Fix NullPointerException in PlaylistEditCtrl

[Borewit]

Changes:

• Remove constructor in PlaylistEditCtrl without passing callback to main GUI window.
• Abstracted callbacks to main GUI window to interface IListFixGui.

Should resolve NullPointerException reported in #64 (comment)

java.util.concurrent.ExecutionException: java.lang.NullPointerException: Cannot invoke "listfix.view.GUIScreen.getMediaLibrary()" because "this.mainWindow" is null
	at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:?]
	at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:?]
	at javax.swing.SwingWorker.get(Unknown Source) ~[?:?]
	at listfix.view.controls.PlaylistEditCtrl$3.done(PlaylistEditCtrl.java:294) ~[listFix.exe:2.5.1-19]

[Borewit]

Build: listFix_2.5.1-PR89-26.exe

@touwys, can you test this version?

Please delete your log files (.listFix()\logs\logs\rollingfile.log), before running / testing this version, and focus on the following:

1. Is the NullPointerException (Cannot invoke "listfix.view.GUIScreen.getMediaLibrary()") resolved?
2. Does PR (represented by this build) break something new?
3. 🙏 Does it resolve Double printed tab pane headings of the playlist editors #55 ?

[touwys]

Build: listFix_2.5.1-PR89-26

Log-file was cleared before installation commenced:

• Is the NullPointerException (Cannot invoke "listfix.view.GUIScreen.getMediaLibrary()") resolved?

I do not have a clue what this log-entry refers to. I did not notice anything untoward, sorry. If it, perhaps, refers to GUI-problems while trying to add to the Media Library, please note that I did not notice any problems with it. What else does "listfix.view.GUIScreen.getMediaLibrary() refer to, so I can take another look at it?

• Does PR (represented by this build) break something new?

Do you have anything specific in mind that I should look out for? Running a few quick checks, did not show up any quirks. To be continued.

Does it resolve Double printed tab pane headings of the playlist editors #55 ?

This is the very first test I ran. Unfortunately, this ghost is still hanging around.

•
rollingfile.log
•

[touwys]

Build: listFix_2.5.1-PR89-26

Also see #91

[Borewit]

I do not have a clue what this log-entry refers to

That was the exception you reported #64 (comment)
But in the log file you provided I no longer see it, so that is good.
To bad it was not the cause of #55 as your ghost is still hanging around.

Do you have anything specific in mind that I should look out for?

Nope, just if you noticed I introduced a new problem

[touwys]

That was the exception you reported #64 (comment)

Thank you, I was aware of that, but my words keep on failing me: What I meant is that I do not have a clue what a "NullPointerException" intends — in general, or, as in this issue, in particular. 🤔

Thank you for showing so much patience trying to interpret, and explaining what I am posting here. Understandably, it is important that we stay on the same page. However, it appears that I am not even on the same chapter yet. 🤣

[Borewit]

What I meant is that I do not have a clue what a "NullPointerException" intends

When programming we use variables. Just like variables in mathematical formula's. A special variable is reference to a certain type of Object. An Object is collection of functions, variables (including references to other objects).

A reference to an object may be null. Which means, it's empty.

Car myCar = new Car(); // We create new object "Car" and store it the instance in reference variable myCar
myCar.drive(); // Now we call the function of the Car instance "myCar": drive()

A NullPointer exception is thrown in the following condition:

Car myCar = null; 
myCar.drive(); // NullPointerException will be thrown here 

We can a function (method) of object instance, which is null.

Same when I want to take my Porsche for a drive, I know how it looks like, but I don't own one (it is null), so unfortunately I cannot drive it.

Ref:

• https://www.geeksforgeeks.org/null-pointer-exception-in-java/

[touwys]

Thank you.

[Borewit]

Fixed in release v2.6.0