Android(安卓)内容提供者ContentProvider

public class PersonDBProvider extends ContentProvider {    private PersonDBHelper mDbHelper;    //定义匹配工具，如果不匹配返回-1;    private static UriMatcher mMatcher = new UriMatcher(UriMatcher.NO_MATCH);    private static final String AUTHORITIES = "com.android.basic.provider.PersonDBProvider";    private static final int INSERT = 0;    private static final int DELETE = 1;    private static final int UPDATE = 2;    private static final int QUERY = 3;    private static Uri PERSONS_DB_URI = Uri.parse("content://" + AUTHORITIES);    private static final String TABLE = "person";    static{        mMatcher.addURI(AUTHORITIES, "insert", INSERT);        mMatcher.addURI(AUTHORITIES, "delete", DELETE);        mMatcher.addURI(AUTHORITIES, "update", UPDATE);        mMatcher.addURI(AUTHORITIES, "query", QUERY);    }    @Override    public boolean onCreate() {        mDbHelper = new PersonDBHelper(getContext());        return false;    }    @Override    public Cursor query(Uri uri, String[] projection, String selection,            String[] selectionArgs, String sortOrder) {        if (mMatcher.match(uri)==QUERY) {            SQLiteDatabase db = mDbHelper.getReadableDatabase();            return db.query(TABLE, projection, selection, selectionArgs, null, null, sortOrder);        } else {            throw new IllegalArgumentException("路径错误!");        }    }    @Override    public String getType(Uri uri) {        // TODO Auto-generated method stub        return null;    }    @Override    public Uri insert(Uri uri, ContentValues values) {        if (mMatcher.match(uri) == INSERT) {            Logger.i("tag", "uri==" + uri.toString());            Logger.i("tag", "getAuthority==" + uri.getAuthority());            SQLiteDatabase db = mDbHelper.getWritableDatabase();            long index = db.insert(TABLE, null, values);            getContext().getContentResolver().notifyChange(PERSONS_DB_URI, null);            return Uri.withAppendedPath(uri, index+"");        }else {            throw new IllegalArgumentException("路径错误!");        }    }    @Override    public int delete(Uri uri, String selection, String[] selectionArgs) {        if (mMatcher.match(uri) == DELETE) {            SQLiteDatabase db = mDbHelper.getWritableDatabase();            getContext().getContentResolver().notifyChange(PERSONS_DB_URI, null);            return db.delete(TABLE, selection, selectionArgs);        }else {            throw new IllegalArgumentException("路径错误!");        }    }    @Override    public int update(Uri uri, ContentValues values, String selection,            String[] selectionArgs) {        if (mMatcher.match(uri) == UPDATE) {            SQLiteDatabase db = mDbHelper.getWritableDatabase();            getContext().getContentResolver().notifyChange(PERSONS_DB_URI, null);            return db.update(TABLE, values, selection, selectionArgs);        }else {            throw new IllegalArgumentException("路径错误!");        }    }}

实现

public class ProviderActivity extends Activity {    private static final Uri QUERY_URI = Uri.parse("content://com.android.basic.provider.PersonDBProvider/query");    private static final Uri ADD_URI = Uri.parse("content://com.android.basic.provider.PersonDBProvider/add");    private static final Uri DELETE_URI = Uri.parse("content://com.android.basic.provider.PersonDBProvider/delete");    private static final Uri UPDATE_URI = Uri.parse("content://com.android.basic.provider.PersonDBProvider/update");    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_provider);    }    public void query(View view){        Cursor cursor = getContentResolver().query(QUERY_URI, null, null, null, null);        while(cursor.moveToNext()){            String name = cursor.getString(cursor.getColumnIndex("name"));            String number = cursor.getString(cursor.getColumnIndex("number"));            Logger.i("tag", "name==" + name);            Logger.i("tag", "number==" + number);        }    }    public void add(View view){        for (int i = 0; i < 10; i++) {            ContentValues values = new ContentValues();            values.put("name", "tom"+i);            values.put("number", "20"+i);            Uri uri = getContentResolver().insert(ADD_URI, values);        }    }    public void delete(View view){        ContentValues values = new ContentValues();        values.put("name", "tom");        values.put("number", "20");        int delete = getContentResolver().delete(DELETE_URI, "_id = ?", new String[]{"1"});        Logger.i("tag", "delete==" + delete);    }    public void update(View view){        ContentValues values = new ContentValues();        values.put("name", "jack");        values.put("number", "50");        getContentResolver().update(UPDATE_URI, values, "_id = ?", new String[]{"1"});    }}

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