Android Listview ArrayAdapter example

The use of ListView can be roughly divided into four steps: adding the ListView component, storing data, setting the layout file of the list item, loading data/resources for display, and adding monitoring.

This article mainly talks about the simplest usage of ArrayAdapter

The example effect is as follows:

 main layout file

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".MainActivity">


    <ListView
            android:id="@+id/lvTest"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
</LinearLayout>

The layout file of list_item (of course, it is also possible to use ArrayAdapter without defining this item layout. You can use the android.R.layout.simple_list_item_1 that comes with the system):

<?xml version="1.0" encoding="UTF-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:textColor="#FF00FF"
          android:padding="15dp"
          android:textSize="16sp"
>
</TextView>

MainActivity.java

package com.example.ArrayAdapter;

import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;


public class MainActivity extends AppCompatActivity {

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

        //1. 准备数据源
        ListView  listview = findViewById(R.id.lvTest);
        final String[] citys = {"上海","北京","天津","江苏","河南","西藏","新疆","湖南","湖北"};
/*       List<String> listdata = new ArrayList<String>();
        listdata.add("上海");
        listdata.add("北京");
        listdata.add("天津");
        listdata.add("江苏");
 */
        //2.将数据源添加到适配器中 android.R.layout.simple_list_item_1 为内置默认Item布局，这里可以自定义比如：R.layout.list_item
        ArrayAdapter arrayAdapter = new ArrayAdapter(MainActivity.this, R.layout.list_item, citys); //listdata和citys均可
        //3. 将适配器中的数据添加到ListView 中
        listview.setAdapter(arrayAdapter);

        //为 ListView 的列表项添加鼠标点击事件
        listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            /**
             * @param adapterView 发生单击事件的列表项 ListView
             * @param view        被单击控件 view
             * @param i           在列表项中的位置 position
             * @param l           被单击列表项的行ID
             */
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                String Tag = "onItemClick======";
                Log.d(Tag, "position=" + i);
                Log.d(Tag, "行 ID" + l);
                Toast.makeText(MainActivity.this, citys[i], Toast.LENGTH_SHORT).show();

            }
        });
    }
}