Parse a JSON array with multiple object types - flutter

Question

Let's say I have a JSON array like this:
"videos": [
{
"id": 25182,
"game": 115653,
"name": "Trailer",
"video_id": "BdA22Lh6Rwk"
},
27749,
{
"id": 29188,
"game": 115653,
"name": "A New Team and New Rivals in Pokémon Sword and Pokémon Shield! ⚔️🛡️",
"video_id": "ZBiTpi8ecTE"
}
]
Normally if the item's JSON format in videos is like videos[0] or videos[2] then I was able to parse it to Video like this:
json['videos']?.cast<Map<String, dynamic>>()?.map<Video>((f) {
return Video.fromJson(f);
})?.toList();
My Video class:
class Video {
int id;
int game;
String name;
String videoId;
Video({this.id, this.game, this.name, this.videoId});
Video.fromJson(Map<String, dynamic> json) {
id = json['id'];
game = json['game'];
name = json['name'];
videoId = json['video_id'];
}
Map<String, dynamic> toJson() {
final Map<String, dynamic> data = new Map<String, dynamic>();
data['id'] = this.id;
data['game'] = this.game;
data['name'] = this.name;
data['video_id'] = this.videoId;
return data;
}
}
But if something with the different structure like videos[1] is within the array then I ended up with Exception. How can I parse videos[1] to Video with video[1] as Video's id?

Answer 1

You have to know the different formats and figure out which one each entry is.
You can do that by checking the type of the entry: Is it an integer or a map?
Example:
List<Video> videosFromJson(List<Object> videoJson) {
var result = <Video>[];
for (int i = 0; i < videoJson.length; i++) {
var entry = videoJson[i];
if (entry is Map<String, dynamic>) {
result.add(Video.fromJson(entry));
} else if (entry is int) {
result.add(Video()..id = entry);
} else {
throw FormatException("Not a recognized video format", entry, i);
}
}
return result;
}