greendao实现增删改查

说明：最近碰到一个需求，在安卓上使用greendao框架，实现增删改查数据

效果图：
在这里插入图片描述

step1:

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {repositories {google()jcenter()mavenCentral()}dependencies {classpath "com.android.tools.build:gradle:4.1.2"classpath 'org.greenrobot:greendao-gradle-plugin:3.3.0'// NOTE: Do not place your application dependencies here; they belong// in the individual module build.gradle files}
}allprojects {repositories {google()jcenter()}
}task clean(type: Delete) {delete rootProject.buildDir
}

step2:

plugins {id 'com.android.application'id 'org.greenrobot.greendao'
}android {compileSdkVersion 32defaultConfig {applicationId "com.example.iosdialogdemo"minSdkVersion 16targetSdkVersion 32versionCode 1versionName "1.0"testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"}buildTypes {release {minifyEnabled falseproguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'}}compileOptions {sourceCompatibility JavaVersion.VERSION_1_8targetCompatibility JavaVersion.VERSION_1_8}
}greendao {schemaVersion 7daoPackage 'com.example.iosdialogdemo'targetGenDir 'src/main/java'
}dependencies {implementation 'androidx.appcompat:appcompat:1.1.0'implementation 'com.google.android.material:material:1.1.0'implementation 'androidx.constraintlayout:constraintlayout:1.1.3'testImplementation 'junit:junit:4.+'androidTestImplementation 'androidx.test.ext:junit:1.1.1'androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'implementation 'org.greenrobot:greendao:3.2.2'implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0'}

step3:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.example.iosdialogdemo"><applicationandroid:name=".GreenApp"android:allowBackup="true"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:roundIcon="@mipmap/ic_launcher_round"android:supportsRtl="true"android:theme="@style/Theme.IosDialogDemo"><activity android:name=".MainActivity"android:exported="true"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application></manifest>

step4:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"android:layout_margin="8dp"android:orientation="vertical"><LinearLayoutandroid:id="@+id/linearLayout2"android:layout_width="match_parent"android:layout_height="wrap_content"android:gravity="center_vertical"android:orientation="horizontal"><EditTextandroid:id="@+id/etLanguage"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_weight="1"android:paddingRight="8dp" /><Buttonandroid:id="@+id/btn_add"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_weight="3"android:backgroundTint="@android:color/holo_purple"android:text="新增"android:textColor="@android:color/white" /><Buttonandroid:id="@+id/btn_update"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_weight="3"android:backgroundTint="@android:color/holo_purple"android:text="修改"android:textColor="@android:color/white" /></LinearLayout><androidx.recyclerview.widget.RecyclerViewandroid:id="@+id/rvLanguage"android:layout_width="match_parent"android:layout_height="match_parent"tools:listitem="@layout/item" /></LinearLayout>

step5:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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="wrap_content"android:layout_marginBottom="16dp"android:gravity="center_vertical"android:orientation="horizontal"><TextViewandroid:id="@+id/tvOrderNumber"android:layout_width="100dp"android:layout_height="wrap_content"android:layout_marginEnd="16dp"android:text="1"android:textColor="@color/white"android:background="@color/purple_200"app:layout_constraintBottom_toBottomOf="@+id/tvLanguage"app:layout_constraintEnd_toStartOf="@+id/tvLanguage"app:layout_constraintHorizontal_bias="0.0"app:layout_constraintHorizontal_chainStyle="spread_inside"app:layout_constraintStart_toStartOf="parent"app:layout_constraintTop_toTopOf="@+id/tvLanguage" /><TextViewandroid:id="@+id/tvLanguage"android:layout_width="0dp"android:layout_height="wrap_content"android:text="Bahasa"android:textColor="@color/white"android:background="@color/teal_200"app:layout_constraintBottom_toBottomOf="@+id/btnDelete"app:layout_constraintEnd_toStartOf="@+id/btnDelete"app:layout_constraintHorizontal_bias="0.5"app:layout_constraintStart_toEndOf="@+id/tvOrderNumber"app:layout_constraintTop_toTopOf="@+id/btnDelete" /><Buttonandroid:id="@+id/btnDelete"android:layout_width="50dp"android:layout_height="wrap_content"android:text="删除"android:backgroundTint="@android:color/holo_blue_dark"app:layout_constraintBottom_toBottomOf="parent"app:layout_constraintEnd_toEndOf="parent"app:layout_constraintHorizontal_bias="0.5"app:layout_constraintStart_toEndOf="@+id/tvLanguage"app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

