OrmLite的简单学习（增删改查_两个表）

参考学习网址：

1.android OrmLite 入门 - ziqiang1的专栏 - CSDN博客 http://blog.csdn.net/ziqiang1/article/details/52121643
2.android OrmLite 实际应用 - ziqiang1的专栏 - CSDN博客 http://blog.csdn.net/ziqiang1/article/details/52131304
3.Android ORMLite 框架的入门用法 - Hongyang - CSDN博客 http://blog.csdn.net/lmj623565791/article/details/39121377
综合学习了这个帖子，大概了解了OrmLite的增删改查。

核心步骤：

1.下载需要的jar包：
OrmLite Releases - Lightweight Object Relational Mapping (ORM) http://ormlite.com/releases/
具体做法根据android OrmLite 入门 - ziqiang1的专栏 - CSDN博客 http://blog.csdn.net/ziqiang1/article/details/52121643

2.具体代码实现根据android OrmLite 实际应用 - ziqiang1的专栏 - CSDN博客 http://blog.csdn.net/ziqiang1/article/details/52131304

以下是我学习别人的贴纸之后的代码

1.布局：

<?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:gravity="center|top"    android:orientation="vertical">    <EditText        android:id="@+id/ed_text"        android:hint="请输入id"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginTop="15dp"/>    <TextView        android:id="@+id/tv_add_info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="增学生、班级"/>    <TextView        android:id="@+id/tv_delete_info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="删学生byId"/>    <TextView        android:id="@+id/tv_delete_info_class"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="删班级byId"/>    <TextView        android:id="@+id/tv_update_info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="改学生byId"/>    <TextView        android:id="@+id/tv_search_info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="查学生byId"/>    <TextView        android:id="@+id/tv_search_all_info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="24sp"        android:text="查所有学生、班级"/>    <ScrollView        android:layout_width="match_parent"        android:layout_height="wrap_content">        <TextView            android:id="@+id/tv_show_result"            android:layout_marginTop="15dp"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:textSize="21sp"            android:text="显示操作结果"/>    </ScrollView></LinearLayout>

2.BaseDao:

public abstract class BaseDao<T,ID> {    private DatabaseHelper helper;    public BaseDao(Context context){        helper = DatabaseHelper.getInstance( context);    }    public DatabaseHelper getHelper(){        return helper;    }    public abstract Dao<T,ID> getDao();    public int add(T t){        try {            return getDao().create( t);        }catch ( SQLException e){            e.printStackTrace();        }        return -1;    }    public int addList(List<T> list){        try {            return getDao().create( list);        }catch ( SQLException e){            e.printStackTrace();        }        return -1;    }    public List<T> getAll(){        List<T> list = new ArrayList<>();        try {            list = getDao().queryForAll();        }catch ( SQLException e){            e.printStackTrace();        }        return list;    }    public T get(ID id){        try {            return getDao().queryForId( id);        }catch ( SQLException e){            e.printStackTrace();        }        return null;    }    public int update(T t){        try {            return getDao().update( t);        }catch ( SQLException e){            e.printStackTrace();        }        return -1;    }    public int delete(ID id){        try {            return getDao().deleteById( id);        }catch ( SQLException e){            e.printStackTrace();        }        return -1;    }}

3.Classz:

@DatabaseTable( tableName = Classz.TABLE_NAME)public class Classz {    public final static String TABLE_NAME = "t_class";    @DatabaseField(id = true)    private String id;    @DatabaseField(unique = true, canBeNull =  false)    private String name;    @DatabaseField( defaultValue = "音乐楼")    private String address;    public String getId() {        return id;    }    public void setId(String id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getAddress() {        return address;    }    public void setAddress(String address) {        this.address = address;    }    @Override    public String toString() {        return "classz{ id =" + id +" name=" + name +",address=" + address  +"}\n";    }}

