Android：BaseAdapter 怎么用？

public class MyAdapter extends BaseAdapter {
    private Context context;
    private List<String> dataList;

    public MyAdapter(Context context, List<String> dataList) {
        this.context = context;
        this.dataList = dataList;
    }

    @Override
    public int getCount() {
        return dataList.size();
    }

    @Override
    public Object getItem(int position) {
        return dataList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder viewHolder;
        if (convertView == null) {
            convertView = LayoutInflater.from(context).inflate(R.layout.item_layout, parent, false);
            viewHolder = new ViewHolder();
            viewHolder.textView = convertView.findViewById(R.id.text_view);
            convertView.setTag(viewHolder);
        } else {
            viewHolder = (ViewHolder) convertView.getTag();
        }
        viewHolder.textView.setText(dataList.get(position));
        return convertView;
    }

    private static class ViewHolder {
        TextView textView;
    }
}

    android:id="@+id/list_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

    android:id="@+id/text_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:textSize="16sp"
    android:padding="10dp"/>

public class MainActivity extends AppCompatActivity {
    private ListView listView;
    private List<String> dataList = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listView = findViewById(R.id.list_view);

        // 添加数据
        for (int i = 1; i <= 20; i++) {
            dataList.add("这是第" + i + "个项目");
        }

        // 使用自定义Adapter
        MyAdapter adapter = new MyAdapter(this, dataList);
        listView.setAdapter(adapter);
    }
}