Android中ListView使用示例介绍

2024-11-29 17:05:03

一、具体思路

1、创建Listview控件

2、创建子布局

创建数据库

主方法调用数据库继承类且初始化数据库，写入数据

MyDatabaseHelper databaseHelper = new MyDatabaseHelper(this,"Co.db",null,1);

SQLiteDatabase db = databaseHelper.getWritableDatabase();

SQLiteDatabase db2 = databaseHelper.getReadableDatabase();

3、写入

ContentValues values = new ContentValues();
values.put("Code","1");
values.put("Name","Admin");
values.put("Post","32");
values.put("Tel","123456789");
db.insert("employee",null,values);
values.clear();
values.put("Code","2");
values.put("Name","Admin1");
values.put("Post","22");
values.put("Tel","23342e");
db.insert("employee",null,values);

4、读取

Cursor cursor = db2.query("Employee",null,null,null,null,null,null);
arrayList = new ArrayList<>();
if (cursor.moveToFirst()) {
    do {
        name = cursor.getString(cursor.getColumnIndex("Name"));
        code = cursor.getString(cursor.getColumnIndex("Code"));
        post = cursor.getString(cursor.getColumnIndex("Post"));
        tel = cursor.getString(cursor.getColumnIndex("Tel"));
        System.out.println("查找到的值:"+ name +"---"+ code +"---"+ post +"---"+ tel);
        Employee employee=new Employee(name, tel, post, code);
        arrayList.add(employee);

    }while (cursor.moveToNext());
}

5、创建对象，构造器，GETSET方法

6、创建Adapter

二、具体实施

1、适配器

lv.setAdapter(new BaseAdapter() {
    @Override
    public int getCount() {
        return arrayList.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View view;
        if (convertView==null){
            view=View.inflate(getBaseContext(),R.layout.listitem,null);
        }else{
            view=convertView;
        }
        Employee ee=(Employee) arrayList.get(position);
        TextView eename=view.findViewById(R.id.name);
        TextView eedianhua=view.findViewById(R.id.dianhua);
        TextView eezhiwei=view.findViewById(R.id.zhiwei);
        TextView eekahao=view.findViewById(R.id.kahao);
        eename.setText(ee.getName());
        eedianhua.setText(ee.getTel());
        eezhiwei.setText(ee.getPost());
        eekahao.setText(ee.getCode());
        return view;
    }
});

2、数据库

public class MyDatabaseHelper extends SQLiteOpenHelper {
    public static final String CREATE_Employees = "create table employee ("
            + "Code text, "
            + "Name text unique, "
            + "Post text, "
            + "Tel text)";

    private Context mContext;
    public MyDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory
            factory, int version) {
        super(context, name, factory, version);
        mContext = context;
    }
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_Employees);
        Toast.makeText(mContext, "Create succeeded", Toast.LENGTH_SHORT).show();
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }
}

3、对象

package com.example.a4_7_1_lv;

public class Employee {
    private String name;
    private String tel;
    private String post;
    private String code;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getTel() {
        return tel;
    }

    public void setTel(String tel) {
        this.tel = tel;
    }

    public String getPost() {
        return post;
    }

    public void setPost(String post) {
        this.post = post;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public Employee(String name, String tel, String post, String code) {
        this.name = name;
        this.tel = tel;
        this.post = post;
        this.code = code;
    }

    public Employee() {
    }
}

4、等等等等

三、案例分享

activity_main.xml

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

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

</RelativeLayout>

listitem.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="姓名"
            android:textSize="30dp"/>
        <TextView
            android:layout_marginLeft="30dp"
            android:id="@+id/name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text=""
            android:textSize="30dp"/>
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="电话"
                android:layout_marginLeft="100dp"
                android:textSize="30dp"/>
            <TextView
                android:layout_marginLeft="30dp"
                android:id="@+id/dianhua"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text=""
                android:textSize="30dp"/>
</LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="职位"
            android:textSize="30dp"/>
        <TextView
            android:layout_marginLeft="30dp"
            android:id="@+id/zhiwei"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text=""
            android:textSize="30dp"/>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="卡号"
            android:layout_marginLeft="100dp"
            android:textSize="30dp"/>
        <TextView
            android:layout_marginLeft="30dp"
            android:id="@+id/kahao"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text=""
            android:textSize="30dp"/>
    </LinearLayout>
</LinearLayout>

