Android 图书管理实现增删改查

Posted 2022-04-06 yangchas

目录结构如下：

java代码>>    
    Book.java
    BookActivity.java
    BookAdapter.java
    MainActivity.java
    MyDatabaseHelper.java
    UpdateBookActivity.java
layout>>
    activity_book.xml
    activity_main.xml
    activity_update_book.xml
    book_item.xml

 

Book.java

package com.example.p229;

import java.io.Serializable;


public class Book implements Serializable
        private int id;
        private String author;
        private double price;
        private int pages;
        private String name;

    public Book(int id, String author, double price, int pages, String name) 
        super();
        this.id = id;
        this.author = author;
        this.price=price;
        this.pages = pages;
        this.name = name;
    
    public Book(String author, double price, int pages, String name) 
        super();
        this.author = author;
        this.price=price;
        this.pages = pages;
        this.name = name;
    

    public Book() 
        super();
    

    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 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 double getPrice() 
        return price;
    
    public void setPrice(double price) 
        this.price = price;
    

BookActivity

package com.example.p229;

import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.preference.DialogPreference;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.ButtonBarLayout;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class BookActivity extends AppCompatActivity 
    private List<Book> bookList = new ArrayList<>();
    private ListView lv_book;
    private MyDatabaseHelper dbhelper;
    private Button data_clear;
    private BookAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_book);
        dbhelper = new MyDatabaseHelper(this, "BookStore.db", null, 1);
        //给数据源赋值
        initBooks();
        //创建适配器

        //获取列表并设置适配器
        lv_book = (ListView) findViewById(R.id.lv_book);
        if (adapter == null) 
            adapter = new BookAdapter(BookActivity.this, R.layout.book_item, bookList);
            lv_book.setAdapter(adapter);

         else 
            adapter.notifyDataSetChanged();
        
        //短时间选中该书触发的事件———弹出修改对话框
        lv_book.setOnItemClickListener(new AdapterView.OnItemClickListener() 
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) 
                Book book = bookList.get(position);
                showBookInfoDialog(book);
                // Toast.makeText(BookActivity.this,book.getName(),Toast.LENGTH_SHORT).show();
            
        );
        //长时间选中该书触发的事件———弹出删除对话框
        lv_book.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() 
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) 
                Book book = bookList.get(position);
                //Toast.makeText(BookActivity.this,book.getName(),Toast.LENGTH_SHORT).show();
                showDeleteInfoDialog(book);
                return false;
            
        );
        data_clear = (Button) findViewById(R.id.data_clear);
        data_clear.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                clear();
            
        );


    

    @Override
    protected void onResume() 
        super.onResume();
        initBooks();
    

    protected void showBookInfoDialog(final Book book) 
        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
        dialog.setIcon(R.mipmap.ic_launcher);
        dialog.setTitle("图书信息");
        dialog.setMessage(""
                + "id:" + book.getId()
                + "\n作者:" + book.getAuthor()
                + "\n单价:" + book.getPrice()
                + "\n页数:" + book.getPages()
                + "\n书名:" + book.getName()
        );

        dialog.setPositiveButton("修改", new DialogInterface.OnClickListener() 

            @Override
            public void onClick(DialogInterface dialog, int which) 
            //由当前活动跳转到UpdateBookActivity活动，病传递数据book
                Intent intent=new Intent(BookActivity.this,UpdateBookActivity.class);
                intent.putExtra("book",book);
                startActivity(intent);
            
        );
        dialog.setNegativeButton("取消", null);
        dialog.show();
    



    protected void showDeleteInfoDialog(final Book book) 
        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
        dialog.setIcon(R.mipmap.ic_launcher);
        dialog.setTitle("提示信息");
        dialog.setMessage("请问您要删除这条数据吗");
        dialog.setPositiveButton("确认", new DialogInterface.OnClickListener() 
            @Override
            public void onClick(DialogInterface dialog, int which) 
               //删除图书，首先从数据课表中删除，其次从集合中删除，目的就是让lv能同步显示删除后的状态或结果
                SQLiteDatabase db=dbhelper.getWritableDatabase();
                int count=db.delete("Book","id=?",new String[]book.getId()+"");
                if(count!=0)
                    Toast.makeText(BookActivity.this, "数据库中删除成功！！", Toast.LENGTH_SHORT).show();
                    bookList.remove(book);
                    adapter.notifyDataSetChanged();
                
                else
                    Toast.makeText(BookActivity.this, "没有删除！！", Toast.LENGTH_SHORT).show();

