如何从其他类获取列索引(category._id或categorylang.Title)。
代码:
public Set<Category> getTopCategories() {
final List<Integer> loadedTopCats = new ArrayList<Integer>(0);
this.cursor = this.db.rawQuery(
"SELECT DISTINCT category.ParentID FROM category" +
" INNER JOIN categorylang ON category._id = categorylang.CategoryID" +
" INNER JOIN questiontable" +
" ON categorylang.CategoryID = questiontable.CategoryID" +
" WHERE category.ParentID != 0" +
" AND questiontable.QuestionID IS NOT NULL" ,
null);
while (this.cursor.moveToNext()) {
loadedTopCats.add(this.cursor.getInt(0));
}
this.cursor.close();
final StringBuilder allTopCatIds = new StringBuilder(loadedTopCats.size() * 2);
for (final Integer i : loadedTopCats) {
allTopCatIds.append(i + ",");
}
allTopCatIds.deleteCharAt(allTopCatIds.length() - 1);
final String query = "SELECT category._id, " +
"categorylang.Title, categorylang.Description, category.Position" +
" FROM category" +
" INNER JOIN categorylang" +
" ON category._id = categorylang.CategoryID" +
" WHERE category.ParentID = 0 AND category._id IN (" + allTopCatIds.toString() +
") ORDER BY category.Position DESC";
this.cursor = this.db.rawQuery(query, null);
SqlHelper.topCatList = new TreeSet<Category>();
SqlHelper.catMapping = new HashMap<Integer, Set<Category>>();
if (this.cursor.moveToFirst()) {
do {
SqlHelper.topCatList.add(new Category(this.cursor.getInt(0), this.cursor
.getString(1), "", this.cursor
.getString(2), this.cursor.getInt(3)));
SqlHelper.catMapping.put(this.cursor.getInt(0), null);
} while (this.cursor.moveToNext());
}
this.cursor.close();
return SqlHelper.topCatList;
}
我的意思是:this.cursor.getInt(0),this.cursor.getString(1)将在另一个类中使用 因此,我将在另一项活动中显示最高类别列表