<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@mipmap/ab"
android:gravity="center"
android:orientation="vertical"
tools:context=".MainActivity">
<TextView
android:id="@+id/textView"
android:layout_width="match_parent"
android:layout_height="50dp"
android:background="#F85CDFDB"
android:gravity="center"
android:text="学生注册页"
android:textSize="30sp"
android:textStyle="bold" />
<TableLayout
android:layout_width="match_parent"
android:layout_height="200dp"
android:gravity="center">
<TableRow
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="姓名："
android:textSize="20sp"
android:textStyle="bold" />
<EditText
android:id="@+id/e_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPersonName" />
</TableRow>
<TableRow
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="年龄："
android:textSize="20sp"
android:textStyle="bold" />
<EditText
android:id="@+id/e_age"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPersonName" />
</TableRow>
</TableLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:orientation="horizontal">
<Button
android:id="@+id/btn_1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="增加"
app:backgroundTint="#EB5CDFDB" />
<Button
android:id="@+id/btn_2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="删除"
app:backgroundTint="#EB5CDFDB" />
<Button
android:id="@+id/btn_3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="修改"
app:backgroundTint="#EB5CDFDB" />
<Button
android:id="@+id/btn_4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="查找"
app:backgroundTint="#EB5CDFDB" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ListView
android:id="@+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</LinearLayout>
<?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/textView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
<TextView
android:id="@+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
<TextView
android:id="@+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
</LinearLayout>
1 package com.example.myapplication;
2
3 import android.content.Context;
4 import android.database.sqlite.SQLiteDatabase;
5 import android.database.sqlite.SQLiteOpenHelper;
6 import android.view.View;
7 import android.view.ViewGroup;
8 import android.widget.BaseAdapter;
9 import android.widget.TextView;
10
11 import androidx.annotation.Nullable;
12
13 public class Student extends SQLiteOpenHelper {
14 private int Id;
15 private String Name,Age;
16
17
18 public Student(@Nullable Context context) {
19 super(context, "student.db", null, 1);
20 }
21
22
23 @Override
24 public void onCreate(SQLiteDatabase db) {
25 db.execSQL("CREATE TABLE stu(_id INTEGER PRIMARY KEY AUTOINCREMENT,s_name VARCHAR(20),s_age INTEGER)");
26
27 }
28
29 @Override
30 public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
31
32 }
33
34
35 public String getName() {
36 return Name;
37 }
38
39 public void setName(String name) {
40 Name = name;
41 }
42
43 public String getAge() {
44 return Age;
45 }
46
47 public void setAge(String age) {
48 Age = age;
49 }
50
51 public int getId() {
52 return Id;
53 }
54
55 public void setId(int id) {
56 Id = id;
57 }
58 }
package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
Student helper = new Student(this);
private EditText e_name,e_age;
private Button btn_1,btn_2,btn_3,btn_4;
List<Student> show = new ArrayList<Student>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
e_name = (EditText)findViewById(R.id.e_name);
e_age = (EditText)findViewById(R.id.e_age);
btn_1 = (Button)findViewById(R.id.btn_1);
btn_2 = (Button)findViewById(R.id.btn_2);
btn_3 = (Button)findViewById(R.id.btn_3);
btn_4 = (Button)findViewById(R.id.btn_4);
MyBaseAdapter myBaseAdapter = new MyBaseAdapter(this,R.layout.list_item,show);
ListView lv = (ListView)findViewById(R.id.list);
btn_1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
insert(e_name.getText().toString(),e_age.getText().toString());
}
});
btn_2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
delete();
}
});
btn_3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
update(e_name.getText().toString(),e_age.getText().toString());
}
});
btn_4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
find(lv);
lv.setAdapter(myBaseAdapter);
}
});
}
//增加
public void insert(String name,String age){
SQLiteDatabase db = helper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put("s_name",name);
values.put("s_age",age);
long id = db.insert("stu",null,values);
db.close();
}
//删除
public void delete(){
SQLiteDatabase db = helper.getWritableDatabase();
int number = db.delete("stu",null,null);
db.close();
}
//修改
public int update(String name,String age){
SQLiteDatabase db = helper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put("s_age",age);
int number = db.update("stu",values,"s_name=?",new String[]{name});
db.close();
return number;
}
//查找
public void find(View view){
SQLiteDatabase db = helper.getReadableDatabase();
Cursor cursor = db.rawQuery("select * from stu",null);
if(cursor.getCount() != 0){
while(cursor.moveToNext()){
Student s = new Student(this);
s.setId(cursor.getInt(0));
s.setName(cursor.getString(1));
s.setAge(cursor.getString(2));
show.add(s);
}
}
cursor.close();
db.close();
}
class MyBaseAdapter extends BaseAdapter{
public MyBaseAdapter(MainActivity mainActivity, int list_item, List<Student> show) {
}
@Override
public int getCount() {
return show.size();
}
@Override
public Object getItem(int position) {
return show.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = View.inflate(MainActivity.this,R.layout.list_item,null);
TextView tvid = (TextView)findViewById(R.id.textView5);
TextView tvname = (TextView)findViewById(R.id.textView6);
TextView tvage = (TextView)findViewById(R.id.textView7);
tvid.setText(show.get(position)+"_id");
tvname.setText(show.get(position)+"e_name");
tvage.setText(show.get(position)+"e_age");
return view;
}
}
}
