万能适配器basequickadapter + recycleview实现单选并且默认选择第一个

1、首先，确保您已经添加了BaseQuickAdapter和RecyclerView的依赖项。您可以在项目的build.gradle文件中添加以下依赖项：

dependencies {
    implementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:3.0.4'
    implementation 'androidx.recyclerview:recyclerview:1.2.1'
}

2、创建一个数据模型类来表示每个列表项的数据。例如，假设您有一个名为Item的数据类：

public class Item {
    private String name;
    private boolean isSelected;
 
    public Item(String name) {
        this.name = name;
        this.isSelected = false;
    }
 
    public String getName() {
        return name;
    }
 
    public boolean isSelected() {
        return isSelected;
    }
 
    public void setSelected(boolean selected) {
        isSelected = selected;
    }
}

3、创建一个Adapter类，继承自BaseQuickAdapter。在Adapter中，您需要处理单选逻辑以及默认选择第一个项的逻辑：

public class ItemAdapter extends BaseQuickAdapter<Item, BaseViewHolder> {
 
    public ItemAdapter(@Nullable List<Item> data) {
        super(R.layout.item_layout, data);
    }
 
    @Override
    protected void convert(BaseViewHolder helper, Item item) {
        helper.setText(R.id.text_view, item.getName());
        // 设置选中状态的背景色
        if (item.isSelected()) {
            helper.itemView.setBackgroundColor(ContextCompat.getColor(mContext, R.color.selected_color));
        } else {
            helper.itemView.setBackgroundColor(Color.TRANSPARENT);
        }
    }
 
    public void setItemSelected(int position) {
        for (int i = 0; i < getData().size(); i++) {
            getData().get(i).setSelected(i == position);
        }
        notifyDataSetChanged();
    }
}

4、在您的Activity或Fragment中，初始化RecyclerView和Adapter，并设置默认选择第一个项：

public class MainActivity extends AppCompatActivity {
 
    private RecyclerView recyclerView;
    private ItemAdapter adapter;
    private List<Item> itemList = new ArrayList<>();
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        recyclerView = findViewById(R.id.recycler_view);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
 
        // 初始化数据
        for (int i = 0; i < 10; i++) {
            itemList.add(new Item("Item " + (i + 1)));
        }
 
        // 创建Adapter并设置默认选中第一个项
        adapter = new ItemAdapter(itemList);
        adapter.setItemSelected(0);
 
        recyclerView.setAdapter(adapter);
 
        // 设置RecyclerView的点击事件
        adapter.setOnItemClickListener((adapter, view, position) -> {
            adapter.setSelected(position);
        });
    }
}