step6:

package com.example.iosdialogdemo;import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.util.Log;import org.greenrobot.greendao.AbstractDaoMaster;
import org.greenrobot.greendao.database.StandardDatabase;
import org.greenrobot.greendao.database.Database;
import org.greenrobot.greendao.database.DatabaseOpenHelper;
import org.greenrobot.greendao.identityscope.IdentityScopeType;// THIS CODE IS GENERATED BY greenDAO, DO NOT EDIT.
/*** Master of DAO (schema version 7): knows all DAOs.*/
public class DaoMaster extends AbstractDaoMaster {public static final int SCHEMA_VERSION = 7;/** Creates underlying database table using DAOs. */public static void createAllTables(Database db, boolean ifNotExists) {UserDao.createTable(db, ifNotExists);}/** Drops underlying database table using DAOs. */public static void dropAllTables(Database db, boolean ifExists) {UserDao.dropTable(db, ifExists);}/*** WARNING: Drops all table on Upgrade! Use only during development.* Convenience method using a {@link DevOpenHelper}.*/public static DaoSession newDevSession(Context context, String name) {Database db = new DevOpenHelper(context, name).getWritableDb();DaoMaster daoMaster = new DaoMaster(db);return daoMaster.newSession();}public DaoMaster(SQLiteDatabase db) {this(new StandardDatabase(db));}public DaoMaster(Database db) {super(db, SCHEMA_VERSION);registerDaoClass(UserDao.class);}public DaoSession newSession() {return new DaoSession(db, IdentityScopeType.Session, daoConfigMap);}public DaoSession newSession(IdentityScopeType type) {return new DaoSession(db, type, daoConfigMap);}/*** Calls {@link #createAllTables(Database, boolean)} in {@link #onCreate(Database)} -*/public static abstract class OpenHelper extends DatabaseOpenHelper {public OpenHelper(Context context, String name) {super(context, name, SCHEMA_VERSION);}public OpenHelper(Context context, String name, CursorFactory factory) {super(context, name, factory, SCHEMA_VERSION);}@Overridepublic void onCreate(Database db) {Log.i("greenDAO", "Creating tables for schema version " + SCHEMA_VERSION);createAllTables(db, false);}}/** WARNING: Drops all table on Upgrade! Use only during development. */public static class DevOpenHelper extends OpenHelper {public DevOpenHelper(Context context, String name) {super(context, name);}public DevOpenHelper(Context context, String name, CursorFactory factory) {super(context, name, factory);}@Overridepublic void onUpgrade(Database db, int oldVersion, int newVersion) {Log.i("greenDAO", "Upgrading schema from version " + oldVersion + " to " + newVersion + " by dropping all tables");dropAllTables(db, true);onCreate(db);}}}

step7:

package com.example.iosdialogdemo;import java.util.Map;import org.greenrobot.greendao.AbstractDao;
import org.greenrobot.greendao.AbstractDaoSession;
import org.greenrobot.greendao.database.Database;
import org.greenrobot.greendao.identityscope.IdentityScopeType;
import org.greenrobot.greendao.internal.DaoConfig;import com.example.iosdialogdemo.User;import com.example.iosdialogdemo.UserDao;// THIS CODE IS GENERATED BY greenDAO, DO NOT EDIT./*** {@inheritDoc}* * @see org.greenrobot.greendao.AbstractDaoSession*/
public class DaoSession extends AbstractDaoSession {private final DaoConfig userDaoConfig;private final UserDao userDao;public DaoSession(Database db, IdentityScopeType type, Map<Class<? extends AbstractDao<?, ?>>, DaoConfig>daoConfigMap) {super(db);userDaoConfig = daoConfigMap.get(UserDao.class).clone();userDaoConfig.initIdentityScope(type);userDao = new UserDao(userDaoConfig, this);registerDao(User.class, userDao);}public void clear() {userDaoConfig.clearIdentityScope();}public UserDao getUserDao() {return userDao;}}

step8:

package com.example.iosdialogdemo;import android.app.Application;
import org.greenrobot.greendao.database.Database;/*** Created by rhodel on 8/15/2017.*/public class GreenApp extends Application {private DaoSession daoSession;@Overridepublic void onCreate() {super.onCreate();DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this, "notes-db");Database db = helper.getWritableDb();daoSession = new DaoMaster(db).newSession();}@Overridepublic void onTerminate() {super.onTerminate();daoSession.clear();}public DaoSession getDaoSession() {return daoSession;}
}

