Column sort order not properly stored

[Siedlerchr]

There is somehow a bug in storeColumnPreferences

Even when I change the sort oder of one column

From debugging I noticed it's always empty and this is the root issue why the export does not take into account the current table order

jabref/src/main/java/org/jabref/preferences/JabRefPreferences.java

Lines 1932 to 1935 in 2c7715c

	putStringList(COLUMN_SORT_ORDER, columnPreferences
	.getColumnSortOrder().stream()
	.map(MainTableColumnModel::getName)
	.collect(Collectors.toList()));

[Siedlerchr]

Debugged a bit more, it's odd: Sometimes the mainTable.getSortOrder() returns an empty list.
I could reproduce it as follows. Sort by year DESC, e.g. click on the table header for the YEAR column.

jabref/src/main/java/org/jabref/gui/maintable/PersistenceVisualStateTable.java

Lines 36 to 41 in c8f7be8

	private void updateColumnPreferences() {
	preferences.storeColumnPreferences(new ColumnPreferences(
	mainTable.getColumns().stream()
	.map(column -> ((MainTableColumn<?>) column).getModel())
	.collect(Collectors.toList()),
	mainTable.getSortOrder().stream()

@calixtus I remember that you worked on this. Any idea?

[calixtus]

I took a quick look into it. I honestly have no idea why. mainTable.getSortOrder refs directly to the javafx-implementation of a TableView.

[Mehdi-Ayadi]

Hi, i'm a software engineering student and I'm really looking forward to solve this issue if possible. It will be really appreciated to get some guidance or help since i'm new to the project. Thanks!

[Mehdi-Ayadi]

@Siedlerchr i can propose the idea of adding a change listener to the mainTable.getSortOrder that will basically detect whenever there's a change in the sorting order we want ASC or DESC and in a case of DESC order the event will be handled. If it's a good solution i can manage to solve it directly. Thanks in advance !

[Siedlerchr]

Thanks for your interest, but the underlying problem is a bit more complicated and we already have listeners in place if you look closely in the PersistenceVisualStateTable

https://stackoverflow.com/questions/52255126/javafx-tableview-why-does-the-sortorder-listener-does-not-fire-when-i-sort-desc

The question is rather: Why is the getSortOrder list sometimes empty and sometimes not when a listener is triggered?

[calixtus]

Hello @Mehdi-Ayadi nice to hear, that you took interest in JabRef.
To get started, I would suggest you take a look at our developer documentation and start by solving some "good first issues" in our issue tracker to become familiar with the code base of JabRef.
Please note that you have to distinguish in JavaFX between to column sort order and the sort type of a column. Both are stored in JavaFX in separate variables. Right now we are using a changelistener (in PersistentVisualState), but somehow the JavaFX framework does not provide any sort order at all in certain cases. A first step towards a solution would be to debug the ChangeListener and to get an understanding, in which situations it does not work and in which it does.

[Mehdi-Ayadi]

@Siedlerchr @calixtus thank you for your fast replies and for the clarifications ! it's really appreciated. I will take a look a bit more into the details and do my best to come up with a solution.

[Siedlerchr]

Idea for debugging: Split each listener to call a separate method so it's easier to see what listener is when called