6
Tôi có một listView được điền bởi một con trỏ từ trình tải con trỏ và sử dụng nhà cung cấp nội dung. Tôi muốn sắp xếp listView để nó được sắp xếp ví dụ các mục gần đây nhất được thêm vào ở trên cùng của listView. ListView luôn xuất hiện theo cùng thứ tự và tôi không thể thay đổi thứ tự này.Thứ tự sắp xếp không hoạt động với listView và trình tải con trỏ
Tôi đã thử sử dụng thứ tự sắp xếp và thay đổi thứ tự và không có vấn đề gì được đặt vào danh sáchXem luôn hiển thị các mục ở cùng vị trí. Sử dụng thứ tự sắp xếp như thế này,
CursorLoader loader = new CursorLoader
(List.this, Database.CONTENT_URI, projection,
null, null, LocationsTable.TIME_STAMP + " ASC");
Tôi đã cố gắng sắp xếp theo các cột khác ngoài TIME_STAMP nhưng kết quả luôn giống nhau. thứ tự của các mục trong danh sách không bao giờ thay đổi. thậm chí thay đổi ASC thành DESC cũng không có hiệu lực.
Làm cách nào tôi có thể đặt thứ tự hoặc vị trí của các mục được hiển thị trong listView được điền bằng một con trỏAdapter?
một số mẫu mã hơn từ lớp listview
Từ phương pháp onCreate
adapter = new ViewAdapter(this, null, 0);
// sets array adapter to listview
listViewOne.setAdapter(adapter);
getLoaderManager().initLoader(LOADER_ID_ONE, null, this);
Ba phương thức callback của LoaderCallbacks<Cursor>
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
String projection[] = new String[]{LocationsTable._ID,
LocationsTable.LATITUDE, LocationsTable.LONGITUDE,
LocationsTable.LAND_ADDRESS, LocationsTable.LAST_NAME,
LocationsTable.FIRST_NAME, LocationsTable.LOCATION_IMAGE,
LocationsTable.TIME_STAMP };
CursorLoader loader = new CursorLoader
(List.this, Database.CONTENT_URI, projection, null, null,
LocationsTable.TIME_STAMP + " ASC");
return loader;
} // onCreateLoader
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
adapter.swapCursor(cursor);
} // onLoadFinished
@Override
public void onLoaderReset(Loader<Cursor> arg0) {
adapter.swapCursor(null);
} // onLoaderReset
Đây là chuỗi được sử dụng để tạo ra các bảng trong cơ sở dữ liệu mở rộng ContentProvider
private static final String SQL_QUERY_CREATE = "CREATE TABLE "
+ LocationsTable.TABLE_NAME + " (" + LocationsTable._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + LocationsTable.LATITUDE + " TEXT NOT NULL, "
+ LocationsTable.LONGITUDE + " TEXT NOT NULL, " + LocationsTable.LAND_ADDRESS + " TEXT, " + LocationsTable.LAST_NAME + " TEXT, "
+ LocationsTable.FIRST_NAME + " TEXT, " + LocationsTable.LAST_NAME_ALT + " TEXT, " + LocationsTable.FIRST_NAME_ALT + " TEXT, "
+ LocationsTable.CONTACT_ADDRESS + " TEXT, " + LocationsTable.PHONE_NUMBER + " TEXT, " + LocationsTable.MOBILE_NUMBER + " TEXT, "
+ LocationsTable.EMAIL + " TEXT, " + LocationsTable.LOCATION_IMAGE + " TEXT, " + LocationsTable.TIME_STAMP_IMAGE + " INTEGER, "
+ LocationsTable.TIME_STAMP + " INTEGER " + ");";
Các bộ chuyển đổi con trỏ lớp
public class ViewAdapter extends CursorAdapter {
LayoutInflater inflater;
LatAndLngString latAndLng;
public ViewAdapter(Context context, Cursor cursor, int b) {
super(context, cursor, b);
inflater = LayoutInflater.from(context);
} // ViewAdapter constructor
@Override
public void bindView(View view, final Context context, Cursor cursor) {
TextView textViewOne = (TextView) view.findViewById(R.id.textView1); // address
TextView textViewTwo = (TextView) view.findViewById(R.id.textView2); // last name
TextView textViewThree = (TextView) view.findViewById(R.id.textView3); // first name
final Button buttonOne = (Button) view.findViewById(R.id.button1);