step9:

package com.example.iosdialogdemo;public interface ILanguageRecycleListener {void itemOnClick(int model,Long id,String title,int position);/* mode1 0:id,1:title,2:delete*/
}

step10:

package com.example.iosdialogdemo;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import androidx.annotation.NonNull;import androidx.recyclerview.widget.RecyclerView;import java.util.ArrayList;import java.util.List;public class LanguageRecycleAdapter extends RecyclerView.Adapter<LanguageViewHolder> {private List<User> languageList = new ArrayList<>();private ILanguageRecycleListener listener;public LanguageRecycleAdapter(List<User> languageList, ILanguageRecycleListener listener) {this.languageList = languageList;this.listener = listener;Log.e("TAG", "LanguageRecycleAdapter " + languageList.size());}public void setData(List<User> languageList2) {this.languageList = languageList2;}@NonNull@Overridepublic LanguageViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {LanguageViewHolder holder;View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, parent, false);holder = new LanguageViewHolder(view);return holder;}@Overridepublic void onBindViewHolder(@NonNull LanguageViewHolder holder, final int position) {holder.orderNumber.setText(String.valueOf(position));holder.language.setText(languageList.get(position).getName());holder.orderNumber.setText(String.valueOf(languageList.get(position).getId()));holder.btnDelete.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {listener.itemOnClick(2,languageList.get(position).getId(),languageList.get(position).getName(),position);}});holder.orderNumber.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {listener.itemOnClick(0,languageList.get(position).getId(),languageList.get(position).getName(),position);}});holder.language.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {listener.itemOnClick(1,languageList.get(position).getId(),languageList.get(position).getName(),position);}});}@Overridepublic int getItemCount() {return languageList.size();}}

step11:

package com.example.iosdialogdemo;import android.view.View;import android.widget.Button;import android.widget.TextView;import androidx.annotation.NonNull;import androidx.recyclerview.widget.RecyclerView;public class LanguageViewHolder extends RecyclerView.ViewHolder {TextView orderNumber;TextView language;Button btnDelete;public LanguageViewHolder(@NonNull View itemView) {super(itemView);orderNumber = itemView.findViewById(R.id.tvOrderNumber);language = itemView.findViewById(R.id.tvLanguage);btnDelete = itemView.findViewById(R.id.btnDelete);}
}

step12:

package com.example.iosdialogdemo;import androidx.appcompat.app.AppCompatActivity;import androidx.recyclerview.widget.LinearLayoutManager;import androidx.recyclerview.widget.RecyclerView;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.EditText;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity implements ILanguageRecycleListener {private LanguageRecycleAdapter languageRecycleAdapter;private RecyclerView rvLanguage;
//    private List<String> languageList = new ArrayList<>();private EditText editText;private Button btn_add,btn_update;private UserDao userDao;private DaoSession daoSession;private List<User> languageList;private Long id2;private String title2;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);daoSession = ((GreenApp) getApplication()).getDaoSession();userDao = daoSession.getUserDao();languageList = new ArrayList<>();if (languageList!=null){languageList.clear();}languageList.addAll(userDao.queryBuilder().list());rvLanguage = findViewById(R.id.rvLanguage);editText= findViewById(R.id.etLanguage);btn_add= findViewById(R.id.btn_add);btn_update= findViewById(R.id.btn_update);RecyclerView.LayoutManager layoutManager = newLinearLayoutManager(this);rvLanguage.setLayoutManager(layoutManager);languageRecycleAdapter = new LanguageRecycleAdapter(languageList, this);rvLanguage.setAdapter(languageRecycleAdapter);btn_add.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {String etString = editText.getText().toString();// languageList.add(etString);User user = new User();user.setName(etString);userDao.insert(user);if (languageList!=null){languageList.clear();}languageList.addAll(userDao.queryBuilder().list());languageRecycleAdapter.setData(languageList);languageRecycleAdapter.notifyDataSetChanged();}});btn_update.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {String etString = editText.getText().toString();// languageList.add(etString);Log.e("TAG", "sql_itemOnClick: " +id2+"==="+title2);User user = new User();user.setName(etString);user.setId(id2);userDao.update(user);if (languageList!=null){languageList.clear();}languageList.addAll(userDao.queryBuilder().list());languageRecycleAdapter.setData(languageList);languageRecycleAdapter.notifyDataSetChanged();}});}@Overridepublic void itemOnClick(int model,Long id, String title,int position) {Log.e("TAG", "itemOnClick: " + id + ", " + position);if (model==2){userDao.deleteByKey(id);if (languageList!=null){languageList.clear();}languageList.addAll(userDao.queryBuilder().list());Log.e("TAG", "sql_itemOnClick: " +languageList);languageRecycleAdapter.setData(languageList);languageRecycleAdapter.notifyDataSetChanged();/*  languageList.remove(position);languageRecycleAdapter.setData(languageList);languageRecycleAdapter.notifyDataSetChanged();*/}else if (model==1){editText.setText(title);id2 = id;title2=title;}}
}

