我有一个listView,它由游标加载器中的游标填充,并使用内容提供程序.我想对listView进行排序,以便安排它例如最新的项目添加在listView的顶部. listView始终以相同的顺序出现,我无法更改此顺序.
我尝试使用排序顺序并更改它,无论它设置为什么,listView始终显示相同位置的项目.使用这样的排序顺序,
CursorLoader loader = new CursorLoader (List.this,Database.CONTENT_URI,projection,null,LocationsTable.TIME_STAMP + " ASC");
我试图按TIME_STAMP之外的其他列进行排序,但结果始终相同.列表中项目的顺序永远不会改变.甚至将ASC更改为DESC也没有效果.
如何设置使用cursorAdapter填充的listView中显示的项目的顺序或位置?
listview类中的一些代码示例
来自onCreate方法
adapter = new ViewAdapter(this,0); // sets array adapter to listview listViewOne.setAdapter(adapter); getLoaderManager().initLoader(LOADER_ID_ONE,this);
LoaderCallbacks的三个回调方法< 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,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
这是用于在数据库中创建表的字符串扩展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 " + ");";
游标适配器类
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.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,ViewGroup parent) { return inflater.inflate(R.layout.listview_row,parent,false); } }
CONTENT PROVIDER CLASS完整代码
// 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,DATABASE_VERSION); } private static final String sql_QUERY_CREATE = "CREATE TABLE " + LocationsTable.TABLE_NAME + " (" + LocationsTable._ID + " INTEGER PRIMARY KEY AUTOINCREMENT," + 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,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,selection,selectionArgs,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,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[] whereArgs) { sqliteDatabase db = mDbHelper.getWritableDatabase(); int count = 0; switch (sUriMatcher.match(uri)) { case LOCATIONS_ALL: count = db.delete(LocationsTable.TABLE_NAME,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