androidbook

Just add this class in your package  package com.plzf1.rollearn ; import android.app.Application ; import android.content.SharedPreferences ; public class MyApplication extends Application { public static final String MENULIST = "menulist" ; public static final String VEGLIST = "veglist" ; public static final String CARTLIST = "cartlist" ; public static final String FRUITLIST = "fruitlist" ; @Override public void onCreate () { super .onCreate() ; } public void saveIntoPrefs (String key , String value) { SharedPreferences prefs = getSharedPreferences(Fconstants.PREF_NAME , MODE_PRIVATE ) ; SharedPreferences.Editor edit = prefs.edit() ; edit.putString(key , value) ; edit.commit() ; } public void saveIntoPrefs (String key , int value) { SharedPreferences prefs = getSharedPreferences(Fconstants.PREF_NAME , MODE_PRIVATE ) ; SharedPreferences.Edit

for use room data base in android you need to setup faw things first you have to add two deandancy in your gradel file  implementation "android.arch.persistence.room:runtime:1.0.0-beta2" annotationProcessor "android.arch.persistence.room:compiler:1.0.0-beta2" then make a entity class and dao class in your file structure  Data base class   package com.plzf1.rollearn.database; import android.arch.persistence.room.Database; import android.arch.persistence.room.RoomDatabase; @Database(entities = User.class , version = 1) public abstract class MyDataBase extends RoomDatabase {     public abstract UserDao userDao(); } Entity Class android.arch.persistence.room.ColumnInfo; import android.arch.persistence.room.Entity; import android.arch.persistence.room.PrimaryKey; @Entity(tableName = "user") public class User {     @PrimaryKey(autoGenerate = true)     private int userid;     @C