Android_9购物车

  1 <?xml version="1.0" encoding="utf-8"?>
  2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  3     xmlns:tools="http://schemas.android.com/tools"
  4     android:layout_width="match_parent"
  5     android:layout_height="wrap_content"
  6     android:orientation="vertical"
  7     tools:context=".MainActivity">
  8 
  9     <TextView
 10         android:id="@+id/textView"
 11         android:layout_width="match_parent"
 12         android:layout_height="wrap_content"
 13         android:background="#FF5722"
 14         android:gravity="center_horizontal"
 15         android:text="购物车"
 16         android:textSize="24sp" />
 17 
 18     <TableLayout
 19         android:layout_width="match_parent"
 20         android:layout_height="match_parent">
 21 
 22         <TableRow
 23             android:layout_width="match_parent"
 24             android:layout_height="match_parent"
 25             android:gravity="center_horizontal">
 26 
 27             <TextView
 28                 android:id="@+id/textView2"
 29                 android:layout_width="wrap_content"
 30                 android:layout_height="wrap_content"
 31                 android:text="物品名：" />
 32 
 33             <EditText
 34                 android:id="@+id/et_1"
 35                 android:layout_width="wrap_content"
 36                 android:layout_height="wrap_content"
 37                 android:ems="10"
 38                 android:inputType="textPersonName" />
 39         </TableRow>
 40 
 41         <TableRow
 42             android:layout_width="match_parent"
 43             android:layout_height="match_parent"
 44             android:gravity="center_horizontal">
 45 
 46             <TextView
 47                 android:id="@+id/textView4"
 48                 android:layout_width="wrap_content"
 49                 android:layout_height="wrap_content"
 50                 android:text="价格：" />
 51 
 52             <EditText
 53                 android:id="@+id/et_2"
 54                 android:layout_width="match_parent"
 55                 android:layout_height="wrap_content"
 56                 android:ems="10"
 57                 android:inputType="textPersonName" />
 58         </TableRow>
 59 
 60         <TableRow
 61             android:layout_width="match_parent"
 62             android:layout_height="match_parent"
 63             android:gravity="center_horizontal">
 64 
 65             <TextView
 66                 android:id="@+id/textView5"
 67                 android:layout_width="wrap_content"
 68                 android:layout_height="wrap_content"
 69                 android:text="数量：" />
 70 
 71             <EditText
 72                 android:id="@+id/et_3"
 73                 android:layout_width="wrap_content"
 74                 android:layout_height="wrap_content"
 75                 android:ems="10"
 76                 android:inputType="textPersonName" />
 77 
 78         </TableRow>
 79 
 80     </TableLayout>
 81 
 82     <LinearLayout
 83         android:layout_width="match_parent"
 84         android:layout_height="match_parent"
 85         android:orientation="horizontal">
 86 
 87         <Button
 88             android:id="@+id/add"
 89             android:layout_width="match_parent"
 90             android:layout_height="match_parent"
 91             android:layout_weight="1"
 92             android:onClick="add_Click"
 93             android:text="加入购物车" />
 94 
 95         <Button
 96             android:id="@+id/delete"
 97             android:layout_width="match_parent"
 98             android:layout_height="match_parent"
 99             android:layout_weight="1"
100             android:onClick="delete_Click"
101             android:text="从购物车中删除" />
102 
103         <Button
104             android:id="@+id/query"
105             android:layout_width="match_parent"
106             android:layout_height="match_parent"
107             android:layout_weight="1"
108             android:onClick="find_Click"
109             android:text="查看购物车" />
110 
111         <Button
112             android:id="@+id/update"
113             android:layout_width="match_parent"
114             android:layout_height="match_parent"
115             android:layout_weight="1"
116             android:onClick="update_Click"
117             android:text="修改购物车中物品" />
118 
119     </LinearLayout>
120 
121     <LinearLayout
122         android:layout_width="match_parent"
123         android:layout_height="match_parent"
124         android:orientation="horizontal">
125 
126         <TextView
127             android:id="@+id/textView3"
128             android:layout_width="40dp"
129             android:layout_height="wrap_content"
130             android:layout_weight="1"
131             android:gravity="center_horizontal"
132             android:text="物品" />
133 
134         <TextView
135             android:id="@+id/textView6"
136             android:layout_width="40dp"
137             android:layout_height="wrap_content"
138             android:layout_weight="1"
139             android:gravity="center_horizontal"
140             android:text="价格" />
141 
142         <TextView
143             android:id="@+id/textView7"
144             android:layout_width="40dp"
145             android:layout_height="wrap_content"
146             android:layout_weight="1"
147             android:gravity="center_horizontal"
148             android:text="数量" />
149     </LinearLayout>
150 
151     <LinearLayout
152         android:layout_width="match_parent"
153         android:layout_height="match_parent"
154         android:orientation="vertical">
155 
156         <ListView
157             android:id="@+id/list"
158             android:layout_width="match_parent"
159             android:layout_height="match_parent"
160             android:layout_weight="1" />
161     </LinearLayout>
162 
163 </LinearLayout>

