这是我第一次使用内容提供商。 所以我有这个：
public class ContactsContentProvider extends ContentProvider {
private ContactsDatabaseHelper dbHelper;
private static final UriMatcher uriMatcher =
new UriMatcher(UriMatcher.NO_MATCH);
private static final int ONE_CONTACT = 1;
private static final int CONTACTS = 2;
private static final int CONTACT = 3;
static {
uriMatcher.addURI(ContactsDatabaseDescription.AUTHORITY,
Contact.TABLE_NAME + "/#", ONE_CONTACT);
uriMatcher.addURI(ContactsDatabaseDescription.AUTHORITY,
Contact.TABLE_NAME, CONTACTS);
uriMatcher.addURI(ContactsDatabaseDescription.AUTHORITY,
Contact.TABLE_NAME + "/*" , CONTACT);
}
@Override
public boolean onCreate() {
dbHelper = new ContactsDatabaseHelper(getContext());
return true;
}
@Override
public String getType(Uri uri) {
return null;
}
@Override
public Cursor query(Uri uri, String[] projection,
String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(Contact.TABLE_NAME);
switch (uriMatcher.match(uri)) {
case ONE_CONTACT:
queryBuilder.appendWhere(
Contact._ID + "=" + uri.getLastPathSegment());
break;
case CONTACTS:
break;
default:
throw new UnsupportedOperationException(
getContext().getString(R.string.invalid_query_uri) + uri);
}
Cursor cursor = queryBuilder.query(dbHelper.getReadableDatabase(),
projection, selection, selectionArgs, null, null, sortOrder);
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}
// insert a new contact in the database
@Override
public Uri insert(Uri uri, ContentValues values) {
Uri newContactUri = null;
switch (uriMatcher.match(uri)) {
case CONTACTS:
// insert the new contact--success yields new contact's row id
long rowId = dbHelper.getWritableDatabase().insert(
Contact.TABLE_NAME, null, values);
if (rowId > 0) {
newContactUri = Contact.buildContactUri(rowId);
getContext().getContentResolver().notifyChange(uri, null);
}
else
throw new SQLException(
getContext().getString(R.string.insert_failed) + uri);
break;
default:
throw new UnsupportedOperationException(
getContext().getString(R.string.invalid_insert_uri) + uri);
}
return newContactUri;
}
@Override
public int update(Uri uri, ContentValues values,
String selection, String[] selectionArgs) {
int numberOfRowsUpdated; // 1 if update successful; 0 otherwise
switch (uriMatcher.match(uri)) {
case ONE_CONTACT:
String id = uri.getLastPathSegment();
numberOfRowsUpdated = dbHelper.getWritableDatabase().update(
Contact.TABLE_NAME, values, Contact._ID + "=" + id,
selectionArgs);
break;
default:
throw new UnsupportedOperationException(
getContext().getString(R.string.invalid_update_uri) + uri);
}
if (numberOfRowsUpdated != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return numberOfRowsUpdated;
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
int numberOfRowsDeleted;
switch (uriMatcher.match(uri)) {
case ONE_CONTACT:
String id = uri.getLastPathSegment();
numberOfRowsDeleted = dbHelper.getWritableDatabase().delete(
Contact.TABLE_NAME, Contact._ID + "=" + id, selectionArgs);
break;
default:
throw new UnsupportedOperationException(
getContext().getString(R.string.invalid_delete_uri) + uri);
}
if (numberOfRowsDeleted != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return numberOfRowsDeleted;
}
}
我的数据库是
public class ContactsDatabaseDescription {
public static final String AUTHORITY =
"com.example.afran.bdcontacts.data";
private static final Uri BASE_CONTENT_URI =
Uri.parse("content://" + AUTHORITY);
public static final class Contact implements BaseColumns {
public static final String TABLE_NAME = "contacts"; // table's name
public static final Uri CONTENT_URI =
BASE_CONTENT_URI.buildUpon().appendPath(TABLE_NAME).build();
public static final String COLUMN_FIRST_NAME = "firstName";
public static final String COLUMN_LAST_NAME = "lastName";
public static final String COLUMN_EMAIL = "email";
public static final String COLUMN_TYPE = "type";
public static Uri buildContactUri(long id) {
return ContentUris.withAppendedId(CONTENT_URI, id);
}
}
}
在这个片段上我读了一个姓氏（搜索），我想找到联系人，我不知道如何
