SQLite EXP

最新推荐文章于 2025-05-25 13:06:38 发布

原创最新推荐文章于 2025-05-25 13:06:38 发布 · 1.1k 阅读

0 ·

CC 4.0 BY-SA版权

工程仓库专栏收录该内容

5 篇文章

订阅专栏

mainActivity

package com.example.a71979.sqlexp;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
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 Activity {
			/** Called when the activity is first created. */
			private DBAdapter dbAdepter ;

			private EditText nameText;
			private EditText classText;
			private EditText sidText;
			private EditText idText;

			private Button addButton=null;
			private Button queryAllButton=null;
			private Button clearButton=null;
			private Button deleteAllButton=null;
			private Button queryButton=null;
			private Button deleteButton=null;
			private Button updateButton=null;

			//private TextView labelView;
			//private TextView displayView;
			private ListView displayView;
			private List<String> list;
			private ArrayAdapter<String> adapter=null;
			
			@Override
			public void onCreate(Bundle savedInstanceState) {
				super.onCreate(savedInstanceState);
				setContentView(R.layout.layout);

				nameText = (EditText)findViewById(R.id.sName);
				classText = (EditText)findViewById(R.id.sClass);
				sidText = (EditText)findViewById(R.id.sID);
				idText = (EditText)findViewById(R.id.ID);

				//labelView = (TextView)findViewById(R.id.label);
				//displayView = (TextView)findViewById(R.id.display);
				displayView = (ListView)findViewById(R.id.list_view);

				addButton = (Button)findViewById(R.id.addNew);
        		queryAllButton = (Button)findViewById(R.id.showAll);
        		clearButton = (Button)findViewById(R.id.clearShow);
       			deleteAllButton = (Button)findViewById(R.id.deleteAll);
        
    		    queryButton = (Button)findViewById(R.id.queryID);
        		deleteButton = (Button)findViewById(R.id.deleteID);
        		updateButton = (Button)findViewById(R.id.updateID);
        
        
        		addButton.setOnClickListener(addButtonListener);
        		queryAllButton.setOnClickListener(queryAllButtonListener);
        		clearButton.setOnClickListener(clearButtonListener);
        		deleteAllButton.setOnClickListener(deleteAllButtonListener);
        
        		queryButton.setOnClickListener(queryButtonListener);
        		deleteButton.setOnClickListener(deleteButtonListener);
        		updateButton.setOnClickListener(updateButtonListener);

				list = new ArrayList<String>();
				adapter=new ArrayAdapter<String>(this,android.R.layout.simple_expandable_list_item_1,list);
				displayView.setAdapter(adapter);
				registerForContextMenu(displayView);

        		dbAdepter = new DBAdapter(this);
        		dbAdepter.open();
    }
    
    OnClickListener addButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {
			Student student = new Student();
			student.Name = nameText.getText().toString();
			student.sClass = classText.getText().toString();
			student.sID = sidText.getText().toString();
			long colunm = dbAdepter.insert(student);

			Student[] students = dbAdepter.queryAllData();
			list.removeAll(list);
			adapter.notifyDataSetChanged();
			if (students == null){
				return;
			}

			for (int i = 0; i< students.length; i++){
				adapter.add(students[i].ID+"  "+students[i].sID.toString()+"  "+students[i].sClass.toString()+"  "+students[i].Name.toString());
			}

		}
    };
    
    OnClickListener queryAllButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {
			Student[] students = dbAdepter.queryAllData();
			list.removeAll(list);
			adapter.notifyDataSetChanged();
			if (students == null){
				return;
			}

			for (int i = 0; i< students.length; i++){
				adapter.add(students[i].ID+"  "+students[i].sID.toString()+"  "+students[i].sClass.toString()+"  "+students[i].Name.toString());
			}

		}
    };
    
    OnClickListener clearButtonListener = new OnClickListener() {

		@Override
		public void onClick(View v) {
			list.removeAll(list);
			adapter.notifyDataSetChanged();
		}	
    };
    
