如何在适配器中扩展多个类？

Question

我想在列表中实现部分。我有一份任务清单。 List有一个自定义适配器，它扩展了recyclerview刷卡适配器，因为我已经实现了向recyclerview的滑动手势。

因此，现在任务列表与已完成和待处理任务一起显示。每个列表项都有一个复选框，显示任务已完成或待处理。

如果选中复选框，则任务完成，反之亦然。现在我想用标题创建两个部分。一个用于已完成的任务，另一个用于待处理任

所以完成的任务应该显示在已完成的部分内，反之亦然。此外，如果未检查任务，即挂起，如果用户选中复选框，则该项应从待处理部分中删除，并应添加到已完成的部分，反之亦然。

我检查了一个库的部分。

https://github.com/afollestad/sectioned-recyclerview

但是当我尝试实现库时，我得到了错误，即适配器无法扩展两个类，因为之前我已经扩展了recyclerview swipe库。

扩展sectionedRecyclerview适配器后的onBindViewHolder方法我得到错误，因为IAdapter应该实现onBindViewHolder（VH，int）

怎么解决这个？

适配器：

    public class IAdapter extends RecyclerSwipeAdapter<IAdapter.ItemViewHolder> , SectionedRecyclerViewAdapter<IAdapter.ItemViewHolder> {

    public ArrayList<Task> items;
    Context conext;
    public int _mId;

    List<Task> itemsPendingRemoval = new ArrayList<>();

    public IAdapter(Context context, ArrayList<Task> item) {
        this.conext=context;
       this.items=item;
    }

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

    @Override
    public int getItemCount(int section) {
        return items.size();

    }

    public static class ItemViewHolder extends RecyclerView.ViewHolder {
        Task task;
        CheckBox cb;
        SwipeLayout swipeLayout;
        TaskTableHelper taskTableHelper;
        ItemViewHolder(final View itemView) {
            super(itemView);

            taskTableHelper= new TaskTableHelper(itemView.getContext());
            swipeLayout = (SwipeLayout) itemView.findViewById(R.id.swipe);
            cb = (CheckBox) itemView.findViewById(R.id.checkbox);

        }
    }

    @Override
    public void onBindViewHolder(final ItemViewHolder itemViewHolder, int section,final int i, int absolutePosition) {

        itemViewHolder.cb.setText(items.get(i).getTitle());

        itemViewHolder.task = items.get(i);

        int taskId = itemViewHolder.task.getId();

        itemViewHolder.task = itemViewHolder.taskTableHelper.getTask(taskId);

        int status = itemViewHolder.task.getStatus();

        if(status == 0)
        {
            itemViewHolder.cb.setTextColor(Color.WHITE);
        }

        else {

            itemViewHolder.cb.setChecked(true);

            itemViewHolder.cb.setTextColor(Color.parseColor("#B0BEC5"));

        }


       itemViewHolder.cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

                if (isChecked) {

                    itemViewHolder.cb.setTextColor(Color.parseColor("#B0BEC5"));

                    itemViewHolder.task.setStatus(1);

                    itemViewHolder.taskTableHelper.updateStatus(itemViewHolder.task);

                }
                else

                {

                    itemViewHolder.cb.setTextColor(Color.WHITE);

                    itemViewHolder.task.setStatus(0);

                    itemViewHolder.taskTableHelper.updateStatus(itemViewHolder.task);

                }

            }

        });



        final Task item = items.get(i);
        itemViewHolder.swipeLayout.addDrag(SwipeLayout.DragEdge.Right,itemViewHolder.swipeLayout.findViewById(R.id.bottom_wrapper_2));
        itemViewHolder.swipeLayout.setShowMode(SwipeLayout.ShowMode.LayDown);

        itemViewHolder.swipeLayout.setOnDoubleClickListener(new SwipeLayout.DoubleClickListener() {
            @Override
            public void onDoubleClick(SwipeLayout layout, boolean surface) {
                Toast.makeText(conext, "DoubleClick", Toast.LENGTH_SHORT).show();
            }
        });
        itemViewHolder.swipeLayout.findViewById(R.id.trash2).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mItemManger.removeShownLayouts(itemViewHolder.swipeLayout);
                items.remove(i);
                notifyItemRemoved(i);
                notifyItemRangeChanged(i, items.size());
                mItemManger.closeAllItems();

                itemViewHolder.taskTableHelper.deleteTask(item);

                _mId = item.getAlertId();

                cancelNotification();