                
                db.close();
            
        );
        dialog.setNegativeButton("取消", null);
        dialog.show();
    

    public void clear() 
        SQLiteDatabase db = dbhelper.getWritableDatabase();
        int count = db.delete("Book", null, null);
        if (count!= 0) 
            Toast.makeText(this, "数据库表删除成功！！", Toast.LENGTH_SHORT).show();
            bookList.clear();
            adapter.notifyDataSetChanged();
         else 
            Toast.makeText(this, "没有内容可以删除！！", Toast.LENGTH_SHORT).show();

        
        db.close();
    

    private void initBooks() 
        SQLiteDatabase db = dbhelper.getWritableDatabase();
        bookList.clear();

        //给数据源赋值
        Cursor cursor = db.query("Book", null, null, null, null, null, null);
        //2.进行遍历
        if (cursor.moveToFirst()) 
            do 
//                String name=cursor.getString(cursor.getColumnIndex("name"));
//                String author=cursor.getString(cursor.getColumnIndex("author"));
//                int pages=cursor.getInt(cursor.getColumnIndex("pages"));
//               int id=cursor.getInt(cursor.getColumnIndex("id"));
//                double price=cursor.getDouble(cursor.getColumnIndex("price"));
                //id列的索引号为0
                int id = cursor.getInt(0);
                String author = cursor.getString(cursor.getColumnIndex("author"));
                double price = cursor.getDouble(cursor.getColumnIndex("price"));
                int pages = cursor.getInt(cursor.getColumnIndex("pages"));
                String name = cursor.getString(cursor.getColumnIndex("name"));
                //Book book=new Book(id,author,price,pages,name);
                Book book = new Book();
                book.setId(id);
                book.setName(name);
                book.setPages(pages);
                book.setPrice(price);
                book.setAuthor(author);


                bookList.add(book);

             while (cursor.moveToNext());
        
        // 3.关闭游标
        cursor.close();
        db.close();
    

BookAdapter

package com.example.p229;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.List;

public class BookAdapter extends ArrayAdapter<Book> 
    private int resourceId;

    public BookAdapter(Context context, int resource, List<Book> objects) 
        super(context, resource, objects);
        resourceId = resource;
    


    @Override
    public View getView(int position, View convertView, ViewGroup parent) 
        Book book = getItem(position);
        View view;
        ViewHolder viewHolder;
        if (convertView == null) 
            //是否有布局缓存，否
            view = LayoutInflater.from(getContext()).inflate(resourceId, parent, false);
            //创建viewHolder
            viewHolder = new ViewHolder();
            //获取ViewHolder的控件
            viewHolder.bookId = (TextView) view.findViewById(R.id.book_id);
            viewHolder.bookAuthor = (TextView) view.findViewById(R.id.book_author);
            viewHolder.bookPrice = (TextView) view.findViewById(R.id.book_price);
            viewHolder.bookPages = (TextView) view.findViewById(R.id.book_pages);
            viewHolder.bookName = (TextView) view.findViewById(R.id.book_name);
            //将viewHolder对象存储view中
            view.setTag(viewHolder);
         else 
//有缓存
            view = convertView;
            viewHolder = (ViewHolder) view.getTag();
        
        viewHolder.bookId.setText(book.getId() + "");
        viewHolder.bookAuthor.setText(book.getAuthor() + "");
        viewHolder.bookPrice.setText(book.getPrice() + "");
        viewHolder.bookPages.setText(book.getPages() + "");
        viewHolder.bookName.setText(book.getName() + "");

        //fruitImage.setImageResource(fruit.getImageId());
        // fruitname.setText(fruit.getName());
        return view;


    

    class ViewHolder 
        TextView bookId;
        TextView bookAuthor;
        TextView bookPrice;
        TextView bookPages;
        TextView bookName;
    

