Issue
I’m trying to read the bookmarked items in my app on page reload. The code queries the list of items previously bookmarked but unable to access the particular bookmarked index. What am I missing to map the objects correctly? please help!
Future<List<Map<String, dynamic>>>_readfav() async {
DatabaseHelper helper = DatabaseHelper.instance;
List<Bookmark> savedbk = [];
final favs = await helper.queryAllRows();
print(favs); // returns a map of favorite objects
favs.forEach((row) => savedbk.add(Bookmark()));
print(savedbk); // returns Instances of Bookmark
print( savedbk[0].Ayah.toString()); // returns null-- this is the problem
return favs;
}
model class
class Bookmark{
int id;
int Surah;
int Ayah;
int Juz;
Bookmark();
Bookmark.fromMap(Map<String, dynamic> map) {
id = map[columnId];
Surah = map[columnSurah];
Ayah = map[columnAyah];
Juz = map[columnJuz];
}
Map<String, dynamic> toMap() {
var map = <String, dynamic>{
columnSurah: Surah ,
columnAyah: Ayah,
columnJuz : Juz
};
if (id != null) {
map[columnId] = id;
}
return map;
}
}
Solution
Maybe the problem comes from the fact that you are not using row
Future<List<Map<String, dynamic>>>_readfav() async {
DatabaseHelper helper = DatabaseHelper.instance;
List<Bookmark> savedbk = [];
final favs = await helper.queryAllRows();
favs.forEach((row) => savedbk.add(Bookmark())); <-- here
print( savedbk[0].Ayah.toString());
return favs;
}
Doing favs.forEach((row) => savedbk.add(Bookmark())); will only create a list of empty Bookmark instances.
Maybe you should use favs.forEach((row) => savedbk.add(Bookmark.fromMap(row))); based on your constructor
Answered By – Quentin Klein
Answer Checked By – Timothy Miller (FlutterFixes Admin)