MyDatabaseHelper.java

package com.example.a4_7_1_lv;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

public class MyDatabaseHelper extends SQLiteOpenHelper {
    public static final String CREATE_Employees = "create table employee ("
            + "Code text, "
            + "Name text unique, "
            + "Post text, "
            + "Tel text)";

    private Context mContext;
    public MyDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory
            factory, int version) {
        super(context, name, factory, version);
        mContext = context;
    }
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_Employees);
        Toast.makeText(mContext, "Create succeeded", Toast.LENGTH_SHORT).show();
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }
}

MainActivity.java

package com.example.a4_7_1_lv;

import androidx.appcompat.app.AppCompatActivity;

import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    private ListView lv;
    private MyDatabaseHelper databaseHelper;
    private SQLiteDatabase db;
    private SQLiteDatabase db2;
    private ArrayList arrayList;
    private String name;
    private String code;
    private String post;
    private String tel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv = findViewById(R.id.list);
    }

    @Override
    protected void onStart() {
        super.onStart();
        MyDatabaseHelper databaseHelper = new MyDatabaseHelper(this,"Co.db",null,1);
        db = databaseHelper.getWritableDatabase();
        db2 = databaseHelper.getReadableDatabase();
        DBInsert();
        Cursor cursor = db2.query("Employee",null,null,null,null,null,null);
        arrayList = new ArrayList<>();
        if (cursor.moveToFirst()) {
            do {
                name = cursor.getString(cursor.getColumnIndex("Name"));
                code = cursor.getString(cursor.getColumnIndex("Code"));
                post = cursor.getString(cursor.getColumnIndex("Post"));
                tel = cursor.getString(cursor.getColumnIndex("Tel"));
                System.out.println("查找到的值:"+ name +"---"+ code +"---"+ post +"---"+ tel);
                Employee employee=new Employee(name, tel, post, code);
                arrayList.add(employee);

            }while (cursor.moveToNext());
        }
        lv.setAdapter(new BaseAdapter() {
            @Override
            public int getCount() {
                return arrayList.size();
            }

            @Override
            public Object getItem(int position) {
                return null;
            }

            @Override
            public long getItemId(int position) {
                return 0;
            }

            @Override
            public View getView(int position, View convertView, ViewGroup parent) {
                View view;
                if (convertView==null){
                    view=View.inflate(getBaseContext(),R.layout.listitem,null);
                }else{
                    view=convertView;
                }
                Employee ee=(Employee) arrayList.get(position);
                TextView eename=view.findViewById(R.id.name);
                TextView eedianhua=view.findViewById(R.id.dianhua);
                TextView eezhiwei=view.findViewById(R.id.zhiwei);
                TextView eekahao=view.findViewById(R.id.kahao);
                eename.setText(ee.getName());
                eedianhua.setText(ee.getTel());
                eezhiwei.setText(ee.getPost());
                eekahao.setText(ee.getCode());
                return view;
            }
        });
    }

    private void DBInsert() {
        ContentValues values = new ContentValues();
        values.put("Code","1");
        values.put("Name","Admin");
        values.put("Post","32");
        values.put("Tel","123456789");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","2");
        values.put("Name","Admin1");
        values.put("Post","22");
        values.put("Tel","23342e");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","4");
        values.put("Name","Admin13");
        values.put("Post","2sda2");
        values.put("Tel","233asd42e");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","Code");
        values.put("Name","Name");
        values.put("Post","Post");
        values.put("Tel","Tel");
        db.insert("employee",null,values);
    }
}

Employee.java

package com.example.a4_7_1_lv;

import androidx.appcompat.app.AppCompatActivity;

import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    private ListView lv;
    private MyDatabaseHelper databaseHelper;
    private SQLiteDatabase db;
    private SQLiteDatabase db2;
    private ArrayList arrayList;
    private String name;
    private String code;
    private String post;
    private String tel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv = findViewById(R.id.list);
    }

