Datatable column order state is not saved

[juanparati]

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I observed that datatable code has missing the part save the column order state.

For example the method "onColumnHeaderDrop" doesn't call the "saveState" method, exactly like it happens with the methods "onColumnResizeEnd" or "updated".

The cause may also that state is not saved because datatable 2.9.1 calls to "beforeUnmount" instead of "beforeDestroy" method. The "beforeUnmount" is not available in Vue 2.x.

Expected behavior
The order of the columns should be saved and restored when the cache the state is used in a datatable exactly like it happens with the filters, sorting and data.

Minimal reproduction of the problem with instructions

1. Set a datatable with "state-key" and "state-storage" and "reorderable-columns".
2. Drag and drop one of the table column to another position.
3. Reload databable page.

• Vue version: 2.6.11

• PrimeVue version: 2.9.1

• Browser: all

[juanparati]

I found the solution to this problem:

It seems that state is saved correctly, the problem is when the state is restored.

I replaced:

 if (this.reorderableColumns) {
                this.d_columnOrder = restoredState.columnOrder;
 }

by

 if (this.reorderableColumns) {
                this.$nextTick(() => this.d_columnOrder = restoredState.columnOrder);
 }

and now it works!.

I also recomend to rename "beforeUnmount" method to "beforeDestroy" on Vue 2.x component and save the state on "beforeDestroy" instead of "update". The component peformance improve a bit with this change.

[mertsincan]

Fixed in 6c97e0a