android实现一个简单的增删改查的数据库操作

效果图

‘package com.example.empmanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

public class AddEmpActivity extends Activity {

private EditText empname,empno,empage,empsal;

private Button save,clear;

DBHelper helper=new DBHelper(this);

MainActivity activity=new MainActivity();

empInfo emp;

protected void onCreate(Bundle savedInstanceState) {

// TODO Auto-generated method stub

super.onCreate(savedInstanceState);

setContentView(yout.add_emp);

//初始化

empname=(EditText) findViewById(R.id.empname);

empno=(EditText) findViewById(R.id.empno);

empage=(EditText) findViewById(R.id.empage);

empsal=(EditText) findViewById(R.id.empsal);

save=(Button) findViewById(R.id.save);

clear=(Button) findViewById(R.id.clear);

save.setOnClickListener(new OnClickListener() {

public void onClick(View v) {

// TODO Auto-generated method stub

String name=empname.getText().toString();

String no=empno.getText().toString();

String age=empage.getText().toString();

String sal=empsal.getText().toString();

if(name.length()>0&&no.length()>0&&age.length()>0&&sal.length()>0){

helper.insertEmp(name,no,age,sal);

Toast.makeText(AddEmpActivity.this, "增加成功", 1000).show();

Intent intent=new Intent(AddEmpActivity.this,MainActivity.class);

startActivity(intent);

}

else{

Toast.makeText(AddEmpActivity.this, "增加失败", 1000).show();

}

}

});

clear.setOnClickListener(new OnClickListener() {

public void onClick(View v) {

// TODO Auto-generated method stub

empname.setText("");

empno.setText("");

empage.setText("");

empsal.setText("");

}

});

}

}

主活动页面

package com.example.empmanager;

import android.os.Bundle;

import android.provider.ContactsContract.Data;

import monDataKinds.Phone; import android.app.Activity;

import android.app.AlertDialog;

import android.app.AlertDialog.Builder;

import android.app.ListActivity;

import android.content.Context;

import android.content.DialogInterface;

import android.content.Intent;

import android.database.Cursor;

import android.view.ContextMenu;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.view.ContextMenu.ContextMenuInfo;

import android.view.View.OnClickListener;

import android.widget.AdapterView;

import android.widget.AdapterView.AdapterContextMenuInfo; import android.widget.Button;

import android.widget.CheckBox;

import android.widget.ListView;

import android.widget.RelativeLayout;

import android.widget.SimpleAdapter;

import android.widget.SimpleCursorAdapter;

import android.widget.TextView;

import android.widget.Toast;

import android.widget.AdapterView.OnItemClickListener;

public class MainActivity extends Activity {

private Button insert,delete,update,select;

private TextView show_name,show_no,show_age,show_sal;