step13:

package com.example.iosdialogdemo;import org.greenrobot.greendao.annotation.Entity;
import org.greenrobot.greendao.annotation.Id;
import org.greenrobot.greendao.annotation.Generated;/*** Created by rhodel on 8/15/2017.*/@Entity
public class User {@Id(autoincrement = true)private Long id;private String name;@Generated(hash = 873297011)public User(Long id, String name) {this.id = id;this.name = name;}@Generated(hash = 586692638)public User() {}public Long getId() {return this.id;}public void setId(Long id) {this.id = id;}public String getName() {return this.name;}public void setName(String name) {this.name = name;}
}

step14:

package com.example.iosdialogdemo;import android.database.Cursor;
import android.database.sqlite.SQLiteStatement;import org.greenrobot.greendao.AbstractDao;
import org.greenrobot.greendao.Property;
import org.greenrobot.greendao.internal.DaoConfig;
import org.greenrobot.greendao.database.Database;
import org.greenrobot.greendao.database.DatabaseStatement;// THIS CODE IS GENERATED BY greenDAO, DO NOT EDIT.
/** * DAO for table "USER".
*/
public class UserDao extends AbstractDao<User, Long> {public static final String TABLENAME = "USER";/*** Properties of entity User.<br/>* Can be used for QueryBuilder and for referencing column names.*/public static class Properties {public final static Property Id = new Property(0, Long.class, "id", true, "_id");public final static Property Name = new Property(1, String.class, "name", false, "NAME");}public UserDao(DaoConfig config) {super(config);}public UserDao(DaoConfig config, DaoSession daoSession) {super(config, daoSession);}/** Creates the underlying database table. */public static void createTable(Database db, boolean ifNotExists) {String constraint = ifNotExists? "IF NOT EXISTS ": "";db.execSQL("CREATE TABLE " + constraint + "\"USER\" (" + //"\"_id\" INTEGER PRIMARY KEY AUTOINCREMENT ," + // 0: id"\"NAME\" TEXT);"); // 1: name}/** Drops the underlying database table. */public static void dropTable(Database db, boolean ifExists) {String sql = "DROP TABLE " + (ifExists ? "IF EXISTS " : "") + "\"USER\"";db.execSQL(sql);}@Overrideprotected final void bindValues(DatabaseStatement stmt, User entity) {stmt.clearBindings();Long id = entity.getId();if (id != null) {stmt.bindLong(1, id);}String name = entity.getName();if (name != null) {stmt.bindString(2, name);}}@Overrideprotected final void bindValues(SQLiteStatement stmt, User entity) {stmt.clearBindings();Long id = entity.getId();if (id != null) {stmt.bindLong(1, id);}String name = entity.getName();if (name != null) {stmt.bindString(2, name);}}@Overridepublic Long readKey(Cursor cursor, int offset) {return cursor.isNull(offset + 0) ? null : cursor.getLong(offset + 0);}    @Overridepublic User readEntity(Cursor cursor, int offset) {User entity = new User( //cursor.isNull(offset + 0) ? null : cursor.getLong(offset + 0), // idcursor.isNull(offset + 1) ? null : cursor.getString(offset + 1) // name);return entity;}@Overridepublic void readEntity(Cursor cursor, User entity, int offset) {entity.setId(cursor.isNull(offset + 0) ? null : cursor.getLong(offset + 0));entity.setName(cursor.isNull(offset + 1) ? null : cursor.getString(offset + 1));}@Overrideprotected final Long updateKeyAfterInsert(User entity, long rowId) {entity.setId(rowId);return rowId;}@Overridepublic Long getKey(User entity) {if(entity != null) {return entity.getId();} else {return null;}}@Overridepublic boolean hasKey(User entity) {return entity.getId() != null;}@Overrideprotected final boolean isEntityUpdateable() {return true;}}

end

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