4.ClasszDao:

public class ClasszDao extends BaseDao<Classz,String>{    public ClasszDao(Context context) {        super(context);    }    @Override    public Dao<Classz, String> getDao() {        try {            return getHelper().getDao(Classz.class);        }catch ( SQLException e) {            e.printStackTrace();        }        return null;    }    /**     * 根据班级名称获取班级信息     * @param className     * @return     */    public Classz getClassz( String className){        try {            List<Classz> name = getDao().queryBuilder()                    .where().eq("name",className).query();            if( name != null && name.size() > 0){                return name.get( 0);            }        }catch ( SQLException e) {            e.printStackTrace();        }        return null;    }}

5.DatabaseHelper:

/** * 数据库和表的创建 */public class DatabaseHelper extends OrmLiteSqliteOpenHelper{    private static final String TABLE_NAME = "my_orm_db";    private static final int DB_VERSION = 1;    private static DatabaseHelper instance;    /**     * 获得数据库实例     * @param mContext     * @return     */    public static DatabaseHelper getInstance( Context mContext){        mContext = mContext.getApplicationContext();        if( instance == null ){            synchronized ( DatabaseHelper.class){                if( instance == null){                    instance = new DatabaseHelper( mContext);                }            }        }        return instance;    }    public DatabaseHelper(Context context){        super( context, TABLE_NAME, null, DB_VERSION);    }    @Override    public void onCreate(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource) {        Log.d("myorm","表开始新建");        try {            TableUtils.createTable( connectionSource, Student.class);            TableUtils.createTable( connectionSource, Classz.class);            Log.d("myorm","表创建成功");        }catch ( SQLException e){            Log.d("myorm","表创建失败");            e.printStackTrace();        }    }    @Override    public void onUpgrade(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource, int i, int i1) {        Log.d("myorm","更新表");//        try {//            // 删除旧的数据库表。//            TableUtils.dropTable(connectionSource, Classz.class, true);//            TableUtils.dropTable(connectionSource, Student.class, true);////            // 重新创建新版的数据库。//            onCreate(sqLiteDatabase, connectionSource);//        } catch (SQLException e) {//            e.printStackTrace();//        }    }}

6.Student:

/** * 每一个实体类对应一张表 * 注解说明: * * 1.@DatabaseTable * DatabaseTable是一个类注解，一般用在实体类的上面，被添加该注解的类会创建一张表, * 表名称默认为类名称的小写，我们也可以通过 tableName 来指定表名称 * * 2.@DatabaseField * DatabaseField是一个属性注解，使用在被添加DatabaseTable注解的类中的属性字段上， * 被添加该注解的类字段，在表中也会有一个相对应的表字段 * */@DatabaseTable(tableName = Student.TABLE_NAME)public class Student {    public static final String TABLE_NAME = "t_student";    @DatabaseField(generatedId = true)    private int id;    @DatabaseField(defaultValue = "玫玫")    private String name;    @DatabaseField( foreign = true, columnName = "ofClass", foreignAutoRefresh = true)    private Classz ofClass;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public Classz getOfClass() {        return ofClass;    }    public void setOfClass(Classz ofClass) {        this.ofClass = ofClass;    }    @Override    public String toString() {        return "student{ id =" + id +" name=" + name +",ofClass=" + ofClass +"}\n";    }}

7.StudentDao:

public class StudentDao extends BaseDao<Student, Integer>{    public StudentDao(Context context){        super( context);    }    @Override    public Dao<Student, Integer> getDao() {        try {            return getHelper().getDao( Student.class);        }catch ( SQLException e){            e.printStackTrace();        }        return null;    }}