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent">
 5 
 6     <TextView
 7         android:id="@+id/t_name"
 8         android:layout_width="40dp"
 9         android:layout_height="30dp"
10         android:layout_weight="1"
11         android:background="@drawable/txt_shap"
12         android:gravity="left"
13         android:textSize="18sp"
14         android:textStyle="bold" />
15 
16     <TextView
17         android:id="@+id/t_price"
18         android:layout_width="40dp"
19         android:layout_height="30dp"
20         android:layout_weight="1"
21         android:background="@drawable/txt_shap"
22         android:gravity="right"
23         android:textSize="18sp" />
24 
25     <TextView
26         android:id="@+id/t_number"
27         android:layout_width="40dp"
28         android:layout_height="30dp"
29         android:layout_weight="1"
30         android:background="@drawable/txt_shap"
31         android:gravity="left"
32         android:textSize="18sp" />
33 
34 </LinearLayout>

 1  package com.example.myapplication;
 2 
 3 public class Sqldata {
 4 
 5     private int id;
 6     private String name,price,number;
 7 
 8     public Sqldata() {
 9     }
10 
11     public Sqldata(int id, String name, String price, String number) {
12         this.id = id;
13         this.name = name;
14         this.price = price;
15         this.number = number;
16     }
17 
18     public Sqldata(String name, String price, String number) {
19         this.name = name;
20         this.price = price;
21         this.number = number;
22     }
23 
24     public int getId() {
25         return id;
26     }
27 
28     public void setId(int id) {
29         this.id = id;
30     }
31 
32     public String getName() {
33         return name;
34     }
35 
36     public void setName(String name) {
37         this.name = name;
38     }
39 
40     public String getPrice() {
41         return price;
42     }
43 
44     public void setPrice(String price) {
45         this.price = price;
46     }
47 
48     public String getNumber() {
49         return number;
50     }
51 
52     public void setNumber(String number) {
53         this.number = number;
54     }
55 }

 1 package com.example.myapplication;
 2 
 3 import android.content.Context;
 4 import android.database.sqlite.SQLiteDatabase;
 5 import android.database.sqlite.SQLiteOpenHelper;
 6 
 7 import androidx.annotation.Nullable;
 8 
 9 public class MyHelper extends SQLiteOpenHelper {
10     public MyHelper(@Nullable Context context) {
11         super(context, "car.db", null, 1);
12     }
13 
14     @Override
15     public void onCreate(SQLiteDatabase db) {
16         db.execSQL("create table car(_id integer primary key autoincrement,name varchar(50),price varchar(50),number varchar(50))");
17     }
18 
19     @Override
20     public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
21 
22     }
23 }

