The columns configuration of the Grid should be an array of objects with settings for each column.
The provided example assigns the data object as column configuration, which will not work, first because the data object is not an array, and second, because it does not contain any meaningful column settings that the Grid can parse and use. In other words, the column settings are currently being ignored and the Grid autogenerates its columns.
To render data with nested objects with the Kendo UI Grid, you need to break the data into fields for each column.
You could either set the street and city as separate columns, in which case you can do it as demonstrated here:
Or alternatively you could use a column template and group the street and city into one column like in this dojo demonstration:
A similar example with nested objects is also available at:
You can find more information about column templates here:
I hope this answers your question.
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