• ObjectBox 初探

    使用效果：感觉比MySqlite简单一些

    内容包含：增、删、查（改和增差不多，只要id是一样，就默认为修改）

    ObjectBox  添加数据

    ObjectBox  随机添加

    ObjectBox 模糊查询

    ObjectBox  匹配查询

    ObjectBox  查询全部

    ObjectBox  删除全部

    ObjectBox  分页查询

    其中代码里 ViewBinding 不懂的，可以查看：ViewBinding 初探-在Activity和Adapter中使用_thiscopy的博客-CSDN博客

    界面展示

    正文代码

    一、build.gradle配置： ObjectBox 相关

            1、项目 build.gradle

    1. // Top-level build file where you can add configuration options common to all sub-projects/modules.
    2. buildscript {
    3.     //ObjectBox 相关
    4.     ext.objectboxVersion = "3.2.1"
    5.     repositories {
    6.         google()
    7.         jcenter()
    8.         //ObjectBox 相关
    9.         mavenCentral()
    10.     }
    11.     dependencies {
    12.         classpath "com.android.tools.build:gradle:4.0.1"
    13.         //ObjectBox 相关
    14.         classpath("io.objectbox:objectbox-gradle-plugin:$objectboxVersion")
    15.     }
    16. }
    17.  
    18. allprojects {
    19.     repositories {
    20.         google()
    21.         jcenter()
    22.     }
    23. }
    24.  
    25. task clean(type: Delete) {
    26.     delete rootProject.buildDir
    27. }

            2、app build.gradle

    注意：apply plugin: "io.objectbox" 须要添加到 dependencies 后面

    1. apply plugin: 'com.android.application'
    2.  
    3. android {
    4.     compileSdkVersion 32
    5.     buildToolsVersion "32.0.0"
    6.  
    7.     defaultConfig {
    8.         applicationId "com.xolo.myobjectbox"
    9.         minSdkVersion 16
    10.         targetSdkVersion 32
    11.         versionCode 1
    12.         versionName "1.0"
    13.  
    14.         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    15.     }
    16.  
    17.     buildTypes {
    18.         release {
    19.             minifyEnabled false
    20.             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
    21.         }
    22.     }
    23.  
    24.     buildFeatures {
    25.         viewBinding = true
    26.     }
    27.  
    28.     compileOptions {
    29.         sourceCompatibility JavaVersion.VERSION_1_8
    30.         targetCompatibility JavaVersion.VERSION_1_8
    31.     }
    32. }
    33.  
    34. dependencies {
    35.     implementation fileTree(dir: "libs", include: ["*.jar"])
    36.     implementation 'androidx.appcompat:appcompat:1.3.1'
    37.     implementation 'androidx.constraintlayout:constraintlayout:2.1.1'
    38.     testImplementation 'junit:junit:4.12'
    39.     androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    40.     androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
    41.  
    42.     //ButterKnife
    43.     /*implementation 'com.jakewharton:butterknife:10.2.3'
    44.     annotationProcessor  'com.jakewharton:butterknife-compiler:10.2.3'*/
    45.  
    46.     //RecyclerView 列表
    47.     implementation 'androidx.recyclerview:recyclerview:1.2.0-beta01'
    48.  
    49.     //SmartRefreshLayout 下拉刷新 上拉加载
    50.     implementation 'com.scwang.smartrefresh:SmartRefreshLayout:1.0.4-7'
    51.     implementation 'com.scwang.smartrefresh:SmartRefreshHeader:1.0.4-7'
    52. }
    53.  
    54. //ObjectBox 相关
    55. apply plugin: "io.objectbox" // Add after other plugins.

