setText(studentBeanItem.getStudentName());
            break;
        default:
            break;
    }

}

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

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    int layout = 0;
    RecyclerView.ViewHolder viewHolder;
    switch (viewType) {
        case 1: 
            layout = R.layout.user_card;
            View userView = LayoutInflater.from(parent.getContext()).inflate(layout, parent, false);
            viewHolder = new UserHolder(userView);
            break;
        case 2:
            layout = R.layout.student_card;
            View studentView = LayoutInflater.from(parent.getContext()).inflate(layout, parent, false);
            viewHolder = new StudentHolder(studentView);

            break;
        default:
            viewHolder = null;
            break;
    }
    return viewHolder;
}

public class UserHolder extends RecyclerView.ViewHolder {
    private TextView mUserName;

    public UserHolder(View v) {
        super(v);
        mUserName = v.findViewById(R.id.user_name);
    }
}

public class StudentHolder extends RecyclerView.ViewHolder {
    private TextView mStudentName;

    public StudentHolder(View v) {
        super(v);
        mStudentName = v.findViewById(R.id.student_name);
    }
}
}