LitePal操作数据库

  compile 'org.litepal.android:core:1.5.0'

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:gravity="center_vertical"
    android:orientation="vertical"
    tools:context="com.example.litepaltest.MainActivity">

    <Button
        android:id="@+id/create_database"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center_vertical"
        android:text="创建数据库"

        />


    <Button
        android:id="@+id/add_data"

        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"

        android:gravity="center_vertical"

        android:text="添加数据"
        />

    <Button
        android:id="@+id/update_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center_vertical"
        android:text="修改数据"
        />


    <Button
        android:id="@+id/delete_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center_vertical"
        android:text="删除数据"
        />



    <Button
        android:id="@+id/query_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center_vertical"
        android:text="查询数据"
        />


</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<litepal>
    <dbname value="BookStore"></dbname>
    <version value="3" />

    <list>
        <mapping class="com.example.litepaltest.Book"></mapping>
        <mapping class="com.example.litepaltest.Category"></mapping>
    </list>

</litepal>

package com.example.litepaltest;

import org.litepal.crud.DataSupport;

/**
 * Created by Administrator on 2018/11/27 0027.
 */

public class Book extends DataSupport{

    private  int id;
    private String author;
    private  double price;
    private int pages;
    private String name;
    private String press;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public int getPages() {
        return pages;
    }

    public void setPages(int pages) {
        this.pages = pages;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPress() {
        return press;
    }

    public void setPress(String press) {
        this.press = press;
    }

    @Override
    public String toString() {
        return "Book{" +
                "id=" + id +
                ", author='" + author + '\'' +
                ", price=" + price +
                ", pages=" + pages +
                ", name='" + name + '\'' +
                ", press='" + press + '\'' +
                '}';
    }
}

package com.example.litepaltest;

/**
 * Created by Administrator on 2018/11/27 0027.
 */

public class Category {
    private int id;

    private String categoryName;

    private int categoryCode;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getCategoryName() {
        return categoryName;
    }

    public void setCategoryName(String categoryName) {
        this.categoryName = categoryName;
    }

    public int getCategoryCode() {
        return categoryCode;
    }

    public void setCategoryCode(int categoryCode) {
        this.categoryCode = categoryCode;
    }

    @Override
    public String toString() {
        return "Category{" +
                "id=" + id +
                ", categoryName='" + categoryName + '\'' +
                ", categoryCode=" + categoryCode +
                '}';
    }
}

package com.example.litepaltest;

import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import org.litepal.crud.DataSupport;
import org.litepal.tablemanager.Connector;

import java.util.List;

public class MainActivity extends AppCompatActivity {
    private static final String TAG = "MainActivity";

    private Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = getBaseContext();
        Button button = (Button) findViewById(R.id.create_database);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Toast.makeText(context, "建表成功", Toast.LENGTH_LONG).show();
                Connector.getDatabase();
            }
        });

        //添加
        Button addData = (Button) findViewById(R.id.add_data);
        addData.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Book book = new Book();
                book.setName("llop");
                book.setAuthor("fgdf");
                book.setPages(454);
                book.setPrice(15);
                book.setPress("unknow");
                book.save();
                Toast.makeText(context, "创建数据成功", Toast.LENGTH_LONG).show();
            }
        });


        //修改
        Button updData = (Button) findViewById(R.id.update_data);
        updData.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Book book = new Book();
                book.setName("gfgdg");
                book.setAuthor("kkjkj");
                book.setToDefault("pages");
                book.setPrice(2224);
                book.updateAll("name=? and author=?", "theTom", "ddd");
                book.save();
                Toast.makeText(context, "修改数据成功", Toast.LENGTH_LONG).show();
            }
        });

        //删除
        Button delData = (Button) findViewById(R.id.delete_data);
        delData.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                DataSupport.deleteAll(Book.class, "price<?", "15");
                Toast.makeText(context, "删除数据成功", Toast.LENGTH_LONG).show();
            }
        });

        //查询
        Button queryData = (Button) findViewById(R.id.query_data);
        queryData.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                List<Book> books = DataSupport.findAll(Book.class);
                for (Book book : books) {
                    Log.d(TAG, book.toString());
                }

                List<Book> books1 = DataSupport.order("price asc").find(Book.class);
                for (Book book : books1) {
                    Log.d(TAG, book.toString());
                }

                List<Book> books2 = DataSupport.limit(3).offset(1).find(Book.class);
                List<Book> books3 = DataSupport.select("name", "author", "price")
                        .where("pages > ?", "40")
                        .order("pages asc")
                        .limit(4)
                        .offset(1)
                        .find(Book.class);

                Toast.makeText(context, "查询数据成功", Toast.LENGTH_LONG).show();
            }
        });

    }
}