final ImageView imageViewOne = (ImageView) view.findViewById(R.id.imageView1);
final ImageView imageViewTwo = (ImageView) view.findViewById(R.id.imageView2);
textViewOne.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.LAND_ADDRESS)));
textViewTwo.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.LAST_NAME)));
textViewThree.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.FIRST_NAME)));
String latitude = cursor.getString(cursor.getColumnIndex(LocationsTable.LATITUDE));
String longitude = cursor.getString(cursor.getColumnIndex(LocationsTable.LONGITUDE));
String imagePath = cursor.getString(cursor.getColumnIndex(LocationsTable.LOCATION_IMAGE));
long timeStampImage = cursor.getLong(cursor.getColumnIndex(LocationsTable.TIME_STAMP));
if(imagePath != null){
int widthInDP = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 80, getResources().getDisplayMetrics());
int heightInDP = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 50, getResources().getDisplayMetrics());
Bitmap sizedBitmap = ImageUtil.createReducedBitmap(imagePath, widthInDP, heightInDP);
imageViewTwo.setImageBitmap(sizedBitmap);
}
textViewOne.setMaxLines(1);
textViewTwo.setMaxLines(2);
textViewThree.setMaxLines(3);
final LatAndLngString latAndLng = new LatAndLngString(latitude, longitude);
buttonOne.setTag(latAndLng);
imageViewOne.setTag(latAndLng);
imageViewTwo.setTag(latAndLng);
// go to register page to edit fields
buttonOne.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
((Button) view).setAlpha(0.3f);
LatAndLngString latAndLngRow = (LatAndLngString) buttonOne.getTag();
Intent intent = new Intent(List.this, Register.class);
intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
intent.putExtra("origin", 1);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
List.this.startActivity(intent);
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
((Button) view).setAlpha(1.0f);
return true;
}
return false;
}
});
// go to map page to display map
imageViewOne.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
((ImageView) view).setAlpha(0.3f);
LatAndLngString latAndLngRow = (LatAndLngString) buttonOne.getTag();
Intent intent = new Intent(List.this, Map.class);
intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.putExtra("showMarker", true);
List.this.startActivity(intent);
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
((ImageView) view).setAlpha(1.0f);
return true;
}
return false;
}
});
// set image for button
imageViewTwo.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
((ImageView) view).setAlpha(0.3f);
LatAndLngString latAndLngRow = (LatAndLngString) view.getTag();
Intent intent = new Intent(List.this, ImageSelector.class);
intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
List.this.startActivity(intent);
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
((ImageView) view).setAlpha(1.0f);
return true;
}
return false;
}
});
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
return inflater.inflate(R.layout.listview_row, parent, false);
}
}
NỘI DUNG CUNG CẤP CLASS đầy đủ mã ở đây
// application package name
// import statements
public class Database extends ContentProvider {
private static final UriMatcher sUriMatcher;
private static final int LOCATIONS_ALL = 1;
private static final int LOCATIONS_ONE = 2;
public static final String AUTHORITY = "com.xxx.realestatelocator.Locations";
public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/locations");
public static final String DATABASE_NAME = "locations.db";
public static final int DATABASE_VERSION = 1;