    二、增、删、查相关代码

            1、activity_main.xml

    2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    3.     xmlns:app="http://schemas.android.com/apk/res-auto"
    4.     xmlns:tools="http://schemas.android.com/tools"
    5.     android:layout_width="match_parent"
    6.     android:layout_height="match_parent"
    7.     android:orientation="vertical"
    8.     tools:context=".MainActivity">
    9.  
    10.     <LinearLayout
    11.         android:layout_width="match_parent"
    12.         android:layout_height="wrap_content"
    13.         android:orientation="vertical">
    14.  
    15.         <EditText
    16.             android:id="@+id/etName"
    17.             android:layout_width="match_parent"
    18.             android:layout_height="wrap_content"
    19.             android:hint="名称"
    20.             android:textColor="#000000"
    21.             android:textSize="18sp" />
    22.  
    23.         <EditText
    24.             android:id="@+id/etAge"
    25.             android:layout_width="match_parent"
    26.             android:layout_height="wrap_content"
    27.             android:hint="年龄"
    28.             android:inputType="number"
    29.             android:textColor="#000000"
    30.             android:textSize="18sp" />
    31.  
    32.         <LinearLayout
    33.             android:layout_width="match_parent"
    34.             android:layout_height="wrap_content"
    35.             android:orientation="horizontal">
    36.  
    37.             <Button
    38.                 android:id="@+id/btnAdd"
    39.                 android:layout_width="0dp"
    40.                 android:layout_weight="1"
    41.                 android:layout_height="wrap_content"
    42.                 android:text="添加" />
    43.             <Button
    44.                 android:id="@+id/btnQuery"
    45.                 android:layout_width="0dp"
    46.                 android:layout_weight="1"
    47.                 android:layout_height="wrap_content"
    48.                 android:layout_marginLeft="5dp"
    49.                 android:text="查询" />
    50.  
    51.  
    52.         LinearLayout>
    53.  
    54.  
    55.     LinearLayout>
    56.  
    57.     <TextView
    58.         android:layout_width="match_parent"
    59.         android:layout_height="40dp"
    60.         android:background="#D9F8F5"
    61.         android:gravity="center|left"
    62.         android:paddingLeft="20dp"
    63.         android:text="数据列表-点击可删、下拉刷新、上拉加载"
    64.         android:textColor="#000000"
    65.         android:textSize="18sp" />
    66.  
    67.     <com.scwang.smartrefresh.layout.SmartRefreshLayout
    68.         android:id="@+id/srlControl"
    69.         android:layout_width="match_parent"
    70.         android:layout_height="0dp"
    71.         android:layout_weight="1"
    72.         app:srlAccentColor="#00000000"
    73.         app:srlEnablePreviewInEditMode="true"
    74.         app:srlPrimaryColor="#00000000">
    75.  
    76.         <com.scwang.smartrefresh.layout.header.ClassicsHeader
    77.             android:layout_width="match_parent"
    78.             android:layout_height="wrap_content" />
    79.  
    80.         <androidx.recyclerview.widget.RecyclerView
    81.             android:id="@+id/rvData"
    82.             android:layout_width="match_parent"
    83.             android:layout_height="match_parent" />
    84.  
    85.         <com.scwang.smartrefresh.layout.footer.ClassicsFooter
    86.             android:layout_width="match_parent"
    87.             android:layout_height="wrap_content" />
    88.  
    89.     com.scwang.smartrefresh.layout.SmartRefreshLayout>
    90.  
    91.     <LinearLayout
    92.         android:layout_width="match_parent"
    93.         android:layout_height="wrap_content"
    94.         android:orientation="horizontal">
    95.  
    96.         <Button
    97.             android:id="@+id/btnRandomFill"
    98.             android:layout_width="0dp"
    99.             android:layout_weight="1"
    100.             android:layout_height="wrap_content"
    101.             android:text="随机填充 100 条" />
    102.         <Button
    103.             android:id="@+id/btnDel"
    104.             android:layout_width="0dp"
    105.             android:layout_weight="1"
    106.             android:layout_height="wrap_content"
    107.             android:layout_marginLeft="5dp"
    108.             android:text="删除全部" />
    109.  
    110.  
    111.     LinearLayout>
    112.  
    113.  
    114. LinearLayout>