public class DetailFragment extends Fragment
implements LoaderManager.LoaderCallbacks<Cursor> {
public interface DetailFragmentListener {
void onContactDeleted();
void onEditContact(Uri contactUri);
}
private static final int CONTACT_LOADER = 0;
private DetailFragmentListener listener;
private Uri contactUri;
private TextView prenomTextView;
private TextView nomTextView;
private TextView emailTextView;
private TextView typeTextView;
@Override
public void onAttach(Context context) {
super.onAttach(context);
listener = (DetailFragmentListener) context;
}
@Override
public void onDetach() {
super.onDetach();
listener = null;
}
@Override
public View onCreateView(
LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
setHasOptionsMenu(true);
Bundle arguments = getArguments();
if (arguments != null)
contactUri = arguments.getParcelable(MainActivity.CONTACT_URI);
View view =
inflater.inflate(R.layout.fragment_detail, container, false);
prenomTextView = (TextView) view.findViewById(R.id.firstNameTextView);
nomTextView = (TextView) view.findViewById(R.id.lastNameTextView);
emailTextView = (TextView) view.findViewById(R.id.emailTextView);
typeTextView = (TextView) view.findViewById(R.id.typeTextView);
getLoaderManager().initLoader(CONTACT_LOADER, null, this);
return view;
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
inflater.inflate(R.menu.menu_main, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_edit:
listener.onEditContact(contactUri);
return true;
case R.id.action_delete:
deleteContact();
return true;
case R.id.action_search:
searchContact();
return true;
}
return super.onOptionsItemSelected(item);
}
private void searchContact() {
final EditText input = new EditText(getContext());
final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setTitle(R.string.menuitem_recherche);
builder.setMessage(R.string.label_lastName);
builder.setView(input);
builder.setPositiveButton(R.string.button_ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int whichButton) {
String value = input.getText().toString();
return;
}
});
builder.setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
return;
}
});
builder.create().show();
}
private void deleteContact() {
final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setTitle(R.string.confirm_title);
builder.setMessage(R.string.confirm_message);
builder.setPositiveButton(R.string.button_delete, new DialogInterface.OnClickListener() {
@Override
public void onClick(
DialogInterface dialog, int button) {
getActivity().getContentResolver().delete(
contactUri, null, null);
listener.onContactDeleted();
}
}
);
builder.setNegativeButton(R.string.button_cancel, null);
builder.create().show();
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
CursorLoader cursorLoader;
switch (id) {
case CONTACT_LOADER:
cursorLoader = new CursorLoader(getActivity(),
contactUri,
null,
null,
null,
null);
break;
default:
cursorLoader = null;
break;
}
return cursorLoader;
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
if (data != null && data.moveToFirst()) {
int firstIndex = data.getColumnIndex(ContactsDatabaseDescription.Contact.COLUMN_FIRST_NAME);
int lastIndex = data.getColumnIndex(ContactsDatabaseDescription.Contact.COLUMN_LAST_NAME);
int emailIndex = data.getColumnIndex(ContactsDatabaseDescription.Contact.COLUMN_EMAIL);
int typeIndex = data.getColumnIndex(ContactsDatabaseDescription.Contact.COLUMN_TYPE);
prenomTextView.setText(data.getString(firstIndex));
nomTextView.setText(data.getString(lastIndex));
emailTextView.setText(data.getString(emailIndex));
typeTextView.setText(data.getString(typeIndex));
}
}
@Override
public void onLoaderReset(Loader<Cursor> loader) { }
}
答案 0 :(得分：0)
搜索表格中任何列的匹配很简单。您只需要查询的contentUri，where和whereArgs参数。确保你的Uri指向整个桌子。假设您要匹配名为＆＃34; first_name＆＃34;的列。和＆＃34;姓氏＆＃34;使用名为firstName和surname的字符串。
String where = "first_name =? and surname =?";
String[] whereArgs = {firstName, surname};
您可以使用括号和＆＃34;和＆＃34;和＆＃34;或＆＃34;构建更复杂的查询。使用数字字段，您可以使用＆gt;和＆lt;您必须确保whereArgs具有与＆＃34;？＆＃34;
一样多的元素