ExtJs4 - What is the equivalent to the grid ColumnModel?

Question

What is the equivalent to the ExtJs3 Ext.grid.ColumnModel in ExtJs4?

What I want to do is hide a column, I did something like below in ExtJs3:

Answer 1

You can hide/show column using setVisible method of Ext.grid.column.Column:

grid.columns[1].setVisible(false);