編輯:關於Android編程
本文實例講述了Android操作SQLite數據庫(增、刪、改、查、分頁等)及ListView顯示數據的方法。分享給大家供大家參考,具體如下:
由於剛接觸android開發,故此想把學到的基礎知識記錄一下,以備查詢,故此寫的比較啰嗦:
步驟如下:
一、介紹:
此文主要是介紹怎麼使用android自帶的數據庫SQLite,以及把後台的數據用ListView控件顯示
二、新建一個android工程——DBSQLiteOperate
工程目錄:

三、清單列表AndroidManifest.xml的配置為:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.dboperate"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<!--單元測試 加這句-->
<uses-library android:name="android.test.runner" />
<activity
android:name=".DBSQLiteOperateActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<instrumentation android:name="android.test.InstrumentationTestRunner"
android:targetPackage="com.example.dboperate"
android:label="Test for my app"/>
</manifest>
四、main.xml配置清單:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="@+id/name"
android:layout_width="100dip"
android:layout_height="wrap_content"
android:text="@string/name"
android:gravity="center"/>
<TextView
android:id="@+id/phone"
android:layout_width="100dip"
android:layout_height="wrap_content"
android:text="@string/phone"
android:gravity="center"/>
<TextView
android:id="@+id/amount"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/amount"
android:gravity="center"/>
</LinearLayout>
<ListView
android:id="@+id/listView"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
</ListView>
</LinearLayout>
五、item.xml配置清單:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal" >
<TextView
android:id="@+id/name"
android:layout_width="100dip"
android:layout_height="wrap_content"
android:text="@string/name"
android:gravity="center"/>
<TextView
android:id="@+id/phone"
android:layout_width="100dip"
android:layout_height="wrap_content"
android:text="@string/phone"
android:gravity="center"/>
<TextView
android:id="@+id/amount"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/amount"
android:gravity="center"/>
</LinearLayout>
六、string.xml配置清單:
<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">Hello World, DBSQLiteOperateActivity!</string> <string name="app_name">ExampleDBSQLiteOperate8</string> <string name="name">姓名</string> <string name="phone">電話</string> <string name="amount">存款</string> </resources>
七、DBSQLiteOperateActivity.java Activity類的源碼:
package com.example.dboperate;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.example.adapter.PersonAdapter;
import com.example.domain.Person;
import com.example.service.PersonService;
import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.SimpleCursorAdapter;
import android.widget.Toast;
public class DBSQLiteOperateActivity extends Activity {
ListView listView;
PersonService personService;
OnItemClickListener listViewListener;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
listViewListener = new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//得到listView控件
ListView listView = (ListView)parent;
//1、如果使用自定義適配器,返回的是Person對象
//得到該條目數據
// Person person = (Person)listView.getItemAtPosition(position);
// //廣播出去
// Toast.makeText(getApplicationContext(), person.toString(), Toast.LENGTH_LONG).show();
//2、如果使用showList2()方法中的適配器時,則取得的值是不一樣的,返回的是cursor
// Cursor cursor = (Cursor)listView.getItemAtPosition(position);
// int personid = cursor.getInt(cursor.getColumnIndex("_id"));
// Toast.makeText(getApplicationContext(), personid+"", Toast.LENGTH_LONG).show();
//3、如果使用showList()方法中的適配器時,則取得的值是不一樣的,返回的是map
@SuppressWarnings("unchecked")
Map<String,Object> map = (Map)listView.getItemAtPosition(position);
String name = map.get("name").toString();
String personid = map.get("personid").toString();
Toast.makeText(getApplicationContext(), personid +"-"+ name, Toast.LENGTH_LONG).show();
}
};
listView = (ListView) this.findViewById(R.id.listView);
listView.setOnItemClickListener(listViewListener);
personService = new PersonService(this);
showList();
}
private void showList() {
List<Person> persons = personService.getScrollData(0, 50);
