zoukankan      html  css  js  c++  java
  • android中SQLite实现

    SQLite操作类:

    package com.example.administrator.myapplication;
    
    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;
    
    public class BookmarkSQLiteOpenHelper extends SQLiteOpenHelper{
        public BookmarkSQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){
            super(context,name,factory,version);
        }
    
        @Override
        public void onCreate(SQLiteDatabase db){
            String sql="create table bookmark(id integer primary key autoincrement,favicon varchar(100),title varchar(100),url varchar(100))";
            db.execSQL(sql);
        }
    
        @Override
        public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){}
    }

    SQLite初始化:

    bookmarkSQLiteOpenHelper=new BookmarkSQLiteOpenHelper(this,"browser.db",null,1);

    SQLite插入数据:

    void insertBookmark(Bookmark bookmark){
            SQLiteDatabase db=bookmarkSQLiteOpenHelper.getWritableDatabase();
            db.execSQL("insert into bookmark(favicon,title,url)values(?,?,?)",new String[]{bookmark.getFavicon(),bookmark.getTitle(),bookmark.getUrl()});
        }

     SQLite查询数据:

    bookmarkSQLiteOpenHelper=new BookmarkSQLiteOpenHelper(this,"browser.db",null,1);
            SQLiteDatabase db=bookmarkSQLiteOpenHelper.getReadableDatabase();
            Cursor cursor=db.rawQuery("select * from bookmark",null);
            while(cursor.moveToNext()){
                String favicon=cursor.getString(cursor.getColumnIndex("favicon"));
                String title=cursor.getString(cursor.getColumnIndex("title"));
                String url=cursor.getString(cursor.getColumnIndex("url"));
    
                Bitmap bitmap=null;
                try{
                    String sdcard_path=Environment.getExternalStorageDirectory().getCanonicalPath();
                    String bitmap_path=sdcard_path+"/xinyuelantuBrowserFavicon/"+favicon+".jpg";
                    bitmap=BitmapFactory.decodeFile(bitmap_path);
                }
                catch(IOException e){}
                Map<String,Object> map_bookmark=new HashMap<String,Object>();
                map_bookmark.put("favicon",bitmap);
                map_bookmark.put("title",title);
                map_bookmark.put("url",url);
                arraylist_bookmark.add(map_bookmark);
            }
  • 相关阅读:
    网络爬虫技术总结
    MongoDB(7):集群部署实践,包含复制集,分片
    MongoDB(6):简单配置,环境变量,关闭服务
    Mongod(5):启动命令mongod参数说明
    MongoDB(4):多种方式关闭服务命令
    Linux下的Source命令及脚本的执行方式解析
    linux第一天
    echarts 各种细节问题
    MongoDB(3):小的细节问题
    获取用户Ip地址通用方法常见安全隐患(HTTP_X_FORWARDED_FOR)
  • 原文地址:https://www.cnblogs.com/zqxLonely/p/5462549.html
Copyright © 2011-2022 走看看