Android数据存储之三SQLite嵌入式数据库(2)

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      5.编写测试类
      编写一个针对ContactsService的测试类，测试ContactsService类中的各个方法是否正确。

packagecom.changcheng.sqlite.test;   importjava.util.List; importcom.changcheng.sqlite.MyOpenHelper; importcom.changcheng.sqlite.entity.Contact; importcom.changcheng.sqlite.service.ContactsService; importandroid.database.Cursor; importandroid.test.AndroidTestCase; importandroid.util.Log;   publicclassContactsServiceTestextendsAndroidTestCase {           privatestaticfinalStringTAG="ContactsServiceTest";           //测试创建表         publicvoidtestCreateTable()throwsThrowable {                   MyOpenHelper openHelper =newMyOpenHelper(this.getContext());                   openHelper.getWritableDatabase();         }           //测试save         publicvoidtestSave()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   Contact contact1 =newContact(null,"tom","13898679876");                   Contact contact2 =newContact(null,"lili","13041094909");                   Contact contact3 =newContact(null,"jack","13504258899");                   Contact contact4 =newContact(null,"heary","1335789789");                   contactsService.save(contact1);                   contactsService.save(contact2);                   contactsService.save(contact3);                   contactsService.save(contact4);         }           //测试find         publicvoidtestFind()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   Contact contact = contactsService.find(1);                   Log.i(TAG, contact.toString());         }           //测试update         publicvoidtestUpdate()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   Contact contact = contactsService.find(1);                   contact.setPhone("1399889955");                   contactsService.update(contact);         }           //测试getCount         publicvoidtestGetCount()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   Log.i(TAG, contactsService.getCount() +"");         }           //测试getScrollData         publicvoidtestGetScrollData()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   List<Contact> contacts = contactsService.getScrollData(0, 3);                   Log.i(TAG, contacts.toString());         }                  //测试getScrollDataCursor         publicvoidtestGetScrollDataCursor()throwsThrowable {                   ContactsService contactsService =newContactsService(this.getContext());                   Cursor cursor = contactsService.getScrollDataCursor(0, 3);                   while(cursor.moveToNext()) {                            Contact contact =newContact(cursor.getInt(0),                                               cursor.getString(1), cursor.getString(2));                            Log.i(TAG, contact.toString());                   }         }   }

      启用测试功能，不要忘记在AndroidManifest.xml文件中加入测试环境。为application元素添加一个子元素：<uses-library android:name="android.test.runner"/>，为application元素添加一个兄弟元素：<instrumentation android:name="android.test.InstrumentationTestRunner"     android:targetPackage="com.changcheng.sqlite" android:label="Tests for My App" />。
 
      SQLite数据库以单个文件存储，就像微软的Access数据库。有一个查看SQLite数据库文件的工具——SQLite Developer，我们可以使用它来查看数据库。Android将创建的数据库存放在”/data/data/ com.changcheng.sqlite/databases/contacts”，我们将它导出然后使用SQLite Developer打开。
 
      6.分页显示数据
      我们在ContactsService类中，提供了一个获取分页数据的方法。我们将调用它获取的数据，使用ListView组件显示出来。
 
      编辑mail.xml：

<?xmlversion="1.0"encoding="utf-8"?> <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"         android:orientation="vertical"android:layout_width="fill_parent"         android:layout_height="fill_parent">         <!-- ListView -->         <ListViewandroid:layout_width="fill_parent"                   android:layout_height="fill_parent"android:id="@+id/listView"/>   </LinearLayout>

 
在mail.xml所在目录里添加一个contactitem.xml：

<?xmlversion="1.0"encoding="utf-8"?> <RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android"         android:layout_width="wrap_content"android:layout_height="wrap_content">           <!-- contact.id -->         <TextViewandroid:layout_width="30dip"android:layout_height="wrap_content"                   android:textSize="20sp"android:id="@+id/tv_id"/>           <!-- contact.name -->         <TextViewandroid:layout_width="150dip"android:layout_height="wrap_content"                   android:textSize="20sp"android:layout_toRightOf="@id/tv_id"                   android:layout_alignTop="@id/tv_id"android:id="@+id/tv_name"/>           <!-- contact.phone -->         <TextViewandroid:layout_width="150dip"android:layout_height="wrap_content"                   android:textSize="20sp"android:layout_toRightOf="@id/tv_name"                   android:layout_alignTop="@id/tv_name"android:id="@+id/tv_phone"/>   </RelativeLayout>

