Exception java.lang.RuntimeException: Unable to start activity ComponentInfo{com.memorygame/com.memorygame.MainActivity}: java.lang.NullPointerException: Attempt to read from field 'com.memorygame.model.BoardConfiguration com.memorygame.model.Game.boardConfiguration' on a null object reference

android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2695) android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2769) android.app.ActivityThread.handleRelaunchActivity (ActivityThread.java:4378) android.app.ActivityThread.access$1000 (ActivityThread.java:177) android.app.ActivityThread$H.handleMessage (ActivityThread.java:1436) android.os.Handler.dispatchMessage (Handler.java:102) android.os.Looper.loop (Looper.java:135) android.app.ActivityThread.main (ActivityThread.java:5910) java.lang.reflect.Method.invoke (Method.java) java.lang.reflect.Method.invoke (Method.java:372) com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1405) com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1200) arrow_drop_down Caused by java.lang.NullPointerException: Attempt to read from field 'com.memorygame.model.BoardConfiguration com.memorygame.model.Game.boardConfiguration' on a null object reference com.memorygame.fragments.GameFragment.buildBoard (GameFragment.java:76) com.memorygame.fragments.GameFragment.onCreateView (GameFragment.java:48) android.support.v4.app.Fragment.performCreateView (Fragment.java:2354) android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1419) android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState (FragmentManager.java:1740) android.support.v4.app.FragmentManagerImpl.moveToState (FragmentManager.java:1809) android.support.v4.app.FragmentManagerImpl.dispatchStateChange (FragmentManager.java:3217) android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated (FragmentManager.java:3171) android.support.v4.app.FragmentController.dispatchActivityCreated (FragmentController.java:192) android.support.v4.app.FragmentActivity.onStart (FragmentActivity.java:560) android.app.Instrumentation.callActivityOnStart (Instrumentation.java:1248) android.app.Activity.performStart (Activity.java:6213) android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2658) android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2769) android.app.ActivityThread.handleRelaunchActivity (ActivityThread.java:4378) android.app.ActivityThread.access$1000 (ActivityThread.java:177) android.app.ActivityThread$H.handleMessage (ActivityThread.java:1436) android.os.Handler.dispatchMessage (Handler.java:102) android.os.Looper.loop (Looper.java:135) android.app.ActivityThread.main (ActivityThread.java:5910) java.lang.reflect.Method.invoke (Method.java) java.lang.reflect.Method.invoke (Method.java:372) com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1405) com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1200)

So as I promised, here is the best times addition. This is how the app works on my device after the changes right now :

Important : If you are satisfied with my Pull Request, please accept it within the next 24 hours, as I need to know if my changes have been merged to get some bonus points for a college project I have on Friday. Cheers!

Hello!

Great job with the game, looks nice and simple. I have on suggestion to make, regarding the difficulty selection screen. How would you like it that the best time for each difficulty and stage would appear under the stars label? Stars don't make it completely understandable how well someone has performed in each stage. However time does. So this is my suggestion on how it would look.

Keep in mind that this is just a quick edit to demonstrate my idea and it is not the final view of the screen. Let me know what you think.

Thank you, Dimitris

I run this game in genymotion, Samsung Galaxy S4 API 19. the game stop after I click play.

I will try to add screenshot later. or test in a real device

Update:

I tried with API 23 and it is working

main changes:

1. background music has been fixed.
2. three or more cards can not be displayed.
3. bugs in the main menu about opening more than one menu has been fixed.
4. app doesn't crash after clicking many times on next level button in win popup.

Currently there is no back button in the navigation while the user selects the level or any of the dialogs. This PR adds this button with the proper functionality in order to improve the user experience.

https://user-images.githubusercontent.com/49449095/119278672-594fa580-bbec-11eb-92e2-59afa0104c8a.mp4

Here is a video with the proper testing

when you click on play button several times fast in main menu, more than one theme select menu appears and when you click on back button it again shows theme select menu instead of main menu.

This is an update to the README to make it more clear as to what this project is about and how others can contribute to it. It also functions to make the README more professional as well as remove the first person tense from the README (i.e. "We") and corrects the grammar.