                Toast.makeText(view.getContext(), "Deleted " + itemViewHolder.cb.getText().toString() + "!", Toast.LENGTH_SHORT).show();
            }
        });

        itemViewHolder.swipeLayout.findViewById(R.id.done).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                itemViewHolder.task.setStatus(1);
                itemViewHolder.taskTableHelper.updateStatus(itemViewHolder.task);
                itemViewHolder.cb.setChecked(true);
                Toast.makeText(conext, "Task Completed.", Toast.LENGTH_SHORT).show();
            }
        });

        itemViewHolder.swipeLayout.getSurfaceView().setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                boolean mEditMode;

                int id = item.getId();
                int priority = item.getTaskPriority();
                String title = item.getTitle();
                String alertDate = item.getAlertDate();
                String alertTime = item.getAlertTime();
                String dueDate = item.getDueDate();
                String dueTime = item.getDueTime();
                _mId = item.getAlertId();

                int listId = item.getList();

                mEditMode = true;

                Intent i = new Intent(conext, AddTaskActivity.class);

                i.putExtra("taskId", id);
                i.putExtra("taskTitle", title);
                i.putExtra("taskPriority", priority);
                i.putExtra("taskAlertTime", alertTime);
                i.putExtra("taskAlertDate", alertDate);
                i.putExtra("taskDueDate", dueDate);
                i.putExtra("taskDueTime", dueTime);
                i.putExtra("taskListId", listId);
                i.putExtra("EditMode", mEditMode);
                i.putExtra("AlertId",_mId);

                conext.startActivity(i);

            }
        });


        mItemManger.bindView(itemViewHolder.itemView, i);

    }

    @Override
    public ItemViewHolder onCreateViewHolder(ViewGroup viewGroup,int position) {

            View itemView = LayoutInflater.
                    from(viewGroup.getContext()).
                    inflate(R.layout.card_layout, viewGroup, false);
            return new ItemViewHolder(itemView);

    }



        @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }


    public void remove(int position) {
       Task item = items.get(position);
        if (itemsPendingRemoval.contains(item)) {
            itemsPendingRemoval.remove(item);
        }
        if (items.contains(item)) {
            items.remove(position);
            notifyItemRemoved(position);
        }
    }

    public void cancelNotification()
    {
        AlarmManager alarmManager = (AlarmManager)conext.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent(conext, NotificationReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(conext,_mId, intent, 0);
        alarmManager.cancel(pendingIntent);
    }
    @Override
    public int getSwipeLayoutResourceId(int position) {
        return R.id.swipe;
    }
}

请帮忙..谢谢..

Answer 1

您可以使用库SectionedRecyclerViewAdapter轻松实现此目的。

首先创建一个Section类来分组您的任务：

class TaskSection extends StatelessSection {

    String title;
    List<Task> list;

    public TaskSection(String title, List<Task> list) {
        // call constructor with layout resources for this Section header, footer and items 
        super(R.layout.section_header, R.layout.section_item);

        this.title = title;
        this.list = list;
    }

    @Override
    public int getContentItemsTotal() {
        return list.size(); // number of items of this section
    }

    public int addTask(Task task) {
        return list.add(task;
    }

    public int removeTask(Task task) {
        return list.remove(task;
    }

    @Override
    public RecyclerView.ViewHolder getItemViewHolder(View view) {
        // return a custom instance of ViewHolder for the items of this section
        return new MyItemViewHolder(view);
    }

    @Override
    public void onBindItemViewHolder(RecyclerView.ViewHolder holder, int position) {
        MyItemViewHolder itemHolder = (MyItemViewHolder) holder;

        // bind your view here
        itemHolder.tvItem.setText(list.get(position).getTitle());
    }

    @Override
    public RecyclerView.ViewHolder getHeaderViewHolder(View view) {
        return new SimpleHeaderViewHolder(view);
    }

    @Override
    public void onBindHeaderViewHolder(RecyclerView.ViewHolder holder) {
        MyHeaderViewHolder headerHolder = (MyHeaderViewHolder) holder;

        // bind your header view here
        headerHolder.tvItem.setText(title);
    }
}

然后使用您的章节设置RecyclerView：

// Create an instance of SectionedRecyclerViewAdapter 
SectionedRecyclerViewAdapter sectionAdapter = new SectionedRecyclerViewAdapter();

// Create your sections with the list of data
TaskSection compSection = new TaskSection("Completed", compList);
TaskSection pendSection = new TaskSection("Pending", pendList);

// Add your Sections to the adapter
sectionAdapter.addSection(compSection);
sectionAdapter.addSection(pendSection);

// Set up your RecyclerView with the SectionedRecyclerViewAdapter
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
recyclerView.setAdapter(sectionAdapter);