List<HashMap<String,Object>> data = new ArrayList<HashMap<String,Object>>();
for(Person person : persons){
HashMap<String,Object> item = new HashMap<String,Object>();
item.put("name", person.getName());
item.put("phone", person.getPhone());
item.put("amount", person.getAmount());
item.put("personid", person.getId());
data.add(item);
}
SimpleAdapter adapter = new SimpleAdapter(this,data,R.layout.item, new String[]{"name","phone","amount"}, new int[]{R.id.name,R.id.phone,R.id.amount});
listView.setAdapter(adapter);
}
public void showList2(){
Cursor cursor = personService.getCursorScrollData(0, 50);
//該適配器要求返回的結果集cursor必須包含_id字段,所以需要對取得結果集進行處理
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,R.layout.item,cursor,new String[]{"name","phone","amount"}, new int[]{R.id.name,R.id.phone,R.id.amount} );
listView.setAdapter(adapter);
}
/**
* 自定義適配器
*/
public void showList3(){
List<Person> persons = personService.getScrollData(0, 50);
/**
* 第一個參數:上下文context,第二個參數:要顯示的數據,第三個參數:綁定的條目界面
*/
PersonAdapter adapter = new PersonAdapter(this, persons, R.layout.item);
listView.setAdapter(adapter);
}
}
八、person.java 實體類 源碼:
package com.example.domain;
public class Person {
private Integer id;
private String name;
private String phone;
private Integer amount;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public Person(String name, String phone) {
this.name = name;
this.phone = phone;
}
public Person(Integer id, String name, String phone,Integer amount) {
super();
this.id = id;
this.name = name;
this.phone = phone;
this.amount = amount;
}
public Person() {
super();
}
public Integer getAmount() {
return amount;
}
public void setAmount(Integer amount) {
this.amount = amount;
}
@Override
public String toString() {
return "Person [id=" + id + ", name=" + name + ", phone=" + phone
+ ", amount=" + amount + "]";
}
}
九、DBOperateHelper.java 業務類源碼:
package com.example.service;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class DBOperateHelper extends SQLiteOpenHelper {
public DBOperateHelper(Context context) {//默認創建的數據庫文件保存在<包名>/database/
//第一個參數是上下文,第二個參數是數據庫名稱,第三個是游標工廠為null時使用 數據庫默認的游標工廠,第四個是數據庫版本號但是不能為0,一般大於0
super(context, "smallpig", null, 4);
}
/**
* 數據庫每一次被創建時被調用
*/
@Override
public void onCreate(SQLiteDatabase sqldb) {
sqldb.execSQL("create table person(personid integer primary key autoincrement,name varchar(20),phone varchar(12) null)");
}
/**
* 每一次數據庫版本號發生變動時觸發此方法
* 比如如果想往數據庫中再插入一些表、字段或者其他信息時通過修改數據庫版本號來觸發此方法
*/
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//db.execSQL("alter table person add phone varchar(12) null");\
db.execSQL("alter table person add amount Integer null");
}
}
十、PersonService.java 業務類源碼:
package com.example.service;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import com.example.domain.Person;
public class PersonService {
private DBOperateHelper dbOperateHelper;
public PersonService(Context context) {
this.dbOperateHelper = new DBOperateHelper(context);
}
/**
* 保存記錄
* @param person
*/
public void save(Person person){
//得到數據庫實例,裡面封裝了數據庫操作方法
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
//sqldb.execSQL("insert into person(name,phone) values('"+person.getName()+"','"+person.getPhone()+"')");
//利用占位符可以避免注入,但是注意數組參與與占位符對應的字段要一一對應
sqldb.execSQL("insert into person(name,phone,amount) values(?,?,?)",new Object[]{person.getName(),person.getPhone(),person.getAmount()});
//關閉數據庫
sqldb.close();
}
/**
* 刪除記錄
* @param id
*/
public void delete(Integer id){
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
sqldb.execSQL("delete from person where personid=?",new Object[]{id});
sqldb.close();
}
/**
* 更新記錄
* @param person
*/
public void update(Person person){
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
sqldb.execSQL("update person set name=?,phone=?,amount=? where personid=?",new Object[]{person.getName(),person.getPhone(),person.getAmount(),person.getId()});
sqldb.close();
}
/**
