Android中ListView使用示例介绍

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




    


listitem.xml



    
        
        
            
            

    
        
        
        
        
    

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使用内容请搜索脚本之家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脚本之家!

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