  1 package com.example.myapplication;
  2 
  3 import androidx.annotation.NonNull;
  4 import androidx.appcompat.app.AppCompatActivity;
  5 
  6 import android.content.ContentValues;
  7 import android.content.Context;
  8 import android.content.Intent;
  9 import android.database.Cursor;
 10 import android.database.sqlite.SQLiteDatabase;
 11 import android.os.Bundle;
 12 import android.view.LayoutInflater;
 13 import android.view.View;
 14 import android.view.ViewGroup;
 15 import android.widget.ArrayAdapter;
 16 import android.widget.BaseAdapter;
 17 import android.widget.Button;
 18 import android.widget.EditText;
 19 import android.widget.ListView;
 20 import android.widget.TextView;
 21 import android.widget.Toast;
 22 
 23 import java.util.ArrayList;
 24 import java.util.List;
 25 
 26 public class MainActivity extends AppCompatActivity implements View.OnClickListener {
 27 
 28     Intent intent = new Intent();
 29     EditText name,price,number;
 30     Button add;
 31     ListView lv;
 32     private MyHelper helper;
 33     List<Sqldata> list = new ArrayList<>();
 34     @Override
 35     protected void onCreate(Bundle savedInstanceState) {
 36         super.onCreate(savedInstanceState);
 37         setContentView(R.layout.activity_main);
 38 
 39         name = (EditText)findViewById(R.id.et_1);
 40         price = (EditText)findViewById(R.id.et_2);
 41         number = (EditText)findViewById(R.id.et_3);
 42 
 43         add = (Button)findViewById(R.id.add);
 44 
 45         lv = (ListView)findViewById(R.id.list);
 46 
 47         helper = new MyHelper(this);
 48 
 49 
 50 
 51 
 52     }
 53 
 54 
 55     public void add_Click(View view){
 56         Sqldata date = new Sqldata(name.getText().toString(),price.getText().toString(),number.getText().toString());
 57         insert(date);
 58         Toast.makeText(MainActivity.this,name.getText().toString()+"已添加到购物车",Toast.LENGTH_SHORT).show();
 59     }
 60 
 61     public void delete_Click(View view){
 62         int num = delete(name.getText().toString());
 63         if (num > 0){
 64             Toast.makeText(MainActivity.this,"删除成功",Toast.LENGTH_SHORT).show();
 65         }else{
 66             Toast.makeText(MainActivity.this,"删除失败",Toast.LENGTH_SHORT).show();
 67         }
 68     }
 69 
 70 
 71 
 72 
 73     public void update_Click(View view){
 74         update(name.getText().toString(),price.getText().toString(),number.getText().toString());
 75     }
 76 
 77 
 78 
 79     public void find_Click(View view){
 80         find(name.getText().toString());
 81 
 82     }
 83 
 84 
 85 
 86     @Override
 87     public void onClick(View v) {
 88 
 89     }
 90 
 91 
 92 
 93 
 94     //添加到购物车
 95 
 96     public long insert(Sqldata sqldata){
 97         long id = 0;
 98         SQLiteDatabase db =null;
 99 
100         try {
101             db = helper.getWritableDatabase();
102 
103             ContentValues values = new ContentValues();
104 
105             values.put("name",sqldata.getName());
106             values.put("price",sqldata.getPrice());
107             values.put("number",sqldata.getNumber());
108 
109             db.insert("car",null,values);
110         } catch (Exception e) {
111             e.printStackTrace();
112         } finally {
113             if (db != null){
114                 db.close();
115             }
116         }
117 
118 
119         return id;
120     }
121 
122     //从购物车中删除
123 
124     public int delete(String name){
125 
126         SQLiteDatabase db = null;
127         int num = 0;
128         try {
129             db = helper.getWritableDatabase();
130             num = db.delete("car","name = ?",new String[]{name});
131         } catch (Exception e) {
132             e.printStackTrace();
133         } finally {
134             if (db!=null){
135                 db.close();
136             }
137         }
138         return num;
139     }
140 
141     //查看购物车
142 
143     public List<Sqldata> find(String name){
144         SQLiteDatabase db = null;
145         db = helper.getReadableDatabase();
146         MyBaseAdapter myBaseAdapter = new MyBaseAdapter(this,R.layout.item,list);
147         try {
148 
149                 Cursor cursor = db.query("car",null,null,null,null,null,null);
150                 if (cursor.getCount()!=0){
151                     while (cursor.moveToNext()){
152                         Sqldata find = new Sqldata();
153                         find.setName(cursor.getString(cursor.getColumnIndex("name")));
154                         find.setPrice(cursor.getString(cursor.getColumnIndex("price")));
155                         find.setNumber(cursor.getString(cursor.getColumnIndex("number")));
156                         list.add(find);
157                         lv.setAdapter(myBaseAdapter);
158                     }
159                 }
160                 cursor.close();
161 
162         } catch (Exception e) {
163             e.printStackTrace();
164         } finally {
165             if (db != null){
166                 db.close();
167             }
168         }
169 
170         return list;
171 
172     }
173 
174 
175     //对购物车进行修改
176 
177     public int update(String name,String price,String number){
178         SQLiteDatabase db = null;
179         int num = 0;
180         try {
181             db = helper.getWritableDatabase();
182             ContentValues values = new ContentValues();
183             values.put("price",price);
184             values.put("number",number);
185             num = db.update("car",values,"name = ?",new String[]{name});
186         } catch (Exception e) {
187             e.printStackTrace();
188         } finally {
189             if (db!=null){
190                 db.close();
191             }
192         }
193 
194         return num;
195     }
196 
197 
198 
199 
200 
201 
202 
203     class MyBaseAdapter extends BaseAdapter {
204 
205         public MyBaseAdapter(MainActivity mainActivity, int list_item, List<Sqldata> show) {
206         }
207 
208         @Override
209         public int getCount() {
210             return list.size();
211         }
212 
213         @Override
214         public Object getItem(int position) {
215             return null;
216         }
217 
218         @Override
219         public long getItemId(int position) {
220             return position;
221         }
222 
223         @Override
224         public View getView(int position, View convertView, ViewGroup parent) {
225             View view = View.inflate(MainActivity.this,R.layout.item,null);
226             TextView tname = (TextView)view.findViewById(R.id.t_name);
227             TextView tprice = (TextView)view.findViewById(R.id.t_price);
228             TextView tnumber = (TextView)view.findViewById(R.id.t_number);
229 
230 
231             tname.setText(list.get(position).getName());
232             tprice.setText(list.get(position).getPrice());
233             tnumber.setText(list.get(position).getNumber());
234             return view;
235         }
236     }
237 
238 
239 }

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:app="http://schemas.android.com/apk/res-auto"
 4     xmlns:tools="http://schemas.android.com/tools"
 5     android:layout_width="match_parent"
 6     android:layout_height="match_parent"
 7     tools:context=".SecondActivity">
 8 
 9     <TextView
10         android:id="@+id/tn"
11         android:layout_width="150dp"
12         android:layout_height="wrap_content" />
13 
14     <TextView
15         android:id="@+id/tp"
16         android:layout_width="100dp"
17         android:layout_height="wrap_content" />
18 
19     <TextView
20         android:id="@+id/tnu"
21         android:layout_width="wrap_content"
22         android:layout_height="wrap_content" />
23 </LinearLayout>