Kendo Grid.dataItem loop not working

Question

So my aim it to loop through all selected item in my kendo grid, but after the first iteration the dataItem method returns undefined.

function myFunction() {
var selectedItem = $("#DropDown").val();
var grid = $("#Grid").getKendoGrid();
var selectedItems = grid.select();
for (var i = 0; i < selectedItems.length; i++) {
    var dataItem = grid.dataItem(selectedItems[i]);
    if (dataItem != undefined)
        dataItem.set("Item", SelectedItem);
}
}

Does anyone know why this might be happening?

score 1 · Accepted Answer · answered Jul 25 '18 at 17:57

That happens because set() performs a grid refresh behind-the-scenes so the DOM is recreated. The array you had with the selected items is lost. You can't rely on the tr's references. As a suggestion I think you can use they indexes instead:

function myFunction() {
    var selectedItem = $("#DropDown").val();
    var grid = $("#Grid").getKendoGrid();
    var selectedItems = grid.select().toArray().map((item) => { return $(item).index(); });

    for (var i = 0; i < selectedItems.length; i++) {
        var currentItem = grid.tbody.find(`tr:eq(${selectedItems[i]})`);
        var dataItem = grid.dataItem(currentItem );
        if (dataItem != undefined)
            dataItem.set("Item", SelectedItem);
    }
}

var selectedItems = grid.select().toArray().map((item) => { return $(item).index(); });

This line gets an array of indexes from the selected grid rows to iterate further ahead;
var currentItem = grid.tbody.find(`tr:eq(${selectedItems[i]})`);

This line retrieves the selected row from by the index.

Demo

Your solution did work and was valid, however I used your explanation to solve it slightly differently. I created an array called dataItems and pushed each dataItem in it, then looped through that. I know this involves using more lines but I think its easier to see whats going on. — GeorgeB, Jul 26 '18 at 07:43
@GeorgeB indeed can be even better than what I proposed! Well done! — DontVoteMeDown, Jul 26 '18 at 13:06

Kendo Grid.dataItem loop not working

1 Answers1