作业十

package com.example.demo01;

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

import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.text.TextUtils;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {
    private EditText etName, etPrice, etNumber;
    private ListView listView;
    private String name, price, number;
    private MyHelper myHelper;
    private SQLiteDatabase db;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main1111);
        myHelper = new MyHelper(this);
        init();
    }

    public void click(View v) {
        ContentValues values; // 创建ContentValues对象
        switch (v.getId()) {
        case R.id.button1:
            name = etPrice.getText().toString();
            price = etName.getText().toString();
            number = etNumber.getText().toString();
            db = myHelper.getWritableDatabase();
            values = new ContentValues();
            values.put("name", name); // 将数据添加到ContentValues对象
            values.put("price", price);
            values.put("number", number);
            db.insert("cart", null, values);
            db.close();
            Toast.makeText(this, "信息已添加", Toast.LENGTH_SHORT).show();
            break;
        case R.id.button2:
            Log.e("yanwenhua", "123");
            List<Commodity> list = new ArrayList();
            db = myHelper.getWritableDatabase();
            Cursor cursor = db
                    .query("cart", null, null, null, null, null, null);
            if (cursor.getCount() == 0) {
                Toast.makeText(this, "没有数据", Toast.LENGTH_SHORT).show();
            } else {
                while (cursor.moveToNext()) {
                    Commodity commodity = new Commodity();
                    int nameIndex = cursor.getColumnIndex("name");
                    int priceIndex = cursor.getColumnIndex("price");
                    int numberIndex = cursor.getColumnIndex("number");
                    String name = cursor.getString(nameIndex);
                    String price = cursor.getString(priceIndex);
                    String number = cursor.getString(numberIndex);
                    Log.e("yanwenhua",
                            "cursor.getCount();--" + cursor.getCount()
                                    + "name-" + name + "  " + price + "  "
                                    + number);
                    commodity.setName(name);
                    commodity.setPrice(price);
                    commodity.setNumber(number);
                    list.add(commodity);
                }
                MyBaseAdapter adapter = new MyBaseAdapter(MainActivity.this,
                        list);
                listView.setAdapter(adapter);
                adapter.notifyDataSetChanged();
            }
            cursor.close();
            db.close();
            break;
        case  R.id.button3:
            name = etPrice.getText().toString();
            price = etName.getText().toString();
            number = etNumber.getText().toString();
            db = myHelper.getWritableDatabase();
            values = new ContentValues();       // 要修改的数据
            values.put("number",number);
            values.put("price",price);
            db.update("cart", values, "name=?",
                    new String[]{name}); // 更新并得到行数
            db.close();
            Toast.makeText(this, "信息已修改", Toast.LENGTH_SHORT).show();
            break;
        case R.id.button4:
            db = myHelper.getWritableDatabase();
            db.delete("cart", null, null);
            List<Commodity> list2 = new ArrayList();
            MyBaseAdapter adapter = new MyBaseAdapter(MainActivity.this,list2);
            listView.setAdapter(adapter);
            adapter.notifyDataSetChanged();
            db.close();
            Toast.makeText(this, "信息已删除", Toast.LENGTH_SHORT).show();
            break;
        }
    }

    private void init() {
        setContentView(R.layout.activity_main1111);
        etName = (EditText) findViewById(R.id.editText2);
        etPrice = (EditText) findViewById(R.id.editText1);
        etNumber = (EditText) findViewById(R.id.editText3);
        listView = (ListView) findViewById(R.id.listView);
        Button add = (Button) findViewById(R.id.button1);
        Button query = (Button) findViewById(R.id.button2);
        Button update = (Button) findViewById(R.id.button3);
        Button delete = (Button) findViewById(R.id.button4);
    }

    class MyBaseAdapter extends BaseAdapter {
        private List<Commodity> list;
        private LayoutInflater layoutInflater;
        public MyBaseAdapter(Context context, List<Commodity> list){
            this.layoutInflater = LayoutInflater.from(context);
            this.list = list;
        }
        @Override
        public int getCount() {
            Log.e("yanwenhua","list.size()--"+list.size());
            return list.size();
        }

        @Override
        public Object getItem(int position) {
            return null;
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder viewHolder;
            if (convertView==null){
                convertView=layoutInflater.inflate(R.layout.list_item,null);
                viewHolder=new ViewHolder(convertView);
                convertView.setTag(viewHolder);
            }else {
                viewHolder=(ViewHolder) convertView.getTag();
            }
            Commodity commodity = list.get(position);
            viewHolder.tv_name.setText("商品名称:"+commodity.getName());
            viewHolder.tv_price.setText("商品价格:"+commodity.getPrice());
            viewHolder.tv_number.setText("商品数量:"+commodity.getNumber());
            Log.e("yanwenhua","cartBean.getName()-"+commodity.getName()+"  "+commodity.getPrice()+"  "+commodity.getNumber());
            return convertView;
        }
        class ViewHolder{
            TextView tv_name;
            TextView tv_price;
            TextView tv_number;
            public ViewHolder(View view){
                tv_name = (TextView) view.findViewById(R.id.textView1);
                tv_price = (TextView) view.findViewById(R.id.textView2);
                tv_number = (TextView) view.findViewById(R.id.textView3);
            }
        }

    }
}
package com.example.demo01;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class Commodity {

    private String name;
       private String price;
       private String number;

       public String getName() {
           return name;
       }

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

       public String getPrice() {
           return price;
       }

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

       public String getNumber() {
           return number;
       }

       public void setNumber(String number) {
           this.number = number;
       }
}
package com.example.demo01;

import android.support.v7.app.ActionBarActivity;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class MyHelper extends SQLiteOpenHelper {

    public MyHelper(Context context) {
        super(context, "shoppingcart.db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE cart(_id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR(20),  price VARCHAR(20), number VARCHAR(20))");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }
}
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#E6E6E6"
    android:orientation="vertical"
    android:padding="10dp">
    
   <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="15dp"
        android:background="@android:color/white"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="10dp"
            android:text="名称:"
            android:textColor="#000"
            android:textSize="20sp" />

        <EditText
            android:id="@+id/editText1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="5dp"
            android:background="@null"
            android:maxLines="1"
            android:padding="10dp" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="15dp"
        android:background="@android:color/white"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="10dp"
            android:text="价格:"
            android:textColor="#000"
            android:textSize="20sp" />

        <EditText
            android:id="@+id/editText2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="5dp"
            android:background="@null"
            android:maxLines="1"
            android:padding="10dp" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:background="@android:color/white"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="10dp"
            android:text="数量:"
            android:textColor="#000"
            android:textSize="20sp" />

        <EditText
            android:id="@+id/editText3"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="5dp"
            android:background="@null"
            android:maxLines="1"
            android:padding="10dp" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="click"
            android:text="添加" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="click"
            android:text="查询" />

        <Button
            android:id="@+id/button3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="click"
            android:text="修改" />

        <Button
            android:id="@+id/button4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="click"
            android:text="删除" />
    </LinearLayout>

    <ListView
        android:id="@+id/listView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#ffffff" >
    </ListView>
    
</LinearLayout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="10dp">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="15sp"/>
    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="3dp"
        android:textSize="15sp"/>
    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="3dp"
        android:textSize="15sp"/>

</LinearLayout>

原文地址:https://www.cnblogs.com/shenxiaoqi/p/11850123.html