* 通過ID查詢記錄
* @param id
* @return
*/
public Person find(Integer id){
/**
* getWritableDatabase 與 getReadableDatabase 的區別:
* getReadableDatabase會先返回getWritableDatabase(可寫),如果調用getWritableDatabase失敗
* 則才會調用getReadableDatabase後續方法,使數據庫只讀
* 當寫入的數據超過數據庫大小則調用getWritableDatabase會失敗
* 所以只讀時則可以使用此方法,其它情況(只要不是超過數據庫大小)也可以使用此方法
*/
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
Cursor cursor = sqldb.rawQuery("select * from person where personid=?", new String[]{String.valueOf(id)});
int personid;
String name;
String phone;
int amount;
Person person = null;
if(cursor.moveToFirst()){
personid = cursor.getInt(cursor.getColumnIndex("personid"));
name = cursor.getString(cursor.getColumnIndex("name"));
phone = cursor.getString(cursor.getColumnIndex("phone"));
amount = cursor.getInt(cursor.getColumnIndex("amount"));
person = new Person(personid,name,phone,amount);
}
cursor.close();
return person;
}
/**
* 返回指定長度記錄,limit 3,5,適用於分頁
* @param offset 起始
* @param maxResult 長度
* @return
*/
public List<Person> getScrollData(int offset,int maxResult){
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
Cursor cursor = sqldb.rawQuery("select * from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});
int personid;
String name;
String phone;
int amount;
Person person = null;
List<Person> persons = new ArrayList<Person>();
while(cursor.moveToNext()){
personid = cursor.getInt(cursor.getColumnIndex("personid"));
name = cursor.getString(cursor.getColumnIndex("name"));
phone = cursor.getString(cursor.getColumnIndex("phone"));
amount = cursor.getInt(cursor.getColumnIndex("amount"));
person = new Person(personid,name,phone,amount);
persons.add(person);
}
cursor.close();
return persons;
}
/**
* 返回cursor
* @param offset 起始
* @param maxResult 長度
* @return
*/
public Cursor getCursorScrollData(int offset,int maxResult){
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
Cursor cursor = sqldb.rawQuery("select personid as _id,name,phone,amount from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});
return cursor;
}
/**
* 返回總記錄數
* @return
*/
public long getCount(){
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
Cursor cursor = sqldb.rawQuery("select count(*) from person", null);
//該查詢語句值返回一條語句
cursor.moveToFirst();
long result = cursor.getLong(0);
cursor.close();
return result;
}
public void payment(){
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
sqldb.beginTransaction();//開啟事務
try{
sqldb.execSQL("update person set amount = amount -10 where personid=1");
sqldb.execSQL("update person set amount = amount + 10 where personid=2");
sqldb.setTransactionSuccessful();//設置事務標志位true
} finally {
//結束事務:有兩種情況:commit\rollback,事務提交或者回滾是由事務的標識決定的
//事務為ture則提交,事務為flase則回滾,默認為false
sqldb.endTransaction();
}
}
}
十一、OtherPersonService.java 業務類源碼:
package com.example.service;
import java.util.ArrayList;
import java.util.List;
import com.example.domain.Person;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class OtherPersonService {
private DBOperateHelper dbOperateHelper;
public OtherPersonService(Context context) {
this.dbOperateHelper = new DBOperateHelper(context);
}
/**
* 保存記錄
* @param person
*/
public void save(Person person){
//得到數據庫實例,裡面封裝了數據庫操作方法
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
//sqldb.execSQL("insert into person(name,phone) values('"+person.getName()+"','"+person.getPhone()+"')");
//利用占位符可以避免注入,但是注意數組參與與占位符對應的字段要一一對應
//sqldb.execSQL("insert into person(name,phone) values(?,?)",new Object[]{person.getName(),person.getPhone()});
ContentValues values = new ContentValues();
values.put("name", person.getName());
values.put("phone", person.getPhone());
values.put("amount", person.getAmount());
//第一個參數是表名,第三個為字段值集合,第二個參數是空值字段,當第三個字段值集合為空時,系統會自動插入一條第二個參數為空的sql語句
//否則當第三個參數為空時,如果第二個參數也為空,那麼插入表就會找不到插入的字段信息,會報錯
sqldb.insert("person", "name", values );
//關閉數據庫
sqldb.close();
}
/**
* 刪除記錄
* @param id
*/
