Question

I have and Intent and I pass, from the MainActivity, two ArrayLists of Parcelables to a “FormActivity”, that receives the ArrayLists perfeclty (using startActivityForResult), returns perfectly the data gathered throught the form.

The problem is that, if I click the button to open again the FormActivity, the two ArrayLists are not sent again, and I get a NullPointerException.

Have anyone ever seen this?

Thank you.

MainActivity code:

 public void insertProductButtonClicked(View view){
    Intent addProductIntent = new Intent(getBaseContext(), AddProductActivity.class);
    addProductIntent.removeExtra("consumers");
    addProductIntent.removeExtra("products");
    addProductIntent.putParcelableArrayListExtra("consumers", consumers);
    addProductIntent.putParcelableArrayListExtra("products", products);
    startActivityForResult(addProductIntent, MyActivities.ACTIVITY_ADD_PRODUCT);
}

AddProductActivity code (“FormActivity”):

    Intent intent = new Intent();
intent.putExtra("productName", productNameEditText.getText().toString());
intent.putExtra("productPrice", Double.valueOf(productPriceEditText.getText().toString()));

SparseBooleanArray checkedItems = consumersListView.getCheckedItemPositions();
ArrayList<Integer> consumersToAdd = new ArrayList<Integer>();
for (int i = 0; i < consumers.size(); i++) {
    if (checkedItems.get(i)){
        consumersToAdd.add(consumers.get(i).getId());
    }
}

intent.putIntegerArrayListExtra("productConsumers", consumersToAdd);
setResult(Activity.RESULT_OK, intent);
finish();

Answer 1

You can declare your ArrayList as a static, check below…

public static ArrayList<String> array = new ArrayList<String>(); 

By doing this you can access your ArrayList from anywhere by type

activity_name.array;

where activity_name is the activity or class in which you declare the static ArrayList.

Good luck.