Reordering can be enabled by setting allowReordering property as true. Reordering can be done by drag and drop the column header from one index to another index within the TreeGrid. The location in which the column to be placed, will be indicated by two arrows symbols. In this demo, you can reorder columns by drag and drop Injecting Module: TreeGrid component features are segregated into individual feature-wise modules. To use reordering feature, we need to inject ReorderService into the @NgModule.providers section. More information on the TreeGrid instantiation can be found in this documentation section.