public void delete(Integer id){
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
//sqldb.execSQL("delete from person where personid=?",new Object[]{id});
//第一個參數是表名,第二個是where後面的條件用占位符表示,第三個對應占位符為參數值
sqldb.delete("person", "personid=?", new String[]{Integer.toString(id)});
sqldb.close();
}
/**
* 更新記錄
* @param person
*/
public void update(Person person){
SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
//sqldb.execSQL("update person set name=?,phone=? where personid=?",new Object[]{person.getName(),person.getPhone(),person.getId()});
//第一個參數為表名,第二個是一個更新值集合,采用鍵值對的形式,每個更新的字段對應更新值
//第三個參數是where後面條件字段用占位符標識,第四個參數是對應where占位符的值
ContentValues values = new ContentValues();
values.put("name", person.getName());
values.put("phone", person.getPhone());
values.put("amount", person.getAmount());
sqldb.update("person", values , "personid=?", new String[]{person.getId().toString()});
sqldb.close();
}
/**
* 通過ID查詢記錄
* @param id
* @return
*/
public Person find(Integer id){
/**
* getWritableDatabase 與 getReadableDatabase 的區別:
* getReadableDatabase會先返回getWritableDatabase(可寫),如果調用getWritableDatabase失敗
* 則才會調用getReadableDatabase後續方法,使數據庫只讀
* 當寫入的數據超過數據庫大小則調用getWritableDatabase會失敗
* 所以只讀時則可以使用此方法,其它情況(只要不是超過數據庫大小)也可以使用此方法
*/
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
//Cursor cursor = sqldb.rawQuery("select * from person where personid=?", new String[]{String.valueOf(id)});
//第一個參數是表名;第二個參數是查詢顯示的字段,null時默認查詢顯示所有字段;
//第三個參數是where查詢條件占位符;第四個是占位符對應的值;
//第五個參數是group by條件;第六個是having條件;第七個是order by條件
Cursor cursor = sqldb.query("person", null, "personid=?", new String[]{id.toString()}, null, null, null);
int personid;
String name;
String phone;
int amount;
Person person = null;
if(cursor.moveToFirst()){
personid = cursor.getInt(cursor.getColumnIndex("personid"));
name = cursor.getString(cursor.getColumnIndex("name"));
phone = cursor.getString(cursor.getColumnIndex("phone"));
amount = cursor.getInt(cursor.getColumnIndex("amount"));
person = new Person(personid,name,phone,amount);
}
cursor.close();
return person;
}
/**
* 返回指定長度記錄,limit 3,5,適用於分頁
* @param offset 起始
* @param maxResult 長度
* @return
*/
public List<Person> getScrollData(int offset,int maxResult){
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
//Cursor cursor = sqldb.rawQuery("select * from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});
//第一個參數是表名;第二個參數是查詢顯示的字段,null時默認查詢顯示所有字段;
//第三個參數是where查詢條件占位符;第四個是占位符對應的值;
//第五個參數是group by條件;第六個是having條件;第七個是order by條件
//第八個參數是limit ?,? 條件
Cursor cursor = sqldb.query("person", null, null, null, null, null, "personid",offset+","+maxResult);
int personid;
String name;
String phone;
int amount;
Person person = null;
List<Person> persons = new ArrayList<Person>();
while(cursor.moveToNext()){
personid = cursor.getInt(cursor.getColumnIndex("personid"));
name = cursor.getString(cursor.getColumnIndex("name"));
phone = cursor.getString(cursor.getColumnIndex("phone"));
amount = cursor.getInt(cursor.getColumnIndex("amount"));
person = new Person(personid,name,phone,amount);
persons.add(person);
}
cursor.close();
return persons;
}
/**
* 返回總記錄數
* @return
*/
public long getCount(){
SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
//Cursor cursor = sqldb.rawQuery("select count(*) from person", null);
//第一個參數是表名;第二個參數是查詢顯示的字段,null時默認查詢顯示所有字段;
//第三個參數是where查詢條件占位符;第四個是占位符對應的值;
//第五個參數是group by條件;第六個是having條件;第七個是order by條件
Cursor cursor = sqldb.query("person", new String[]{"count(*)"}, null, null, null, null, null);
//該查詢語句值返回一條語句
cursor.moveToFirst();
long result = cursor.getLong(0);
cursor.close();
return result;
}
}
十二、PersonServiceTest.java 單元測試類源碼:
package com.example.test;
import java.util.List;
import com.example.domain.Person;
import com.example.service.DBOperateHelper;
import com.example.service.PersonService;import android.test.AndroidTestCase;
import android.util.Log;
