Failed to retrieve ArrayList from a separate class

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Initialization of an ArrayList in one line 32 answers

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You are creating new object of DataHandling in the activity. So it will not be the same object that you had previously used and which has data in it.

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First :- If your ArrayList<Event> is empty and if you get 0th index element then you'll get NullPointerException while Executing this line :- dh.getEventArray().get(0).getName() so it is replaced by null.getName() which will break.

So if you want to get index basis Element form collection firsat checkl whether the Collection is empty or not. Like this:-

    //if the ArrayList is not Empty then only iterate over it.
    if(!dh.getEventArray().isEmpty())
    {
        textView.setText(dh.getEventArray().get(0).getName());
    }

Second:- Check the logic for adding the Event In ArrayList<Event> .

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Your method is called getArray() , yet you're invoking getEventArray() . Maybe it is the reason.

EDIT: Now that your message is edit we have something to work on.

DataHandaling dh = new DataHandaling();

This is a new DataHandaling object, and never in your code you're updating him. So I guess that its ArrayList is empty by default.

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