    @Override
    protected void onStart() {
        super.onStart();
        MyDatabaseHelper databaseHelper = new MyDatabaseHelper(this,"Co.db",null,1);
        db = databaseHelper.getWritableDatabase();
        db2 = databaseHelper.getReadableDatabase();
        DBInsert();
        Cursor cursor = db2.query("Employee",null,null,null,null,null,null);
        arrayList = new ArrayList<>();
        if (cursor.moveToFirst()) {
            do {
                name = cursor.getString(cursor.getColumnIndex("Name"));
                code = cursor.getString(cursor.getColumnIndex("Code"));
                post = cursor.getString(cursor.getColumnIndex("Post"));
                tel = cursor.getString(cursor.getColumnIndex("Tel"));
                System.out.println("查找到的值:"+ name +"---"+ code +"---"+ post +"---"+ tel);
                Employee employee=new Employee(name, tel, post, code);
                arrayList.add(employee);

            }while (cursor.moveToNext());
        }
        lv.setAdapter(new BaseAdapter() {
            @Override
            public int getCount() {
                return arrayList.size();
            }

            @Override
            public Object getItem(int position) {
                return null;
            }

            @Override
            public long getItemId(int position) {
                return 0;
            }

            @Override
            public View getView(int position, View convertView, ViewGroup parent) {
                View view;
                if (convertView==null){
                    view=View.inflate(getBaseContext(),R.layout.listitem,null);
                }else{
                    view=convertView;
                }
                Employee ee=(Employee) arrayList.get(position);
                TextView eename=view.findViewById(R.id.name);
                TextView eedianhua=view.findViewById(R.id.dianhua);
                TextView eezhiwei=view.findViewById(R.id.zhiwei);
                TextView eekahao=view.findViewById(R.id.kahao);
                eename.setText(ee.getName());
                eedianhua.setText(ee.getTel());
                eezhiwei.setText(ee.getPost());
                eekahao.setText(ee.getCode());
                return view;
            }
        });
    }

    private void DBInsert() {
        ContentValues values = new ContentValues();
        values.put("Code","1");
        values.put("Name","Admin");
        values.put("Post","32");
        values.put("Tel","123456789");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","2");
        values.put("Name","Admin1");
        values.put("Post","22");
        values.put("Tel","23342e");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","4");
        values.put("Name","Admin13");
        values.put("Post","2sda2");
        values.put("Tel","233asd42e");
        db.insert("employee",null,values);
        values.clear();
        values.put("Code","Code");
        values.put("Name","Name");
        values.put("Post","Post");
        values.put("Tel","Tel");
        db.insert("employee",null,values);
    }
}

到此这篇关于Android中ListView使用示例介绍的文章就介绍到这了,更多相关Android ListView使用内容请搜索我们以前的文章或继续浏览下面的相关文章希望大家以后多多支持我们！

Android studio listview实现列表数据显示数据循环显示效果

Android studio listview实现列表数据显示样式不好看!想要好看的样式可以私我,我加! item.xml <?xml version="1.0" encoding="utf-8"?>  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation=&q
Android ListView 实例讲解清晰易懂

一.前言在某些场景下,单一文字的ListView Item已不适合当前需求,因此需要我们自定义Item布局来满足需求.下面我们来实现一个带图标和文字的Item. 二.代码展示 1.定义包含ListView的布局文件activity_main.xml,Activity在onCreate()时加载. <?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.Con
Android中ListView使用示例介绍

目录一.具体思路 1.创建Listview控件 3.写入 4.读取 5.创建对象,构造器,GETSET方法二.具体实施 1.适配器 2.数据库 3.对象 4.等等等等三.案例分享 activity_main.xml listitem.xml MyDatabaseHelper.java MainActivity.java Employee.java 简单ListView实例数据库读取数据存入ListView 一.具体思路 1.创建Listview控件 2.创建子布局创建数据库主方法调用
Android中ListView异步加载图片错位、重复、闪烁问题分析及解决方案