    OnClickListener deleteAllButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {
			dbAdepter.deleteAllData();
			list.removeAll(list);
			adapter.notifyDataSetChanged();
		}	
    };
    
    OnClickListener queryButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {
			list.removeAll(list);
			adapter.notifyDataSetChanged();
			int id = Integer.parseInt(idText.getText().toString());
			Student[] students = dbAdepter.queryOneData(id);
			
			if (students == null){
				return;
			}
			for (int i = 0; i< students.length; i++){
				adapter.add(students[i].ID+"  "+students[i].sID.toString()+"  "+students[i].sClass.toString()+"  "+students[i].Name.toString());
			}
		}
    };
    
    OnClickListener deleteButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {

			long id = Integer.parseInt(idText.getText().toString());
			long result = dbAdepter.deleteOneData(id);


		}	
    };
    
    OnClickListener updateButtonListener = new OnClickListener() {
		@Override
		public void onClick(View v) {
			list.removeAll(list);
			adapter.notifyDataSetChanged();
			Student student = new Student();
			student.Name = nameText.getText().toString();
			student.sClass = classText.getText().toString();
			student.sID = sidText.getText().toString();
			long id = Integer.parseInt(idText.getText().toString());
			long count = dbAdepter.updateOneData(id, student);
			Student[] students = dbAdepter.queryOneData(id);

			if (students == null){
				return;
			}
			for (int i = 0; i< students.length; i++){
				adapter.add(students[i].ID+"  "+students[i].sID.toString()+"  "+students[i].sClass.toString()+"  "+students[i].Name.toString());
			}
		}
    };

}

DBAdapter

package com.example.a71979.sqlexp;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

public class DBAdapter {

	private static final String DB_NAME = "student.db";
	private static final String DB_TABLE = "studentinfo";
	private static final int DB_VERSION = 1;

	public static final String KEY_ID = "_id";
	public static final String KEY_NAME = "name";
	public static final String KEY_sClass = "sClass";
	public static final String KEY_SID = "sID";

	private SQLiteDatabase db;
	private final Context context;
	private DBOpenHelper dbOpenHelper;

	public DBAdapter(Context _context) {
	    context = _context;
	  }

	  /** Close the database */
	  public void close() {
		  if (db != null){
			  db.close();
			  db = null;
		  }
		}

	  /** Open the database */
	  public void open() throws SQLiteException {
		  dbOpenHelper = new DBOpenHelper(context, DB_NAME, null, DB_VERSION);
		  try {
			  db = dbOpenHelper.getWritableDatabase();
		  }
		  catch (SQLiteException ex) {
			  db = dbOpenHelper.getReadableDatabase();
		  }
		}


	  public long insert(Student student) {
	    ContentValues newValues = new ContentValues();

	    newValues.put(KEY_NAME, student.Name);
	    newValues.put(KEY_sClass, student.sClass);
	    newValues.put(KEY_SID, student.sID);

	    return db.insert(DB_TABLE, null, newValues);
	  }


	  public Student[] queryAllData() {
		  Cursor results =  db.query(DB_TABLE, new String[] { KEY_ID, KEY_NAME, KEY_sClass, KEY_SID},
				  null, null, null, null, null);
		  return ConvertToPeople(results);
	  }

	  public Student[] queryOneData(long id) {
		  Cursor results =  db.query(DB_TABLE, new String[] { KEY_ID, KEY_NAME, KEY_sClass, KEY_SID},
				  KEY_ID + "=" + id, null, null, null, null);
		  return ConvertToPeople(results);
	  }