 
 
      编辑AndroidSQLite类：

packagecom.changcheng.sqlite;   importjava.util.ArrayList; importjava.util.HashMap; importjava.util.List; importcom.changcheng.sqlite.R; importcom.changcheng.sqlite.entity.Contact; importcom.changcheng.sqlite.service.ContactsService; importandroid.app.Activity; importandroid.database.Cursor; importandroid.os.Bundle; importandroid.view.View; importandroid.widget.AdapterView; importandroid.widget.ListView; importandroid.widget.SimpleAdapter; importandroid.widget.Toast; importandroid.widget.AdapterView.OnItemClickListener;   publicclassAndroidSQLiteextendsActivity {         /** Called when the activity is first created. */         @Override         publicvoidonCreate(Bundle savedInstanceState) {                   super.onCreate(savedInstanceState);                   setContentView(R.layout.main);                   //获取分页数据                   ContactsService contactsService =newContactsService(this);                   List<Contact> contacts = contactsService.getScrollData(0, 3);                   //获取ListView                   ListView lv = (ListView)this.findViewById(R.id.listView);                   //生成List<? extends Map<String, ?>>数据                   List<HashMap<String, Object>> data =newArrayList<HashMap<String, Object>>();                   for(Contact contact : contacts) {                            HashMap<String, Object> item =newHashMap<String, Object>();                            item.put("_id", contact.get_id());                            item.put("name", contact.getName());                            item.put("phone", contact.getPhone());                            data.add(item);                   }                   //生成Adapter                   SimpleAdapter adapter =newSimpleAdapter(this, data,                                     R.layout.contactitem,newString[] {"_id","name","phone"},                                     newint[] { R.id.tv_id, R.id.tv_name, R.id.tv_phone});                   //设置ListView适配器                   lv.setAdapter(adapter);                                      //为ListView添加事件                   lv.setOnItemClickListener(newOnItemClickListener() {                              @Override                            publicvoidonItemClick(AdapterView<?> parent, View view,                                               intposition,longid) {                                     HashMap<String, Object> item = (HashMap<String, Object>) parent                                                       .getItemAtPosition((int) id);                                     Toast.makeText(AndroidSQLite.this, item.get("name").toString(),                                                        1).show();                            }                     });         } }

 
上面编写的分页显示数据比较麻烦，Android为我们提供了一个SimpleCursorAdapter类。使用它可以方便的显示分页数据。将AndroidSQLite类修改为：
      

packagecom.changcheng.sqlite;   importcom.changcheng.sqlite.R; importcom.changcheng.sqlite.service.ContactsService; importandroid.app.Activity; importandroid.database.Cursor; importandroid.os.Bundle; importandroid.widget.ListView; importandroid.widget.SimpleCursorAdapter;   publicclassAndroidSQLiteextendsActivity {         /** Called when the activity is first created. */         @Override         publicvoidonCreate(Bundle savedInstanceState) {                   super.onCreate(savedInstanceState);                   setContentView(R.layout.main);                     //获取分页数据                   ContactsService contactsService =newContactsService(this);                   Cursor cursor = contactsService.getScrollDataCursor(0, 3);                   //获取ListView                   ListView lv = (ListView)this.findViewById(R.id.listView);                   //创建Adapter                   SimpleCursorAdapter adapter =newSimpleCursorAdapter(this,                                     R.layout.contactitem, cursor,newString[] {"_id","name",                                                        "phone"},newint[] { R.id.tv_id, R.id.tv_name,                                                        R.id.tv_phone});                   //设置ListView适配器                   lv.setAdapter(adapter);                     //为ListView添加事件                   lv.setOnItemClickListener(newOnItemClickListener() {                              @Override                            publicvoidonItemClick(AdapterView<?> parent, View view,                                               intposition,longid) {                                     Cursor cursor = (Cursor) parent                                                        .getItemAtPosition((int) position);                                     Toast.makeText(AndroidSQLite.this, cursor.getString(1), 1)                                                        .show();                            }                   });         } }

 
      OK，在Android中的SQLite操作总结结束！