xutilsdb

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context=".MainActivity">    <Button        android:id="@+id/button_create"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="创建数据库"/>    <Button        android:id="@+id/button_insert"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="添加数据"/>    <Button        android:id="@+id/button_select"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="查询数据"/></LinearLayout>

public class MySqlite extends SQLiteOpenHelper {    public MySqlite(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {        super(context, name, factory, version);    }    public MySqlite(Context context, String name, SQLiteDatabase.CursorFactory factory, int version, DatabaseErrorHandler errorHandler) {        super(context, name, factory, version, errorHandler);    }    @Override    public void onCreate(SQLiteDatabase db) {        db.execSQL("create table uesr(id integer primary key autoincrement not null,name varchar(20),password varchar(20))");    }    @Override    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {    }}

@Table(name="user")public class User {    @Column(column = "id")//可以通过id查询    private String id;    private String name;    private String password;    public User(String id, String name, String password) {        this.id = id;        this.name = name;        this.password = password;    }    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 getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }}

public class MainActivity extends AppCompatActivity implements View.OnClickListener {    private Button mButtonCreate;    private Button mButtonInsert;    private Button mButtonSelect;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mButtonCreate= (Button) findViewById(R.id.button_create);        mButtonInsert= (Button) findViewById(R.id.button_insert);        mButtonSelect= (Button) findViewById(R.id.button_select);        mButtonCreate.setOnClickListener(this);        mButtonInsert.setOnClickListener(this);        mButtonSelect.setOnClickListener(this);    }    @Override    public void onClick(View view) {        switch (view.getId()){            case R.id.button_create:                MySqlite mysqlite=new MySqlite(getApplicationContext(),"sql_db",null,1);//"sql_db"数据库名称                mysqlite.getWritableDatabase();                Toast.makeText(MainActivity.this, "数据库以创建", Toast.LENGTH_SHORT).show();                break;            case R.id.button_insert:            //省略详情见Sqlite                break;            case R.id.button_select:                DbUtils dbutils=DbUtils.create(this,"sql_db");                try {                    List<User> users=dbutils.findAll(Selector.from(User.class));                    if (users==null){                        Toast.makeText(MainActivity.this, "没有任何数据", Toast.LENGTH_SHORT).show();                    }else {                        for (User user : users) {                            Log.d("TAG", "onClick " + user.getName() + user.getPassword());                        }                    }                } catch (DbException e) {                    e.printStackTrace();                }                break;            default:                break;        }    }}