Question

我一直在使用cursorler和recyclerview。

我有一个查询的游标对象（从加载器传递）和一个头字符串数组[]。

String headers[] = {"apples", "bananas"...};

现在我想将项目显示为

Apples
cursor row 1
cursor row 2
cursor row 3
Bananas
cursor row 4
cursor row 5

我不想使用getItemCount（）方法进行调整。因此，计划以适当的长度传递单个光标。

一种可能的方法是使用MatrixCursor和MergeCursor添加虚拟行，如下所述：Adding rows into Cursor manually。这很好但是MergeCursor一个接一个地对齐标题和光标数据。

想要探索使用正确的标题和项目位置来实现最终光标的方法。

Answer 1

您可以使用库SectionedRecyclerViewAdapter将数据分组到各个部分，并为每个部分添加标题。

首先创建一个Section类：

class MySection extends StatelessSection {

    String title;
    List<String> list;

    public MySection(String title, List<String> 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
    }

    @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.title.setText(list.get(position));
    }

    @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();

// Add your Sections to the adapter
sectionAdapter.addSection(new MySection(headers[0], applesList));
sectionAdapter.addSection(new MySection(headers[1], bananasList));

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

通过上面的示例，您必须处理如何将Cursor转换为List<String>，但您可以更改MySection类以接收Cursor而不是List<String> }。

Recylerview，CursorAdapter之间有Header视图

1 个答案: