First of all, thank you for providing the state management feature. For me it's one of the most important features of a grid component.
But unfortunately it fails to restore the columns state. This is because each time a grid component and it's columns are instantiated, new IDs are created for the columns. When loading state the columns are identified by their IDs.
When a column is persisted with e.g. id 'k-grid-column-1' and the grid will be destroyed and re-created, then the new column ID is not identical with the old one. Thus restoring the column's state will fail.
Please have a look to this StackBlitz example: https://stackblitz.com/edit/angular-vauqyshn?file=src%2Fapp%2Fapp.component.ts
A possible workaround is to save also the column's field property and later use it to re-map the saved id to the new id.
A better solution may be to extend the GridColumnComponent with something like a "PersistenceKey" property, which will be used for identifying a column. A directive may also work. Otherwise generating non transient unique ids for the grid columns will also work.
Best regards,
Holger
Additional information:
This is how the IDs are genrated
The columnId variable is shared with all grid instances during the whole lifetime of the application.
Hello Martin,
I have updated the example to demonstrate the problem more precisely.
https://stackblitz.com/edit/angular-vauqyshn?file=src%2Fapp%2Fapp.component.ts
Here are the steps to reproduce the problem:
#1 Log grid columns
#2 Hide a grid column and log grid columns
#3 Save state
#4 Hide and show the grid
#5 Log grid columns
New IDs are generated. Originally IDs were [0, 1], new IDs are [2, 3]
#6 Load state
#7 Columns (hidden column) are not restored
Look at this excerpt from from the GridComponent's source code. When loading state, columns are identified by their IDs.
I hope this clarifies the problem.
Regards,
Holger