            2、MainActivity 

    1. import androidx.appcompat.app.AppCompatActivity;
    2. import androidx.recyclerview.widget.GridLayoutManager;
    3.  
    4. import android.os.Bundle;
    5. import android.widget.Toast;
    6.  
    7. import com.scwang.smartrefresh.layout.header.BezierRadarHeader;
    8. import com.xolo.myobjectbox.databinding.ActivityMainBinding;
    9.  
    10. import java.util.ArrayList;
    11. import java.util.List;
    12.  
    13. import io.objectbox.Box;
    14. import io.objectbox.query.Query;
    15. import io.objectbox.query.QueryBuilder;
    16.  
    17. public class MainActivity extends AppCompatActivity {
    18.  
    19.     //系统依据 activity_main.xml 自动生成的 ActivityMainBinding 类,通过 ActivityMainBinding 可以获取对应的控件
    20.     ActivityMainBinding mainBinding;
    21.  
    22.     private StudentAdapter studentAdapter;
    23.     private List list;
    24.  
    25.     @Override
    26.     protected void onCreate(Bundle savedInstanceState) {
    27.         super.onCreate(savedInstanceState);
    28.         //setContentView(R.layout.activity_main); -需要注释掉
    29.         //加载界面
    30.         mainBinding = ActivityMainBinding.inflate(getLayoutInflater());
    31.         setContentView(mainBinding.getRoot());
    32.  
    33.         //获取数据表对象
    34.         Box studentModelBox = MyObjectBoxApplication.getBoxStore().boxFor(StudentModel.class);
    35.  
    36.         //添加StudentAdapter适配器
    37.         list = new ArrayList<>();
    38.         studentAdapter = new StudentAdapter(this, list, o -> {
    39.             studentModelBox.remove(list.get((int)o));
    40.             list.remove((int)o);
    41.             studentAdapter.notifyDataSetChanged();
    42.             Toasts("删除成功");
    43.         });
    44.         mainBinding.rvData.setLayoutManager(new GridLayoutManager(this, 1));
    45.         mainBinding.rvData.setNestedScrollingEnabled(true);
    46.         mainBinding.rvData.setAdapter(studentAdapter);
    47.  
    48.         //添加点击事件
    49.         mainBinding.btnAdd.setOnClickListener(v -> {
    50.             String name = mainBinding.etName.getText().toString();
    51.             String age = mainBinding.etAge.getText().toString();
    52.             StudentModel studentModel = new StudentModel(name, age);
    53.             //添加进入数据库
    54.             studentModelBox.put(studentModel);
    55.             list.add(0, studentModel);
    56.             studentAdapter.notifyDataSetChanged();
    57.             Toasts("添加成功");
    58.             //清空输入框
    59.             mainBinding.etName.setText("");
    60.             mainBinding.etAge.setText("");
    61.         });
    62.  
    63.         //点击查询
    64.         mainBinding.btnQuery.setOnClickListener(v -> {
    65.             String name = mainBinding.etName.getText().toString();
    66.             String age = mainBinding.etAge.getText().toString();
    67.  
    68.             //模糊查询
    69.             list.clear();
    70.             Query query = studentModelBox.query()
    71.                     //匹配查询用 equal
    72.                     //.equal(StudentModel_.name, name, QueryBuilder.StringOrder.CASE_INSENSITIVE)
    73.                     //.equal(StudentModel_.age, age, QueryBuilder.StringOrder.CASE_INSENSITIVE)
    74.                     //模糊查询用 contains
    75.                     .contains(StudentModel_.name, name, QueryBuilder.StringOrder.CASE_INSENSITIVE)
    76.                     .contains(StudentModel_.age, age, QueryBuilder.StringOrder.CASE_INSENSITIVE)
    77.                     .build();
    78.             list.addAll(query.find(list.size(), 2));
    79.  
    80.             //查询全部数据
    81.             //list.addAll(studentModelBox.getAll());
    82.  
    83.             studentAdapter.notifyDataSetChanged();
    84.  
    85.             Toasts("查询成功");
    86.         });
    87.  
    88.         //删除全部
    89.         mainBinding.btnDel.setOnClickListener(v -> {
    90.             //清空界面
    91.             list.clear();
    92.             studentAdapter.notifyDataSetChanged();
    93.             //删除全部条码
    94.             studentModelBox.removeAll();
    95.         });
    96.  
    97.         //随机填充 100 条数据
    98.         mainBinding.btnRandomFill.setOnClickListener(v -> {
    99.             for(int i=0;i<100;i++){
    100.                 //添加进入数据库-随机生成姓名和年龄
    101.                 studentModelBox.put(new StudentModel(RandomWordUtils.randomWord(), String.valueOf((int)(Math.random()*100 + 1))));
    102.             }
    103.             Toasts("添加成功");
    104.         });
    105.  
    106.  
    107.         //下拉刷新
    108.         mainBinding.srlControl.setRefreshHeader(new BezierRadarHeader(getApplicationContext()).setEnableHorizontalDrag(true));
    109.         mainBinding.srlControl.setOnRefreshListener(refreshLayout -> {
    110.             //启用刷新动画
    111.             mainBinding.srlControl.setEnableRefresh(true);
    112.  
    113.             //查询第一条-从第 list.size() 条开始查，一次查10条，这里经过  list.clear() ，所以 list.size() 为 0
    114.             list.clear();
    115.             Query query = studentModelBox.query().build();
    116.             list.addAll(query.find(list.size(), 10));
    117.             studentAdapter.notifyDataSetChanged();
    118.  
    119.             //结束刷新动画
    120.             mainBinding.srlControl.finishRefresh();
    121.         });
    122.         //上拉加载
    123.         mainBinding.srlControl.setOnLoadmoreListener(refreshLayout -> {
    124.             //启用加载动画
    125.             mainBinding.srlControl.setEnableLoadmore(true);
    126.  
    127.             //分页查询-从第 list.size() 条开始查，一次查10条
    128.             Query query = studentModelBox.query().build();
    129.             list.addAll(query.find(list.size(), 10));
    130.             studentAdapter.notifyDataSetChanged();
    131.  
    132.             //结束加载动画
    133.             mainBinding.srlControl.finishLoadmore();
    134.         });
    135.  
    136.     }
    137.  
    138.     //Toast
    139.     public void Toasts(String content){
    140.         Toast.makeText(MyObjectBoxApplication.getMyObjectBoxApplication(), content, Toast.LENGTH_SHORT).show();
    141.     }
    142.  
    143. }

