sergioserra
commented
6 years ago The problem is that when Android serializes the Bundle when saving or restoring the state, it only supports a subset of types: Integer, Long, String, Map, Bundle, List.
If you serialize an ArrayList of LinkedHashMap it will be restored as List and Map. This is problematic if using LinkedHashMap because you loose the element ordering.
See: https://stackoverflow.com/questions/12300886/linkedlist-put-into-intent-extra-gets-recast-to-arraylist-when-retrieving-in-nex/12305459#12305459 for more details
You can use a custom bundler to avoid the problem:
Create a custom bundler:
public class LinkedHashmapBundler implements Bundler<LinkedHashMap> {
@Override
public void put(String s, LinkedHashMap val, Bundle bundle) {
bundle.putSerializable(s, new Wrapper<>(val));
}
@SuppressWarnings("unchecked")
@Override
public LinkedHashMap get(String s, Bundle bundle) {
return ((Wrapper<LinkedHashMap>) bundle.getSerializable(s)).get();
}
}
public class Wrapper<T extends Serializable> implements Serializable {
private T wrapped;
Wrapper(T wrapped) {
this.wrapped = wrapped;
}
public T get() {
return wrapped;
}
} Use it like this:
@State(LinkedHashmapBundler.class) LinkedHasMap map
oradkovsky
I get an error "java.lang.ClassCastException" when restoring activity.
@State LinkedHashMap<Double, String[]> dropsMap;How can this be avoided?