MainActivity

package com.example.p229;

import android.content.ContentValues;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener 
    private EditText author_et;
    private EditText price_et;
    private EditText pages_et;
    private EditText name_et;
    private Button insert_data;
    private Button query_data;
    private MyDatabaseHelper dbhelper;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        dbhelper = new MyDatabaseHelper(this, "BookStore.db", null, 1);
        dbhelper.getWritableDatabase();
        author_et = (EditText) findViewById(R.id.author_et);
        price_et = (EditText) findViewById(R.id.price_et);
        pages_et = (EditText) findViewById(R.id.pages_et);
        name_et = (EditText) findViewById(R.id.name_et);

        insert_data = (Button) findViewById(R.id.add_data);
        insert_data.setOnClickListener(this);
        query_data = (Button) findViewById(R.id.query_data);
        query_data.setOnClickListener(this);
    


    @Override
    public void onClick(View v) 
        switch (v.getId()) 
            case R.id.add_data:
                insertData();
                break;
            case R.id.query_data:
                Intent intent = new Intent(MainActivity.this, BookActivity.class);
                startActivity(intent);
                break;
        
    

    private void insertData() 
        SQLiteDatabase db = dbhelper.getWritableDatabase();
        ContentValues values = new ContentValues();
        String author = author_et.getText().toString();
        String name = name_et.getText().toString();
        String price = price_et.getText().toString();
        String pages = pages_et.getText().toString();
        values.put("name", name);
        values.put("author", author);
        values.put("price", Double.parseDouble(price));
        values.put("pages", Integer.parseInt(pages));
        long count = db.insert("Book", null, values);
        if (count != -1) 
            Toast.makeText(this, "插入成功！！", Toast.LENGTH_SHORT).show();
            author_et.setText("");
            name_et.setText("");
            price_et.setText("");
            pages_et.setText("");
         else 
            Toast.makeText(this, "插入失败！！", Toast.LENGTH_SHORT).show();

        
        db.close();
    

MyDatabaseHelper

package com.example.p229;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

/**
 * Created by user on 2019/4/27.
 */

public class MyDatabaseHelper extends SQLiteOpenHelper 
    public static final String CREATE_BOOK="create table Book("
            +"id integer primary key autoincrement,"
            + "author text,"
            + "price real,"
            + "pages integer,"
            +"name text)";

    private Context mContext;

    public MyDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) 
        super(context, name, factory, version);
        mContext=context;
    

    @Override
    public void onCreate(SQLiteDatabase db) 
        db.execSQL(CREATE_BOOK);

        Toast.makeText(mContext,"成功建表！！",Toast.LENGTH_SHORT).show();
    

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) 

    

UpdateBookActivity

package com.example.p229;

import android.content.ContentValues;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class UpdateBookActivity extends AppCompatActivity 
    private EditText update_author_et;
    private EditText update_price_et;
    private EditText update_pages_et;
    private EditText update_name_et;
    private MyDatabaseHelper dbhelper;
    private Book book;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_update_book);
        //第一步：获取上一个活动传递过来的序列化book
        Intent intent=getIntent();
        book=(Book)intent.getSerializableExtra("book");
        //第二步：获取控件并显示数据
        update_author_et=(EditText) findViewById(R.id.update_author_et);
        update_price_et=(EditText) findViewById(R.id.update_price_et);
        update_pages_et=(EditText) findViewById(R.id.update_pages_et);
        update_name_et=(EditText) findViewById(R.id.update_name_et);

        update_author_et.setText(book.getAuthor());
        update_price_et.setText(book.getPrice()+"");
        update_pages_et.setText(book.getPages()+"");
        update_name_et.setText(book.getName());


        dbhelper=new MyDatabaseHelper(this,"BookStore.db",null,1);
    
