开发过程中使用Android自带的数据库,不仅安全性较好,而且数据存取的效果也较好。
附源代码
http://download.csdn.net/detail/wyx100/8670843
开发规划
主界面
完成数据的输入,触发保存
启动后界面
输入数据
数据显示界面
数据库读取数据后显示
删除记录
开发顺序
主界面
类代码
package com.example.sqlitetest; import android.os.Bundle; import android.app.Activity; import android.content.ContentValues; import android.content.Intent; import android.view.View; import android.widget.Button; import android.widget.EditText; public class ActivityMain_1 extends Activity { //声明EditText实例 private EditText et1,et2,et3; //声明Button实例 private Button button; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.main_1); //根据ID获得实例对象 et1 = (EditText) findViewById(R.id.EditText01); et2 = (EditText) findViewById(R.id.EditText02); et3 = (EditText) findViewById(R.id.EditText03); button = (Button) findViewById(R.id.button); //事件 button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String name=et1.getText().toString(); String url =et2.getText().toString(); String desc = et3.getText().toString(); ContentValues values = new ContentValues(); values.put("name", name); values.put("url", url); values.put("desc", desc); //实例化数据库帮助类 DBHelper helper = new DBHelper(getApplicationContext()); //打开数据库 helper.open(); //插入数据 helper.insert(values); //实例化Intent Intent intent = new Intent(ActivityMain_1.this,QueryActivity.class); startActivity(intent); helper.close(); } }); } }
界面布局
<?xml version="1.0" encoding="UTF-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:id="@+id/TextView01" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="网站名称" /> <EditText android:id="@+id/EditText01" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <TextView android:id="@+id/TextView02" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="URL" /> <EditText android:id="@+id/EditText02" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <TextView android:id="@+id/TextView03" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="网站描述" /> <EditText android:id="@+id/EditText03" android:layout_width="fill_parent" android:layout_height="wrap_content" android:height="100px" /> <Button android:id="@+id/button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="添加" /> </LinearLayout>
2.数据显示界面
类代码
package com.example.sqlitetest; import android.app.AlertDialog; import android.app.ListActivity; import android.content.DialogInterface; import android.database.Cursor; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ListView; import android.widget.SimpleCursorAdapter; public class QueryActivity extends ListActivity { private ListView listView; private Cursor c; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); //setContentView(R.layout.row); //实例化数据库帮助类 final DBHelper help = new DBHelper(this); help.open(); c= help.query(); query(); //提示对话框 final AlertDialog.Builder builder = new AlertDialog.Builder(this); listView.setOnItemClickListener(new OnItemClickListener(){ @Override public void onItemClick(AdapterView<?> parent, View view,int position, long id) { final long temp = id; builder.setMessage("真的要删除该条记录吗?").setPositiveButton("是", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { System.out.println("yes"); help.del((int)temp); //重新查询 //query(); Cursor c = help.query(); //列表项数组 String[] from ={"_id","name","url","desc"}; //列表项ID int[] to ={R.id.text0,R.id.text1,R.id.text2,R.id.text3}; //适配器 SimpleCursorAdapter adapter = new SimpleCursorAdapter(getApplicationContext(),R.layout.row,c,from,to); ListView listView = getListView(); listView.setAdapter(adapter); } }).setNegativeButton("否", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub } }); builder.create(); builder.show(); } }); } @Override protected void onStop() { // TODO Auto-generated method stub super.onStop(); } public void query(){ //列表项数组 String[] from ={"_id","name","url","desc"}; //列表项ID int[] to ={R.id.text0,R.id.text1,R.id.text2,R.id.text3}; //适配器 SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,R.layout.row,c,from,to); //adapter.notifyDataSetChanged(); //列表视图 listView = getListView(); //为列表视图添加适配器 listView.setAdapter(adapter); } }
界面布局
<?xml version="1.0" encoding="UTF-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_gravity="center_vertical" > <TextView android:id="@+id/text0" android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingRight="10px" /> <TextView android:id="@+id/text1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingRight="10px" /> <TextView android:id="@+id/text2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingRight="10px" /> <TextView android:id="@+id/text3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingRight="10px" /> </LinearLayout>
数据库处理类
package com.example.sqlitetest; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; public class DBHelper extends SQLiteOpenHelper { private static final String DB_NAME="coll.db"; //???? private static final String TBL_NAME="logtable"; //????SQL??? private static final String CREATE_TBL = "create table logtable " + "(_id integer primary key autoincrement,name text,url text,desc text)"; //SQLiteDatabase??? private SQLiteDatabase db; public DBHelper(Context context) { super(context, DB_NAME, null, 2); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_TBL); } //?????? public void open(){ db = getWritableDatabase(); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO Auto-generated method stub } //?????? public void insert(ContentValues values){ db.insert(TBL_NAME, null, values); } //??????? public Cursor query(){ Cursor c = db.query(TBL_NAME, null, null, null, null, null, null); return c; } //??? public void del(int id){ db.delete(TBL_NAME, "_id=?", new String[]{String.valueOf(id)}); } //??????? public void close(){ if (db != null){ db.close(); } } }
启动配置文件
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.sqlitetest" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="18" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.example.sqlitetest.ActivityMain_1" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name="com.example.sqlitetest.QueryActivity"></activity> </application> </manifest>
时间: 2024-10-06 13:06:31