如何在Android应用中动态管理ItemList

在Android应用中动态管理ItemList，通常需要使用适配器（Adapter）和列表视图（ListView 或 RecyclerView）

创建一个数据模型类（Model Class）：

public class Item {
    private String title;
    private String description;

    public Item(String title, String description) {
        this.title = title;
        this.description = description;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }
}

创建一个自定义适配器（Custom Adapter）：

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.List;

public class CustomAdapter extends BaseAdapter {
    private Context context;
    private List<Item> itemList;

    public CustomAdapter(Context context, List<Item> itemList) {
        this.context = context;
        this.itemList = itemList;
    }

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

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

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.list_item, parent, false);
        }

        TextView titleTextView = convertView.findViewById(R.id.title);
        TextView descriptionTextView = convertView.findViewById(R.id.description);

        titleTextView.setText(itemList.get(position).getTitle());
        descriptionTextView.setText(itemList.get(position).getDescription());

        return convertView;
    }
}

在布局文件中添加ListView或RecyclerView：

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

在Activity或Fragment中初始化适配器并设置给ListView或RecyclerView：

import android.os.Bundle;
import android.widget.ListView;

import androidx.appcompat.app.AppCompatActivity;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private ListView listView;
    private CustomAdapter adapter;
    private List<Item> itemList;

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

        listView = findViewById(R.id.listView);

        itemList = new ArrayList<>();
        itemList.add(new Item("Item 1", "This is item 1"));
        itemList.add(new Item("Item 2", "This is item 2"));
        itemList.add(new Item("Item 3", "This is item 3"));

        adapter = new CustomAdapter(this, itemList);
        listView.setAdapter(adapter);
    }
}

动态添加、删除或更新列表项：

// 添加一个新项
Item newItem = new Item("New Item", "This is a new item");
itemList.add(newItem);
adapter.notifyDataSetChanged();

// 删除一个项
itemList.remove(0);
adapter.notifyDataSetChanged();

// 更新一个项
Item updatedItem = itemList.get(0);
updatedItem.setTitle("Updated Title");
updatedItem.setDescription("Updated Description");
adapter.notifyDataSetChanged();

这样，你就可以在Android应用中动态管理ItemList了。请根据实际情况调整代码，例如使用RecyclerView替换ListView。

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