本文實例講述了Android編程使用內容提供者方式進行存儲的方法。分享給大家供大家參考，具體如下：
內容提供者(ContentProvider)主要作用是對外共享數據，如果數據通過內容提供者對外共享了，那么其他應用就可以從內容提供者中查詢到數據，并且可更新數據、刪除數據、添加數據，如果采用文件的操作模式對外共享數據，數據的訪問方式會因為存儲方式的不同導致數據的訪問方式無法得到統一，不同存儲方式文件對外進行共享其訪問的ApI是不一樣的，如果采用內容提供者對外共享數據就會統一了數據的訪問方式。采用統一的API訪問共享的數據。
創建內容提供者步驟
1.創建內容提供者需要繼承android.content.ContentProvider
2.清單文件中進行配置：
<!--android:name:指定內容提供者的類名，android:authorities：調用內容..名稱，隨意取 -->
<provider android:name=".PersonProvider" android:authorities="cn.test.providers.personprovider"/>
ContentProvider類主要方法
示例：
內容提供者類，實現數據的增刪改查
public class PersonProvider extends ContentProvider { //創建工具類實現Uri匹配 private static final UriMatcher MATCHER = new UriMatcher(UriMatcher.NO_MATCH); private static final int PERSONS = 1; private static final int PERSON = 2; static{ MATCHER.addURI("cn.test.providers.personprovider", "person", PERSONS); MATCHER.addURI("cn.test.providers.personprovider", "person/#", PERSON); } private DBOpenHelper dbOpenHelper = null; @Override public boolean onCreate() { dbOpenHelper = new DBOpenHelper(getContext()); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { SQLiteDatabase db = dbOpenHelper.getReadableDatabase(); switch (MATCHER.match(uri)) { case PERSONS: // 獲取person表中的所有數據 /person return db.query("person", projection, selection, selectionArgs, null, null, sortOrder); case PERSON: // 獲取person表中的指定id的數據 /person/20 long id = ContentUris.parseId(uri); String where = "personid="+ id; if(selection!=null && !"".equals(selection.trim())){ where += " and "+ selection; } return db.query("person", projection, where, selectionArgs, null, null, sortOrder); default: throw new IllegalArgumentException("Unknown Uri:"+ uri); } } @Override public String getType(Uri uri) { // TODO Auto-generated method stub return null; } @Override public Uri insert(Uri uri, ContentValues values) { //取得數據庫操作實例 SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); switch (MATCHER.match(uri)) { case PERSONS: //執行添加，返回行號，如果主健字段是自增長的，那么行號會等于主鍵id long rowid = db.insert("person", "name", values); //得到拼好的uri Uri insertUri = ContentUris.withAppendedId(uri, rowid); //發出數據變化通知(person表的數據發生變化) getContext().getContentResolver().notifyChange(uri, null); return insertUri; default: //不能識別uri throw new IllegalArgumentException("Unknown Uri:"+ uri); } } @Override public int delete(Uri uri, String selection, String[] selectionArgs) { SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); //受影響的行數 int num = 0; switch (MATCHER.match(uri)) { case PERSONS: // 刪除person表中的所有數據 /person num = db.delete("person", selection, selectionArgs); break; case PERSON: // 刪除person表中的指定id的數據 /person/20 long id = ContentUris.parseId(uri); String where = "personid="+ id; if(selection!=null && !"".equals(selection.trim())){ where += " and "+ selection; } num = db.delete("person", where, selectionArgs); break; default: throw new IllegalArgumentException("Unknown Uri:"+ uri); } return num; } @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); int num = 0; switch (MATCHER.match(uri)) { case PERSONS: // 更新person表中的所有數據 /person num = db.update("person", values, selection, selectionArgs); break; case PERSON: // 更新person表中的指定id的數據 /person/20 long id = ContentUris.parseId(uri); String where = "personid="+ id; if(selection!=null && !"".equals(selection.trim())){ where += " and "+ selection; } num = db.update("person", values, where, selectionArgs); break; default: throw new IllegalArgumentException("Unknown Uri:"+ uri); } return num; }}其他工程中訪問：
public class AccessContentProiderTest extends AndroidTestCase { public void testInsert() throws Throwable{ ContentResolver resolver = getContext().getContentResolver(); Uri uri = Uri.parse("content://cn.test.providers.personprovider/person"); ContentValues values = new ContentValues(); values.put("name", "lili"); values.put("phone", "110"); values.put("amount", "3000000000"); resolver.insert(uri, values); } public void testDelete() throws Throwable{ ContentResolver resolver = getContext().getContentResolver(); Uri uri = Uri.parse("content://cn.test.providers.personprovider/person"); int num =resolver.delete(uri, null, null); } public void testUpdate() throws Throwable{ ContentResolver resolver = getContext().getContentResolver(); Uri uri = Uri.parse("content://cn.test.providers.personprovider/person/65"); ContentValues values = new ContentValues(); values.put("amount", 500); resolver.update(uri, values, null, null); } public void testQuery() throws Throwable{ ContentResolver resolver = getContext().getContentResolver(); Uri uri = Uri.parse("content://cn.test.providers.personprovider/person/65"); Cursor cursor = resolver.query(uri, null, null, null, "personid asc"); while(cursor.moveToNext()){ String name = cursor.getString(cursor.getColumnIndex("name")); Log.i("AccessContentProviderTest", name); } }}希望本文所述對大家Android程序設計有所幫助。
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