Android ListView异步加载图片错位.重复.闪烁分析以及解决方案,具体问题分析以及解决方案请看下文. 我们在使用ListView异步加载图片的时候,在快速滑动或者网络不好的情况下,会出现图片错位.重复.闪烁等问题,其实这些问题总结起来就是一个问题,我们需要对这些问题进行ListView的优化. 比如ListView上有100个Item,一屏只显示10个Item,我们知道getView()中convertView是用来复用View对象的,因为一个Item的对应一个View对象,而Ima
Android中Listview点击item不变颜色及设置listselector 无效的解决方案

这是同一个问题,Listview中点击item是会变颜色的,因为listview设置了默认的listselector,有一个默认的颜色,同理如果点击没颜色变化我们怎么设置listselector也不会变颜色的. 但是在我们的开发过程中,我们可能会碰到这样的问题listview点击不变颜色,总结了一下大概有这几种原因: 1.item的layout设置background颜色值,去掉背景颜色即可 2.listview中listselector属性的效果被覆盖了,比如列表的Item为一个占满单元格的I
Android中Listview点赞功能的实现

最近这段时间一直在看Android,利用Listview去实现点赞功能,下面给大家介绍下基本思路. 基本思路: 进入界面–>获取数据–> 在Listview中显示–> 通过map集合(position,boolean)保存每一行是否被点击–> 利用实体类去保存相应的对象–> get/set方法进行相应值得改变–> 点击一次,相应的数量加1 只实现了点赞功能,踩和赞基本类似. 具体实现如下: 继承自BaseAdapter package com.gz.test_listv
Android 中ListView setOnItemClickListener点击无效原因分析

前言最近在做项目的过程中,在使用listview的时候遇到了设置item监听事件的时候在没有回调onItemClick 方法的问题.我的情况是在item中有一个Button按钮.所以不会回调.上百度找到了解决办法有两种,如下: 1.在checkbox.button对应的view处加android:focusable="false" 复制代码代码如下: android:clickable="false" android:focusableInTouchMode=&
Android中ListView绑定CheckBox实现全选增加和删除功能(DEMO)

ListView控件还是挺复杂的,也是项目中应该算是比较常用的了,所以写了一个小Demo来讲讲,主要是自定义adapter的用法,加了很多的判断等等等等-.我们先来看看实现的效果吧! 好的,我们新建一个项目LvCheckBox 我们事先先把这两个布局写好吧,一个是主布局,还有一个listview的item.xml,相信不用多说 activity_main.xml <LinearLayout xmlns:android="http://schemas.android.com/apk/res/
Android中ListView的item点击没有反应的解决方法

如果stu_item.xml里面包括button或者checkbox等控件,默认情况下list的item会失去焦点,导致无法响应item的事件,最常用的解决办法是在stu_item.xml的布局文件中设置descendantFocusability属性. 该属性是当一个为view获取焦点时,定义viewGroup和其子控件两者之间的关系. 属性的值有三种: beforeDescendants:viewgroup会优先其子类控件而获取到焦点 afterDescendants:viewgroup只有
Android中Listview下拉刷新和上拉加载更多的多种实现方案

listview经常结合下来刷新和上拉加载更多使用,本文总结了三种常用到的方案分别作出说明. 方案一:添加头布局和脚布局 android系统为listview提供了addfootview和addheadview两个API.这样可以直接自定义一个View,以添加视图的形式实现下来刷新和上拉加载. 实现步骤 1.创建一个类继承ListView:class PullToRefreshListView extends ListView: 2.在构造方法中添加HeadView:addHeaderVi
Android中ListView + CheckBox实现单选、多选效果

还是先来看看是不是你想要的效果: 不废话,直接上代码,很简单,代码里都有注释 1 单选 public class SingleActivity extends AppCompatActivity { private ListView listView; private ArrayList<String> groups; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInsta
探究Android中ListView复用导致布局错乱的解决方案

首先来说一下具体的需求是什么样的: 需求如图所示,这里面有ABCD四个选项的题目,当点击A选项,如果A是正确的答案,则变成对勾的图案,如果是错误答案,则变成错误的图案,这里当时在写的时候觉得很简单,只要是在点击的时候判断我点击的选项与正确答案是否一样,是一样就将图片换成正确的样式,如果不一样就换成错误的样式,于是我便写了下面的代码(只贴出了核心Adapter中的代码) package com.fizzer.anbangproject_dahuo_test.Adapter; import andr