8.HomeActivity:

public class HomeActivity extends AppCompatActivity {    @BindView(R.id.ed_text)    EditText edText;    @BindView(R.id.tv_add_info)    TextView tvAddInfo;    @BindView(R.id.tv_delete_info)    TextView tvDeleteInfo;    @BindView(R.id.tv_update_info)    TextView tvUpdateInfo;    @BindView(R.id.tv_search_info)    TextView tvSearchInfo;    @BindView(R.id.tv_show_result)    TextView tvShowResult;    @BindView(R.id.tv_search_all_info)    TextView tvSearchAllInfo;    @BindView(R.id.tv_delete_info_class)    TextView tvDeleteInfoClass;    private StudentDao studentDao;    private ClasszDao classzDao;    private int number = 1;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_home);        ButterKnife.bind(this);        studentDao = new StudentDao(HomeActivity.this);        classzDao = new ClasszDao(HomeActivity.this);    }    /**     * 向表里插入信息     */    public void addInfo() {        Classz classz = new Classz();        classz.setId(String.valueOf(number));        classz.setName("钢琴" + number + "班");        Student student = new Student();        student.setOfClass(classz);        student.setName("莉莉" + number);        student.setId(number);        int addStudent = studentDao.add(student);        int addClassz = classzDao.add(classz);        String str1 = addStudent > -1 ? "添加student成功" : "添加student失败";        String str2 = addClassz > -1 ? "添加classz成功" : "添加classz失败";        tvShowResult.setText(number + str1 + str2);        number++;    }    /**     * 按id来查找对象     */    public void queryById() {        String str = edText.getText().toString().trim();        if (TextUtils.isEmpty(str)) {            return;        }        try {            int i = Integer.parseInt(str);            Student student = studentDao.get(i);            if( student == null ){                tvShowResult.setText("无此对象");            }else{                tvShowResult.setText(student.toString());            }        } catch (SQLException e) {            e.printStackTrace();        }    }    /**     * 查询表中所有对象     */    public void queryAll() {        List<Student> studentAll = studentDao.getAll();        List<Classz> classzsAll = classzDao.getAll();        tvShowResult.setText( "student:" + studentAll.toString() + "\n---------" + "\n" + "classz:" + classzsAll.toString());    }    /**     * 更新学生对象信息     */    public void updateInfo() {        String str = edText.getText().toString().trim();        if (TextUtils.isEmpty(str)) {            return;        }        Student student = studentDao.get( Integer.parseInt(str));        if( student == null){            tvShowResult.setText("无此学生对象,转班失败");            return;        }        String studentOldInfo = student.toString();        Classz classz = classzDao.getClassz("钢琴1班");        if( classz == null){            tvShowResult.setText("无此班级对象,转班失败");            return;        }        student.setOfClass(classz);        int update = studentDao.update(student);        tvShowResult.setText( "studentOldInfo：" + studentOldInfo + "\n"                + ( update > -1 ? "转班成功" : "转班失败")  + "\n"                +  "studentNewInfo：" +  student.toString() );    }    /**     * 删除表中对象     */    public void deleteInfo() {        String str = edText.getText().toString().trim();        if (TextUtils.isEmpty(str)) {            return;        }        try {            int i = Integer.parseInt(str);            int result = studentDao.delete(i);            tvShowResult.setText(result > -1 ? "删除成功" : "删除失败");        } catch (SQLException e) {            e.printStackTrace();        }    }    /**     * 删除表中班级对象     */    public void deleteInfoClassz() {        String str = edText.getText().toString().trim();        if (TextUtils.isEmpty(str)) {            return;        }        try {            int result = classzDao.delete(str);            tvShowResult.setText(result > -1 ? "删除成功" : "删除失败");        } catch (SQLException e) {            e.printStackTrace();        }    }    @OnClick({R.id.tv_add_info, R.id.tv_delete_info, R.id.tv_update_info,            R.id.tv_search_info, R.id.tv_search_all_info, R.id.tv_delete_info_class})    public void onViewClicked(View view) {        switch (view.getId()) {            case R.id.tv_add_info:                addInfo();                break;            case R.id.tv_delete_info:                deleteInfo();//删除学生                break;            case R.id.tv_delete_info_class:                deleteInfoClassz();                break;            case R.id.tv_update_info:                updateInfo();                break;            case R.id.tv_search_info:                queryById();                break;            case R.id.tv_search_all_info:                queryAll();                break;        }    }}