public class PersonServiceTest extends AndroidTestCase {
public void testCreateDB() throws Exception{
DBOperateHelper dbHelper = new DBOperateHelper(getContext());
dbHelper.getWritableDatabase();
}
public void testSave() throws Exception{
PersonService ps = new PersonService(getContext());
for(int i=1;i<=100;i++){
Person person = new Person();
person.setName("我是"+i);
person.setPhone(String.valueOf(Long.parseLong("18888888800")+i));
ps.save(person);
Log.i("PersonService",person.toString());
}
}
public void testDelete() throws Exception{
PersonService ps = new PersonService(getContext());
ps.delete(10);
}
public void testUpdate() throws Exception{
PersonService ps = new PersonService(getContext());
ps.update(new Person(1,"xiaopang","18887654321",0));
}
public void testFind() throws Exception{
PersonService ps = new PersonService(getContext());
Person person = ps.find(1);
Log.i("PersonService", person.toString());
}
public void testGetScrollData() throws Exception{
PersonService ps = new PersonService(getContext());
List<Person> persons = ps.getScrollData(3, 5);
for(Person person:persons){
Log.i("PersonService",person.toString());
}
}
public void testGetCount() throws Exception{
PersonService ps = new PersonService(getContext());
Long count = ps.getCount();
Log.i("PersonService",count.toString());
}
public void testUpdateAmount() throws Exception{
PersonService ps = new PersonService(getContext());
Person person1 = ps.find(1);
Person person2 = ps.find(2);
person1.setAmount(100);
person2.setAmount(100);
ps.update(person1);
ps.update(person2);
}
public void testPayment() throws Exception{
PersonService ps = new PersonService(getContext());
ps.payment();
}
}
十三、OtherPersonServiceTest 單元測試類源碼:
package com.example.test;
import java.util.List;
import com.example.domain.Person;
import com.example.service.DBOperateHelper;
import com.example.service.OtherPersonService;
import android.test.AndroidTestCase;
import android.util.Log;
public class OtherPersonServiceTest extends AndroidTestCase {
public void testCreateDB() throws Exception{
DBOperateHelper dbHelper = new DBOperateHelper(getContext());
dbHelper.getWritableDatabase();
}
public void testSave() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
for(int i=1;i<=100;i++){
Person person = new Person();
person.setName("我是"+i);
person.setPhone(String.valueOf(Long.parseLong("18888888800")+i));
ps.save(person);
Log.i("PersonService",person.toString());
}
}
public void testDelete() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
ps.delete(10);
}
public void testUpdate() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
ps.update(new Person(1,"xiaopang","18887654321",0));
}
public void testFind() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
Person person = ps.find(1);
Log.i("PersonService", person.toString());
}
public void testGetScrollData() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
List<Person> persons = ps.getScrollData(3, 5);
for(Person person:persons){
Log.i("PersonService",person.toString());
}
}
public void testGetCount() throws Exception{
OtherPersonService ps = new OtherPersonService(getContext());
Long count = ps.getCount();
Log.i("PersonService",count.toString());
}
}
十四、注意事項以及相關知識點:
1、掌握SQLite數據庫如何創建數據庫、建立表、維護字段等操作
繼承SQLiteOpenHelper類,構造函數調用父類構造函數創建數據庫,利用onCreate創建表,利用onUpgrade更新表字段信息
2、掌握SQLite數據庫如何增、刪、改、查以及分頁
取得SQLiteDatabase的實例,然後調用該實例的方法可以完成上述操作
SQLiteDataBase提供兩種操作上述功能的方式:一是直接調用execSQL書寫sql語句,另一種是通過insert、update、delete、query等方法來傳值來拼接sql,前一種適合熟練掌握sql 語句的
3、對需要數據同步的處理請添加事務處理,熟悉事務的處理方式
4、了解各個方法參數的意義以及傳值
5、掌握ListView顯示後台數據的使用方法
SimpleAdapter、SimpleCursorAdapter以及自定義適配器的使用,以及OnItemClickListener取值時各個適配器返回值的區別以及取值方法
6、多學、多記、多練、多思,加油!
更多關於Android相關內容感興趣的讀者可查看本站專題:《Android開發入門與進階教程》、《Android通信方式總結》、《Android基本組件用法總結》、《Android視圖View技巧總結》、《Android布局layout技巧總結》及《Android控件用法總結》
希望本文所述對大家Android程序設計有所幫助。
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