    三、adapter代码

            1、adapter_student.xml

    2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    3.     android:layout_width="match_parent"
    4.     android:layout_height="wrap_content"
    5.     android:orientation="vertical"
    6.     android:padding="5dp"
    7.     android:background="#FFFFFF"
    8.     android:layout_marginBottom="1dp"
    9.     android:id="@+id/llClick">
    10.  
    11.     <TextView
    12.         android:id="@+id/tvId"
    13.         android:layout_width="match_parent"
    14.         android:layout_height="wrap_content"
    15.         android:text="ID："
    16.         android:textColor="#000000"
    17.         android:textSize="18sp" />
    18.  
    19.     <TextView
    20.         android:id="@+id/tvName"
    21.         android:layout_width="match_parent"
    22.         android:layout_height="wrap_content"
    23.         android:text="name："
    24.         android:textColor="#000000"
    25.         android:textSize="18sp" />
    26.  
    27.     <TextView
    28.         android:id="@+id/tvAge"
    29.         android:layout_width="match_parent"
    30.         android:layout_height="wrap_content"
    31.         android:text="age："
    32.         android:textColor="#000000"
    33.         android:textSize="18sp" />
    34.  
    35.  
    36. LinearLayout>

            2、StudentAdapter

    1. import android.annotation.SuppressLint;
    2. import android.content.Context;
    3. import android.view.LayoutInflater;
    4. import android.view.ViewGroup;
    5.  
    6. import androidx.annotation.NonNull;
    7. import androidx.recyclerview.widget.RecyclerView;
    8.  
    9. import com.xolo.myobjectbox.databinding.AdapterStudentBinding;
    10.  
    11. import java.util.List;
    12.  
    13. public class StudentAdapter extends RecyclerView.Adapter.ViewHolder> {
    14.  
    15.     private Context context;
    16.     private List<StudentModel> list;
    17.     private ClickInterface clickInterface;
    18.  
    19.     public StudentAdapter(Context context, List<StudentModel> list, ClickInterface clickInterface) {
    20.         this.context = context;
    21.         this.list = list;
    22.         this.clickInterface = clickInterface;
    23.     }
    24.  
    25.     @NonNull
    26.     @Override
    27.     public StudentAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    28.         //界面设置
    29.         AdapterStudentBinding studentBinding = AdapterStudentBinding.inflate(LayoutInflater.from(context), parent, false);
    30.         return new ViewHolder(studentBinding);
    31.     }
    32.  
    33.     @SuppressLint("SetTextI18n")
    34.     @Override
    35.     public void onBindViewHolder(@NonNull StudentAdapter.ViewHolder holder, int position) {
    36.         holder.studentBinding.tvId.setText("ID："+list.get(position).getId());
    37.         holder.studentBinding.tvName.setText("姓名："+list.get(position).getName());
    38.         holder.studentBinding.tvAge.setText("年龄："+list.get(position).getAge());
    39.         holder.studentBinding.llClick.setOnClickListener(v -> clickInterface.ClickOnThe(position));
    40.     }
    41.  
    42.     @Override
    43.     public int getItemCount() {
    44.         return list.size();
    45.     }
    46.  
    47.     public class ViewHolder extends RecyclerView.ViewHolder {
    48.         系统依据 activity_main.xml 自动生成的 AdapterStudentBinding 类,通过 ActivityMainBinding 可以获取对应的控件
    49.         AdapterStudentBinding studentBinding;
    50.         public ViewHolder(@NonNull AdapterStudentBinding itemView) {
    51.             super(itemView.getRoot());
    52.             studentBinding = itemView;
    53.         }
    54.     }
    55. }

