Sending LinkedHashMap to intent

Question

I want send LinkedHashMap to another Intent. But I don't known what method for extras is allowable.

Bundle extras = getIntent().getExtras();
  LinkedHashMap<Integer, String[]> listItems = extras.get(LIST_TXT);

Answer 1

You cannot reliably send a LinkedHashMap as an Intent extra. When you call putExtra() with a LinkedHashMap, Android sees that the object implements the Map interface, so it serializes the name/value pairs into the extras Bundle in the Intent. When you want to extract it on the other side, what you get is a HashMap, not a LinkedHashMap. Unfortunately, this HashMap that you get has lost the ordering that was the reason you wanted to use a LinkedHashMap in the first place.

The only reliable way to do this is to convert the LinkedHashMap to an ordered array, put the array into the Intent, extract the array from the Intent on the receiving end, and then recreate the LinkedHashMap.

See my answer to this question for more gory details.