    //按照页面上重新输入的信息去库中修改该书
    public void updateInfo(View view)
        //获取重新输入的信息
        String authorStr=update_author_et.getText().toString();
        String nameStr=update_name_et.getText().toString();
        String priceStr=update_price_et.getText().toString();
        String pagesStr=update_pages_et.getText().toString();
        //按照获取的信息是否合法决定进行的操作
        if(TextUtils.isEmpty(authorStr)||TextUtils.isEmpty(nameStr)
                ||TextUtils.isEmpty(pagesStr)||TextUtils.isEmpty(priceStr))
            Toast.makeText(this, "数据不完整，重新输入！", Toast.LENGTH_SHORT).show();

        
        else 
            //打开数据库
            SQLiteDatabase db=dbhelper.getWritableDatabase();
            ContentValues values=new ContentValues();
            values.put("name",nameStr);
            values.put("author",authorStr);
            values.put("pages",Integer.parseInt(pagesStr));
            values.put("price",Double.parseDouble(priceStr));
            int count=db.update("Book",values,"id=?",new String[]book.getId()+"");
            if(count!=0)
                Toast.makeText(this, "修改成功！！", Toast.LENGTH_SHORT).show();
                finish();
            
            else
                Toast.makeText(this, "修改失败！！", Toast.LENGTH_SHORT).show();

            
            db.close();

        
    
    //关闭页面
    public void cancel(View view)
        finish();
    

activity_book.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
<Button
    android:id="@+id/data_clear"
    android:text="清空"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:text="id"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" />

        <TextView
            android:text="name"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" />
        <TextView
            android:text="price"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" />
        <TextView
            android:text="author"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" />
        <TextView
            android:text="pages"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" />
    </LinearLayout>
    <ListView
        android:id="@+id/lv_book"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"></ListView>
</LinearLayout>

activity_main.xml

<?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:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.example.p229.MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="作者"
            android:textSize="18dp" />

        <EditText
            android:id="@+id/author_et"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="4"
            android:hint="输入作者" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="单价"
            android:textSize="18dp" />

        <EditText
            android:id="@+id/price_et"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="4"
            android:hint="输入单价" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="页数"
            android:textSize="18dp" />

        <EditText
            android:id="@+id/pages_et"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="4"
            android:hint="输入页数" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <TextView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="书名"
            android:textSize="18dp" />

        <EditText
            android:id="@+id/name_et"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="4"
            android:hint="输入书名" />
    </LinearLayout>

    <Button
        android:id="@+id/add_data"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="添加记录" />


    <Button
        android:id="@+id/query_data"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="显示数据库信息" />

</LinearLayout>

activity_update_book.xml

<?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:id="@+id/activity_update_book"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
   android:orientation="vertical"
    tools:context="com.example.p229.UpdateBookActivity">
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:text="作者"
            android:textSize="18dp"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content" />
        <EditText
            android:id="@+id/update_author_et"
            android:layout_width="0dp"
            android:layout_weight="4"
            android:layout_height="wrap_content"
            />
    </LinearLayout>

    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:text="单价"
            android:textSize="18dp"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content" />
        <EditText
            android:id="@+id/update_price_et"
            android:layout_width="0dp"
            android:layout_weight="4"
            android:layout_height="wrap_content"
            />
    </LinearLayout>
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:text="页数"
            android:textSize="18dp"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content" />
        <EditText
            android:id="@+id/update_pages_et"
            android:layout_width="0dp"
            android:layout_weight="4"
            android:layout_height="wrap_content"
           />
    </LinearLayout>
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:text="书名"
            android:textSize="18dp"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content" />
        <EditText
            android:id="@+id/update_name_et"
            android:layout_width="0dp"
            android:layout_weight="4"
            android:layout_height="wrap_content"
            />
    </LinearLayout>

    <Button
       android:onClick="updateInfo"
        android:textSize="18sp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="修改" />
    <Button
        android:onClick="cancel"
        android:textSize="18sp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="取消" />
</LinearLayout>

book_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
<TextView
    android:id="@+id/book_id"
    android:layout_weight="1"
    android:layout_width="0dp"
    android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/book_name"
        android:layout_weight="1"
        android:layout_width="0dp"
        android:layout_height="wrap_content" />
    <TextView
        android:id="@+id/book_price"
        android:layout_weight="1"
        android:layout_width="0dp"
        android:layout_height="wrap_content" />
    <TextView
        android:id="@+id/book_author"
        android:layout_weight="1"
        android:layout_width="0dp"
        android:layout_height="wrap_content" />
    <TextView
        android:id="@+id/book_pages"
        android:layout_weight="1"
        android:layout_width="0dp"
        android:layout_height="wrap_content" />
</LinearLayout>

完！