• Android对SQLite的基础操作(用于初学者,少走弯路)


    1.建立DatabaseHelper类并继承SQLiteOpenHelper

    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteDatabase.CursorFactory;
    import android.database.sqlite.SQLiteOpenHelper;

    public class DatabaseHelper  extends SQLiteOpenHelper{

     private final static String dataBaseName="sharp.db";
     private final static String tableName="person";
     private final static int version=1;
     public DatabaseHelper(Context context) {
      super(context,dataBaseName,null,version);
      // TODO Auto-generated constructor stub
     }

     @Override
     public void onCreate(SQLiteDatabase db) {
      // TODO Auto-generated method stub
      String sql="CREATE TABLE "+tableName+"(name text not null,age text not null)";
      db.execSQL(sql);
      
     }

     @Override
     public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
      // TODO Auto-generated method stub
      
     }

    }

    2.在ActivityMain类中代码如下:

    package com.example.pro08;

    import android.os.Bundle;
    import android.app.Activity;
    import android.database.SQLException;
    import android.database.sqlite.SQLiteDatabase;
    import android.util.Log;
    import android.view.Menu;
    import android.view.View;
    import android.widget.Button;

    public class MainActivity extends Activity {
     DatabaseHelper dataHelper=new DatabaseHelper(this);
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
           
           
            Button btn1=(Button)findViewById(R.id.button1);
            btn1.setOnClickListener(new View.OnClickListener() {
       
       public void onClick(View arg0) {
        // TODO Auto-generated method stub
        SQLiteDatabase db = dataHelper.getWritableDatabase();
                    String sql="insert into person (name,age) values('wanghe','20')";
                   
        
          try {
            Log.i("SQL=", sql);
         
            db.execSQL(sql);
            setTitle("插入数据成功");
           } catch (SQLException e) {
            setTitle("插入数据失败");
           }

       }
      });
        }

        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            getMenuInflater().inflate(R.menu.activity_main, menu);
            return true;
        }
    }

    3.在activity_main视图中如下:

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:layout_marginLeft="106dp"
            android:layout_marginTop="94dp"
            android:text="Button" />

    </RelativeLayout>

    4.然后运行,点击Button,在Tag中可看到

    5至于数据库就在你运行后在DDMS中找data/data/你的项目名/database/sharp.db。

    同时菜鸟沦落人,互相学习吧

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  • 原文地址:https://www.cnblogs.com/wangheblog/p/2752801.html
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