How to test multiple activities on Android

Question

Hi

Im trying to create some jUnit tests for my Activities. The main activity seems easy to test by extending ActivityInstrumentationTestCase2<Main> and when i click "Run..." the app and the tests are installed on the emulator and runs fine. I can see that the main activity is starting.

The problem is that I can't figure out what I need to do to test my second activity. This activity is an activity that is normally started from within the Main activity, but I was hoping i could test it like a "stand-alone" activity. The problem is that i just keep getting

Test run failed: java.lang.NullPointerException

when i try to start the test.

// CODE THAT WORKS

package net.myapp.android;

import android.test.ActivityInstrumentationTestCase2;
import android.widget.ImageView;

public class AboutActivityTest extends ActivityInstrumentationTestCase2<Main> {

    private Main mActivity;

    public AboutActivityTest() {
        super("net.myapp.android", Main.class);
    }

    @Override
    protected void setUp() throws Exception {
        super.setUp();
        mActivity = getActivity();
    }

    public void testPreConditions() {
        assertTrue(mActivity != null);
    }

    public void testSpinnerUI2() {
        ImageView mImageView = (ImageView) mActivity.findViewById(net.myapp.android.R.id.b1);
        assertTrue(mImageView != null);
    }
}

// CODE THAT DOES NOT WORK

package net.myapp.android;

    import android.test.ActivityInstrumentationTestCase2;
    import android.widget.ImageView;

    public class AboutActivityTest extends ActivityInstrumentationTestCase2<SubActivity> {

        private SubActivitym;

        public AboutActivityTest() {
            super("net.myapp.android", SubActivity.class);
        }

        @Override
        protected void setUp() throws Exception {
            super.setUp();
            mActivity = getActivity();
        }

        public void testPreConditions() {
            assertTrue(mActivity != null);
        }

        public void testSpinnerUI2() {
            ImageView mImageView = (ImageView) mActivity.findViewById(net.myapp.android.R.id.b1);
            assertTrue(mImageView != null);
        }
    }

The activities are defined in the AndroidManifest.xml like this:

    <activity android:name="net.myapp.android.Main" android:label="@string/app_name"
        android:launchMode="singleTop" android:screenOrientation="portrait"
        android:configChanges="keyboardHidden|orientation">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>

    </activity>


    <!-- SubActivity -->
    <activity android:name="net.myapp.android.SubActivity" android:label="@string/about"

So, the problem is when I'm trying to start the SubActivity test i get this error on the eclipse console:

[2010-09-13 14:01:58 - testAndroid] Collecting test information
[2010-09-13 14:02:00 - testAndroid] Sending test information to Eclipse
[2010-09-13 14:02:00 - testAndroid] Running tests...
[2010-09-13 14:02:03 - testAndroid] Test run failed: java.lang.NullPointerException
[2010-09-13 14:02:03 - testAndroid] Test run complete

Any ideas anyone?

UPDATE - RESOLVED:

It was an obvious mistake by me. The NullPointerException was coused by the onCreate method inside the SubActivity. The eclipse console didn't show that, I had to look at ddms/logcat.

I was trying to read out an extra parameter from the intent, but it was never set before startup. I had to use putExtra before i called getActivity :

Intent intent = new Intent();
intent.putExtra("ver","1.16");
setActivityIntent(intent);
mActivity = getActivity();