Compdigitec Labs

« | Home | »

Techniques for testing Android fragments

By admin | March 4, 2013

How to test a fragment-based Android application:

Preferably test in the “don’t keep activities” mode, as this will root out a ton of bugs related to the Android lifecycle – i.e. when Android decides to kill an old activity of yours.

Case Study:

User complaint: http://forum.videolan.org/viewtopic.php?f=35&t=108743

The story so far… old versions of the VLC for Android beta, up to 0.0.10, suffer from a bug, where trying to delete something in another fragment causes the other (non-visible) fragment to receive the onContextItemSelected() call. After setting user visibility hints for that bug, a series of fragment related bugs appeared, mostly involving IllegalStateException in android.support.v4.app.FragmentManager because of duplicate fragments being added.

The problems were caused when Android decided to kill unused background activities. The interface code would try to recreate and re-add() fragments, even though Android had automatically recreated them via “android.support.fragments” in the onCreate() bundle. This would manifest after opening another activity, shutting the screen off, or having a system popup appear.

The solution was to keep better track of currently-added fragments, as member variables of the main activity may not necessarily be kept after the activity was hidden. To solve the problem, a check was implemented in onRestoreFragments() to ‘recall’ fragments that were already added. This fixed the problem permanently.

The moral of the story: watch and manage fragments very carefully in order to prevent problems.

If you found this article helpful or interesting, please help Compdigitec spread the word. Don’t forget to subscribe to Compdigitec Labs for more useful and interesting articles!

Topics: Mobile | 9 Comments »

9 Responses to “Techniques for testing Android fragments”

  1. ไก่ตัน Says:
    November 2nd, 2024 at 20:53

    … [Trackback]

    […] Read More on that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  2. ตู้เชื่อม Says:
    November 9th, 2024 at 03:35

    … [Trackback]

    […] Find More on to that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  3. Mpoker Says:
    November 17th, 2024 at 21:50

    … [Trackback]

    […] Info on that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  4. ทางเข้าpg Says:
    November 22nd, 2024 at 06:44

    … [Trackback]

    […] Information to that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  5. สอนสัก Says:
    December 1st, 2024 at 23:24

    … [Trackback]

    […] Here you will find 64851 additional Info on that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  6. โอลี่แฟน Says:
    December 3rd, 2024 at 01:01

    … [Trackback]

    […] Read More Info here on that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  7. ปั้มคนดูไลฟ์สด Says:
    December 9th, 2024 at 22:32

    … [Trackback]

    […] Read More on to that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  8. lucabet Says:
    December 15th, 2024 at 21:46

    … [Trackback]

    […] Read More Info here on that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

  9. PG SLOT เกมยอดฮิตแตกง่าย Says:
    December 19th, 2024 at 00:06

    … [Trackback]

    […] Information to that Topic: compdigitec.com/labs/2013/03/04/techniques-for-testing-android-fragments/ […]

Comments