public static final String CONTENT_TYPE_NOTES_ALL = "vnd.android.cursor.dir/vnd.realestate.locations";
public static final String CONTENT_TYPE_NOTES_ONE = "vnd.android.cursor.item/vnd.realestate.locations";
static {
sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
sUriMatcher.addURI(AUTHORITY, "locations", LOCATIONS_ALL);
sUriMatcher.addURI(AUTHORITY, "locations/#", LOCATIONS_ONE);
}
// Map table columns
private static final HashMap<String, String> sNotesColumnProjectionMap;
private DatabaseHelper mDbHelper;
static {
sNotesColumnProjectionMap = new HashMap<String, String>();
sNotesColumnProjectionMap.put(LocationsTable._ID, LocationsTable._ID);
sNotesColumnProjectionMap.put(LocationsTable.LATITUDE, LocationsTable.LATITUDE);
sNotesColumnProjectionMap.put(LocationsTable.LONGITUDE, LocationsTable.LONGITUDE);
sNotesColumnProjectionMap.put(LocationsTable.LAND_ADDRESS, LocationsTable.LAND_ADDRESS);
sNotesColumnProjectionMap.put(LocationsTable.LAST_NAME, LocationsTable.LAST_NAME);
sNotesColumnProjectionMap.put(LocationsTable.FIRST_NAME, LocationsTable.FIRST_NAME);
sNotesColumnProjectionMap.put(LocationsTable.LAST_NAME_ALT, LocationsTable.LAST_NAME_ALT);
sNotesColumnProjectionMap.put(LocationsTable.FIRST_NAME_ALT, LocationsTable.FIRST_NAME_ALT);
sNotesColumnProjectionMap.put(LocationsTable.CONTACT_ADDRESS, LocationsTable.CONTACT_ADDRESS);
sNotesColumnProjectionMap.put(LocationsTable.PHONE_NUMBER, LocationsTable.PHONE_NUMBER);
sNotesColumnProjectionMap.put(LocationsTable.MOBILE_NUMBER, LocationsTable.MOBILE_NUMBER);
sNotesColumnProjectionMap.put(LocationsTable.EMAIL, LocationsTable.EMAIL);
sNotesColumnProjectionMap.put(LocationsTable.LOCATION_IMAGE, LocationsTable.LOCATION_IMAGE);
sNotesColumnProjectionMap.put(LocationsTable.TIME_STAMP_IMAGE, LocationsTable.TIME_STAMP_IMAGE);
sNotesColumnProjectionMap.put(LocationsTable.TIME_STAMP, LocationsTable.TIME_STAMP);
}
public class LocationsTable implements BaseColumns {
public static final String TABLE_NAME = "tbl_locations";
public static final String _ID = "_id";
public static final String LATITUDE = "latitude";
public static final String LONGITUDE = "longitude";
public static final String LAND_ADDRESS = "land_address";
public static final String LAST_NAME = "last_name";
public static final String FIRST_NAME = "first_name";
public static final String LAST_NAME_ALT = "last_name_alt";
public static final String FIRST_NAME_ALT = "first_name_alt";
public static final String CONTACT_ADDRESS = "contact_address";
public static final String PHONE_NUMBER = "phone_number";
public static final String MOBILE_NUMBER = "mobile_number";
public static final String EMAIL = "email_address";
public static final String LOCATION_IMAGE = "location_image";
public static final String TIME_STAMP_IMAGE = "time_stamp_image";
public static final String TIME_STAMP = "time_stamp";
} // LocationsTable inner class
private static class DatabaseHelper extends SQLiteOpenHelper {
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
private static final String SQL_QUERY_CREATE = "CREATE TABLE "
+ LocationsTable.TABLE_NAME + " (" + LocationsTable._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + LocationsTable.LATITUDE + " TEXT NOT NULL, "
+ LocationsTable.LONGITUDE + " TEXT NOT NULL, " + LocationsTable.LAND_ADDRESS + " TEXT, " + LocationsTable.LAST_NAME + " TEXT, "
+ LocationsTable.FIRST_NAME + " TEXT, " + LocationsTable.LAST_NAME_ALT + " TEXT, " + LocationsTable.FIRST_NAME_ALT + " TEXT, "
