當(dāng)外部應(yīng)用要對ContentProvider中的數(shù)據(jù)進行操作的時候

1、當(dāng)外部應(yīng)用要對ContentProvider中的數(shù)據(jù)進行操作的時候，可以使用ContentResolver類來完成，要獲取ContentResolver對象，可以使用activity的getContentResolver方法。 contentResolver類提供了與contentProvider相同簽名的四個方法public Uri insert(URI uri,ContentValues values); 這個方法用于添加數(shù)據(jù)public int delete(Uri  uri,String selection,String selectionArgs) 這個方法用于刪

2、除數(shù)據(jù)public int update(Uri uri,ContentValues values,String selection,Stringp selectionArgs) 更新方法  下面用查詢方法詳細(xì)舉例 public class PersonProvider extends ContentProvider     private static final String TAG = "PersonContentProvider"    DBOpenHelper dbHelpe

3、r;       private static final int PERSONLIST = 1;       private static final int PERSON = 2;    private static UriMatcher matcher;    static       matcher = new UriMatcher(UriMatch

4、er.NO_MATCH);       matcher.addURI("vider.PersonProvider", "person", PERSONLIST);       matcher.addURI("vider.PersonProvider", "person/#", PERSON);     &#

5、160;    Override    public String getType(Uri uri)        switch (matcher.match(uri)            case PERSONLIST:/獲取所有記錄  就是這樣規(guī)定的 多條記錄返回這個        

6、      return "vnd.android.cursor.dir/personprovider.person"           case PERSON:/獲取單條記錄  單條記錄返回那個              return "vnd.android.cursor.

7、item/personprovider.person"           default:              throw new IllegalArgumentException("Uri IllegalArgument:"+ uri);        

8、60;         Override    public boolean onCreate()        dbHelper = new DBOpenHelper(this.getContext();       return true;         Override  

9、0; public Cursor query(Uri uri, String projection, String selection, String selectionArgs, String sortOrder)        /獲取數(shù)據(jù)庫操作的類       SQLiteDatabase db = dbHelper.getReadableDatabase();       /聲明一個游標(biāo)  

10、     Cursor cursor = null;       switch (matcher.match(uri)            case PERSONLIST:/獲取所有記錄              /cursor = db.query("pe

11、rson", projection, selection, selectionArgs, null, null, sortOrder);              cursor = db.rawQuery("select * from person ", null);              break;&

12、#160;          case PERSON:/獲取單條記錄              long personid = ContentUris.parseId(uri);              String where = selecti

13、on!=null && !"".equals(selection.trim() ? selection+ " and personid="+ personid : "personid="+ personid;              cursor = db.query("person", projection, where, selectionArgs, null, n

14、ull, sortOrder);              break;           default:              /如果什么都沒有找到，就拋出一個異常。              throw new IllegalArgumentException("Uri IllegalArgument:"+ uri);