package helper;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DBHelper extends SQLiteOpenHelper {
private static final String TABLENAME="News";
private static final int VERSION = 1;
public DBHelper(Context context) {
super( context, TABLENAME, null, VERSION );
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL( "create table news(id Integer primary key autoincrement,data text)" );
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
//dao层
package com.example.dell.ykmoni01;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import com.google.gson.Gson;
import java.util.List;
import bean.NewsBean;
import helper.DBHelper;
public class Dao {
private SQLiteDatabase db;
private static final String TABLENAME = "news";
private static final String DATA = "data";
public Dao(Context context) {
DBHelper dbHelper = new DBHelper( context );
db = dbHelper.getWritableDatabase();
}
//添加
public long insert(String data){
ContentValues values = new ContentValues();
values.put( DATA, data );
return db.insert( TABLENAME,null, values);
}
//查询
public List<NewsBean.ResultBean.DataBean> queryAll(){
String dataSql="";
try {
Cursor cursor = db.rawQuery("select data from news", null);
while(cursor.moveToNext()){
dataSql = cursor.getString( cursor.getColumnIndex( DATA ) );
}
NewsBean newsList = new Gson().fromJson( dataSql, NewsBean.class );
return newsList.getResult().getData();
}catch (Exception e){
}
return null;
}
}
//点击收藏存入数据库 调用insert方法
public void onClick(View v) {
Dao dao = new Dao( News.this );
dao.insert( data );
Toast.makeText( News.this,"收藏成功",Toast.LENGTH_SHORT ).show();
}
//查询我的收藏 查询数据库放入listview集合
listView = findViewById( R.id.listview_sc );
Dao dao = new Dao( Sc.this );
List<NewsBean.ResultBean.DataBean> newsBeans = dao.queryAll();
MyScAdapter myScAdapter = new MyScAdapter( Sc.this, newsBeans );
listView.setAdapter( myScAdapter );