现在，如果您要将任务从“待处理”部分发送到“已完成”：

pendSection.removeTask(task);
compSection.addTask(task);
sectionAdapter.notifyDataSetChanged();

Answer 2

此示例还发布了您发布的链接。你可以像这样实现。

public class MainAdapter extends SectionedRecyclerViewAdapter<MainAdapter.MainVH> {

        @Override
        public int getSectionCount() {
            return 20; // number of sections.
        }

        @Override
        public int getItemCount(int section) {
            return 8; // number of items in section (section index is parameter).
        }

        @Override
        public void onBindHeaderViewHolder(MainVH holder, int section) {
            // Setup header view.
        }

        @Override
        public void onBindViewHolder(MainVH holder, int section, int relativePosition, int absolutePosition) {
            // Setup non-header view.
            // 'section' is section index.
            // 'relativePosition' is index in this section.
            // 'absolutePosition' is index out of all non-header items.
            // See sample project for a visual of how these indices work.
        }

        @Override
        public MainVH onCreateViewHolder(ViewGroup parent, int viewType) {
            // Change inflated layout based on 'header'. 
            View v = LayoutInflater.from(parent.getContext())
                    .inflate(viewType == VIEW_TYPE_HEADER ? R.layout.header : R.layout.normal, parent, false);
            return new MainVH(v);
        }

        public static class MainVH extends RecyclerView.ViewHolder {

            public MainVH(View itemView) {
                super(itemView);
                // Setup view holder.
                // You'd want some views to be optional, e.g. for header vs. normal.
            }
        }
    }

Answer 3

将Recyclerview拆分为多个部分的最简单方法是使用带有标题和项目的布局，然后更改标题的可见性是相同的。

布局：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/tvHeader"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="start"
        android:padding="16dp"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="@color/primary"
        android:textStyle="bold"
        tools:text="A" />

    <TextView
        android:id="@+id/tvName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/tvHeader"
        android:background="?android:attr/selectableItemBackground"
        android:padding="16dp"
        android:textAppearance="?android:attr/textAppearanceMedium"
        tools:text="Adam" />

</RelativeLayout>

适配器（2018年Kotlin版）：

class ContactAdapter @Inject constructor() : RecyclerView.Adapter<ContactAdapter.ViewHolder>() {

    var onItemClick: ((Contact) -> Unit)? = null
    var contacts = emptyList<Contact>()

    override fun getItemCount(): Int {
        return contacts.size
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        return ViewHolder(LayoutInflater.from(parent.context).inflate(R.layout.item_contact, parent, false))
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val name = contacts[position].name
        holder.header.text = name.substring(0, 1)
        holder.name.text = name

        // if not first item, check if item above has the same header
        if (position > 0 && contacts[position - 1].name.substring(0, 1) == name.substring(0, 1)) {
            holder.headerTextView.visibility = View.GONE
        } else {
            holder.headerTextView.visibility = View.VISIBLE
        }
    }

    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val headerTextView: TextView = itemView.tvHeader
        val nameTextView: TextView = itemView.tvName

        init {
            itemView.setOnClickListener {
                onItemClick?.invoke(contacts[adapterPosition])
            }
        }
    }
}

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可能也有帮助：RecyclerView itemClickListener in Kotlin

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旧Java适配器版本：

public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.DataViewHolder> {

    private List<Contact> mData;

    @Inject
    public RecyclerAdapter() {
        mData = new ArrayList<>();
    }

    public void setData(List<Contact> data) {
        mData = data;
    }

    public Contact getItem(int position){
        return mData.get(position);
    }

    @Override
    public DataViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_contact, parent, false);
        return new DataViewHolder(itemView);
    }

    @Override
    public void onBindViewHolder(final DataViewHolder holder, int position) {
        Contact contact = mData.get(position);
        holder.headerTextView.setText(contact.getName().substring(0, 1));
        holder.nameTextView.setText(contact.getName());

        // if not first item check if item above has the same header
        if (position > 0 && mData.get(position - 1).getName().substring(0, 1).equals(contact.getName().substring(0, 1))) {
            holder.headerTextView.setVisibility(View.GONE);
        } else {
            holder.headerTextView.setVisibility(View.VISIBLE);
        }
    }

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

    public class DataViewHolder extends RecyclerView.ViewHolder {

        @BindView(R.id.text_header)
        TextView headerTextView;
        @BindView(R.id.text_name)
        TextView nameTextView;

        public DataViewHolder(View itemView) {
            super(itemView);
            ButterKnife.bind(this, itemView);
        }
    }
}