Question

I have extensive use of ArrayAdapter in my app because most Activities are holding a ListView and I need some custom stuff in them.

I took a look at the test classes in the android developer documentation but wasn’t able to find some examples or a proper testclass…

1) Are there any best practices for (unit)-testing ArrayAdapter in Android?

2) May I have chosen the wrong approach (with the adapters) and killed testability this way?

Answer 1

You can write the test extending AndroidTestCase It will looks something like this:

public class ContactsAdapterTest extends AndroidTestCase {
    private ContactsAdapter mAdapter;

    private Contact mJohn;
    private Contact mJane;

    public ContactsAdapterTest() {
        super();
    }

    protected void setUp() throws Exception {
        super.setUp();
        ArrayList<Contact> data = new ArrayList<Contact>();

        mJohn = new Contact("John", "[phone]", "uri");
        mJane = new Contact("Jane", "[phone]", "uri");
        data.add(mJohn);
        data.add(mJane);
        mAdapter = new ContactsAdapter(getContext(), data);
    }


    public void testGetItem() {
        assertEquals("John was expected.", mJohn.getName(),
                ((Contact) mAdapter.getItem(0)).getName());
    }

    public void testGetItemId() {
        assertEquals("Wrong ID.", 0, mAdapter.getItemId(0));
    }

    public void testGetCount() {
        assertEquals("Contacts amount incorrect.", 2, mAdapter.getCount());
    }

    // I have 3 views on my adapter, name, number and photo
    public void testGetView() {
        View view = mAdapter.getView(0, null, null);

        TextView name = (TextView) view
                .findViewById(R.id.text_contact_name);

        TextView number = (TextView) view
                .findViewById(R.id.text_contact_number);

        ImageView photo = (ImageView) view
                .findViewById(R.id.image_contact_photo);

        //On this part you will have to test it with your own views/data
        assertNotNull("View is null. ", view);
        assertNotNull("Name TextView is null. ", name);
        assertNotNull("Number TextView is null. ", number);
        assertNotNull("Photo ImageView is null. ", photo);

        assertEquals("Names doesn't match.", mJohn.getName(), name.getText());
        assertEquals("Numbers doesn't match.", mJohn.getNumber(),
                number.getText());
    }
}

Probably you will have to test getView several times with different arguments, to test all scenarios.