+ LocationsTable.CONTACT_ADDRESS + " TEXT, " + LocationsTable.PHONE_NUMBER + " TEXT, " + LocationsTable.MOBILE_NUMBER + " TEXT, "
+ LocationsTable.EMAIL + " TEXT, " + LocationsTable.LOCATION_IMAGE + " TEXT, " + LocationsTable.TIME_STAMP_IMAGE + " INTEGER, "
+ LocationsTable.TIME_STAMP + " INTEGER " + ");";
private static final String SQL_QUERY_DROP = "DROP TABLE IF EXISTS " + LocationsTable.TABLE_NAME + ";";
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(SQL_QUERY_CREATE);
} // onCreate
@Override
public void onUpgrade(SQLiteDatabase db, int oldVer, int newVer) {
db.execSQL(SQL_QUERY_DROP);
onCreate(db);
} // onUpgrade
} // DatabaseHelper inner class
@Override
public boolean onCreate() {
if(mDbHelper == null) {
mDbHelper = new DatabaseHelper(getContext());
}
return false;
}
@Override
public String getType(Uri arg0) {
return null;
} // getType
// insert one new row, full row
@Override
public Uri insert(Uri uri, ContentValues values) {
if (sUriMatcher.match(uri) != LOCATIONS_ALL) {
throw new IllegalArgumentException(" Unknown URI: " + uri);
}
SQLiteDatabase db = mDbHelper.getWritableDatabase();
long rowId = db.insert(LocationsTable.TABLE_NAME, null, values);
if (rowId > 0) {
Uri notesUri = ContentUris.withAppendedId(CONTENT_URI, rowId);
getContext().getContentResolver().notifyChange(notesUri, null);
return notesUri;
}
throw new IllegalArgumentException("<Illegal>Unknown URI: " + uri);
} // insert
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
switch (sUriMatcher.match(uri)) {
case LOCATIONS_ALL:
builder.setTables(LocationsTable.TABLE_NAME);
builder.setProjectionMap(sNotesColumnProjectionMap);
break;
case LOCATIONS_ONE:
builder.setTables(LocationsTable.TABLE_NAME);
builder.setProjectionMap(sNotesColumnProjectionMap);
builder.appendWhere(LocationsTable._ID + " = " + uri.getLastPathSegment());
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
SQLiteDatabase db = mDbHelper.getReadableDatabase();
Cursor queryCursor = builder.query(db, projection, selection, selectionArgs, null, null, null);
queryCursor.setNotificationUri(getContext().getContentResolver(), uri);
return queryCursor;
} // query
@Override
public int update(Uri uri, ContentValues values, String where, String[] whereArgs) {
SQLiteDatabase db = mDbHelper.getWritableDatabase();
int count = 0;
switch (sUriMatcher.match(uri)) {
case LOCATIONS_ALL:
count = db.update(LocationsTable.TABLE_NAME, values, where, whereArgs);
break;
case LOCATIONS_ONE:
String rowId = uri.getLastPathSegment();
count = db.update(LocationsTable.TABLE_NAME, values, LocationsTable._ID
+ " = " + rowId + (!TextUtils.isEmpty(where) ? " AND (" + ")" : ""), whereArgs);
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return count;
} // update
// delete
@Override
public int delete(Uri uri, String where, String[] whereArgs) {
SQLiteDatabase db = mDbHelper.getWritableDatabase();
int count = 0;
switch (sUriMatcher.match(uri)) {
case LOCATIONS_ALL:
count = db.delete(LocationsTable.TABLE_NAME, where, whereArgs);
break;
case LOCATIONS_ONE:
String rowId = uri.getPathSegments().get(1);
count = db.delete(LocationsTable.TABLE_NAME, LocationsTable._ID + " = "
+ rowId + (!TextUtils.isEmpty(where) ? " AND (" + where + ")" : ""), whereArgs);
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return count;
} // delete
} // Database
Chỉ trong trường hợp - để có được hầu hết các mặt hàng gần đây sử dụng 'DESC' thay vì' ASC' –
Ngoài ra, xin vui lòng cung cấp mã của 'bạn ContentProvider' –
tôi vừa thêm mã cho lớp nhà cung cấp nội dung, Cơ sở dữ liệu mở rộng ContentProvider – Kevik