    四、RandomWordUtils 随机生成姓名代码

    1. //随机生成英文串串
    2. public class RandomWordUtils {
    3.  
    4.     public static String randomWord() {
    5.         int length = 12 + (int) (Math.random() * 9);
    6.         String word = "";
    7.         for (int i = 0; i < length; i++) {
    8.             word += (char) randomChar();
    9.         }
    10.         return word;
    11.     }
    12.  
    13.     private static byte randomChar() {
    14.         int flag = (int) (Math.random() * 2);// 0小写字母1大写字母
    15.         byte resultBt;
    16.         if (flag == 0) {
    17.             byte bt = (byte) (Math.random() * 26);// 0 <= bt < 26
    18.             resultBt = (byte) (65 + bt);
    19.         } else {
    20.             byte bt = (byte) (Math.random() * 26);// 0 <= bt < 26
    21.             resultBt = (byte) (97 + bt);
    22.         }
    23.         return resultBt;
    24.     }
    25. }

    五、StudentModel 代码

    注意事项：ObjectBox 需要创建任意一个 @Entity class 否则会一直提示找不到MyObjectBox
    需要rebuild project 项目，此时就可以在Application下使用MyObjectBox了

    1. import io.objectbox.annotation.Entity;
    2. import io.objectbox.annotation.Id;
    3.  
    4. //ObjectBox 需要创建任意一个 @Entity class 否则会一直提示找不到MyObjectBox
    5. //需要rebuild project 项目，此时就可以在Application下使用MyObjectBox了
    6. @Entity
    7. public class StudentModel {
    8.  
    9.     //@Id 也是 ObjectBox 必须添加的
    10.     @Id
    11.     private long id;
    12.     private String name;
    13.     private String age;
    14.  
    15.     public StudentModel() {
    16.     }
    17.  
    18.     public StudentModel(String name, String age) {
    19.         this.name = name;
    20.         this.age = age;
    21.     }
    22.  
    23.     public long getId() {
    24.         return id;
    25.     }
    26.  
    27.     public void setId(long id) {
    28.         this.id = id;
    29.     }
    30.  
    31.     public String getName() {
    32.         return name;
    33.     }
    34.  
    35.     public void setName(String name) {
    36.         this.name = name;
    37.     }
    38.  
    39.     public String getAge() {
    40.         return age;
    41.     }
    42.  
    43.     public void setAge(String age) {
    44.         this.age = age;
    45.     }
    46. }

    六、MyObjectBoxApplication 代码：需要在 AndroidManifest.xml 引入

    1. import android.app.Application;
    2. import android.util.Log;
    3.  
    4.  
    5. import io.objectbox.BoxStore;
    6. import io.objectbox.android.AndroidObjectBrowser;
    7.  
    8. public class MyObjectBoxApplication extends Application {
    9.  
    10.     private static BoxStore boxStore;
    11.     private static MyObjectBoxApplication myObjectBoxApplication;
    12.  
    13.     @Override
    14.     public void onCreate() {
    15.         super.onCreate();
    16.  
    17.         myObjectBoxApplication = this;
    18.  
    19.         //初始化 ObjectBox
    20.         boxStore = MyObjectBox.builder().androidContext(MyObjectBoxApplication.this).build();
    21.         if (BuildConfig.DEBUG) {
    22.             new AndroidObjectBrowser(boxStore).start(this);
    23.         }
    24.  
    25.         Log.d("App", "Using ObjectBox " + BoxStore.getVersion() + " (" + BoxStore.getVersionNative() + ")");
    26.     }
    27.  
    28.     public static MyObjectBoxApplication getMyObjectBoxApplication() {
    29.         return myObjectBoxApplication;
    30.     }
    31.  
    32.     public static BoxStore getBoxStore() {
    33.         return boxStore;
    34.     }
    35. }

    七、AndroidManifest.xml 代码

    2. <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    3.     package="com.xolo.myobjectbox">
    4.  
    5.     <application
    6.         android:name=".MyObjectBoxApplication"
    7.         android:allowBackup="true"
    8.         android:icon="@mipmap/ic_launcher"
    9.         android:label="@string/app_name"
    10.         android:roundIcon="@mipmap/ic_launcher_round"
    11.         android:supportsRtl="true"
    12.         android:theme="@style/AppTheme">
    13.         <activity android:name=".MainActivity">
    14.             <intent-filter>
    15.                 <action android:name="android.intent.action.MAIN" />
    16.  
    17.                 <category android:name="android.intent.category.LAUNCHER" />
    18.             intent-filter>
    19.         activity>
    20.     application>
    21.  
    22. manifest>

    八、ClickInterface 代码

    1. public interface ClickInterface {
    2.     void ClickOnThe(Object o);
    3. }

    九、代码界面展示

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  • 原文地址：https://blog.csdn.net/weixin_41454168/article/details/126320529