	  private Student[] ConvertToPeople(Cursor cursor){
		  int resultCounts = cursor.getCount();
		  if (resultCounts == 0 || !cursor.moveToFirst()){
			  return null;
		  }
		  Student[] students = new Student[resultCounts];
		  for (int i = 0 ; i<resultCounts; i++){
			  students[i] = new Student();
			  students[i].ID = cursor.getInt(0);
			  students[i].Name = cursor.getString(cursor.getColumnIndex(KEY_NAME));
			  students[i].sClass = cursor.getString(cursor.getColumnIndex(KEY_sClass));
			  students[i].sID = cursor.getString(cursor.getColumnIndex(KEY_SID));

			  cursor.moveToNext();
		  }
		  return students;
	  }

	  public long deleteAllData() {
		  return db.delete(DB_TABLE, null, null);
	  }

	  public long deleteOneData(long id) {
		  return db.delete(DB_TABLE,  KEY_ID + "=" + id, null);
	  }

	  public long updateOneData(long id , Student student){
		  ContentValues updateValues = new ContentValues();
		  updateValues.put(KEY_NAME, student.Name);
		  updateValues.put(KEY_sClass, student.sClass);
		  updateValues.put(KEY_SID, student.sID);

		  return db.update(DB_TABLE, updateValues,  KEY_ID + "=" + id, null);
	  }

		/** ��̬Helper�࣬���ڽ��������ºʹ����ݿ�*/
	  private static class DBOpenHelper extends SQLiteOpenHelper {

		  public DBOpenHelper(Context context, String name, CursorFactory factory, int version) {
		    super(context, name, factory, version);
		  }

		  private static final String DB_CREATE = "create table " +
		    DB_TABLE + " (" + KEY_ID + " integer primary key autoincrement, " +
		    KEY_NAME+ " text not null, " + KEY_sClass+ " integer," + KEY_SID + " float);";

		  @Override
		  public void onCreate(SQLiteDatabase _db) {
		    _db.execSQL(DB_CREATE);
		  }

		  @Override
		  public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion) {		    
		    _db.execSQL("DROP TABLE IF EXISTS " + DB_TABLE);
		    onCreate(_db);
		  }
		}
	}

student

package com.example.a71979.sqlexp;

public class Student {
	public int ID = -1;
	public String Name;
	public String sClass;
	public String sID;
	
	@Override
	public String toString(){
		String result = "";
		result += "ID��" + this.ID + "��";
		result += "������" + this.Name + "��";
		result += "���䣺" + this.sClass + "�� ";
		result += "��ߣ�" + this.sID + "��";
		return result;
	}
}

layout

<?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">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="center_horizontal">


        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical">

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

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:text="姓名："
                    android:textSize="26dp" />

                <EditText
                    android:id="@+id/sName"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:ems="8"
                    android:inputType="textPersonName"
                    android:text="" />

            </LinearLayout>

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

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:text="班级："
                    android:textSize="26dp" />

                <EditText
                    android:id="@+id/sClass"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:ems="8"
                    android:inputType="textPersonName"
                    android:text="" />

            </LinearLayout>

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

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:text="学号："
                    android:textSize="26dp" />

                <EditText
                    android:id="@+id/sID"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:ems="8"
                    android:inputType="textPersonName"
                    android:text="" />

            </LinearLayout>

        </LinearLayout>

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

            <Button
                android:id="@+id/addNew"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="添加数据" />

            <Button
                android:id="@+id/showAll"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="全部显示" />

            <Button
                android:id="@+id/clearShow"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="清除显示" />

            <Button
                android:id="@+id/deleteAll"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="全部删除" />

        </LinearLayout>

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

            <TextView
                android:id="@+id/textView"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="ID:"
                android:textSize="20dp"/>

            <EditText
                android:id="@+id/ID"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:ems="3"
                android:inputType="textPersonName"
                android:text="" />

            <Button
                android:id="@+id/queryID"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="ID查询" />

            <Button
                android:id="@+id/deleteID"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="ID删除" />

            <Button
                android:id="@+id/updateID"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="ID更新" />

        </LinearLayout>

        <ListView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:id="@+id/list_view"/>

    </LinearLayout>
</LinearLayout>

Manifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.a71979.sqlexp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>