dataView.onRowsChanged event doesn't always fire when the rows have changed

When filtering rows, the dataView’s onRowsChanged event does not always get called when the rows have changed. This happens when filtering down the list such that the new rows are the first X rows from the current rows.

For example: Your data consists of three records in this order: “Task 01”, “Task 02”, “Task 03” When filtering on rows with a “0”, the onRowsChanged event correctly does not fire because all 3 rows are still there. If I then filter to “01”, the onRowsChanged event still does not fire even though only 1 row is now showing. Had I filtered on “02”, the onRowsChanged event would have fired.

The issue lies in how the dataView checks for row changes in its getRowDiffs function. At a basic level, this function loops through the newly filtered rows and compares them to the rows before the new filter. As long as the new rows exist in the the original rows in the same order, the function does not report any diffs. It is ignoring that the original row list contains more rows than the new list. All of these additional rows should be considered diffs.

The getRowDiffs function affects the onRowsChanged event because dataView.refresh() calls recalc() which ultimately returns an array of row indexes that changed via the getRowDiffs function. The refresh function will only fire the onRowsChanged event if getRowDiffs() reports any diffs.

Here is a JSFiddle illustrating this issue: https://jsfiddle.net/bcnap2dm/ I used the code from this example as a starting point: http://6pac.github.io/SlickGrid/examples/example4-model.html From there, all I did was simplify the data set and add toastr notifications to show when the onRowsChanged event is triggered.

[6pac]

Look, my apologies for this. My thoughts are that I should update my Wiki quite broadly (it hasn’t changed since MLeibman). It’s been on the TODO list for some time. I’ve just been too busy. Will try to get something up in the next month. Anyone is welcome to document it and make a pull request to the Wiki … 😃

[6pac]

https://github.com/6pac/SlickGrid/issues/344