Align Objects > Centered, Frame Horizontal (Modify Menu)

This command can be used to center all kinds of objects horizontally relative to a rectangular frame. They are moved horizontally so that they are the same distance from the left and right edges of the frame. All chosen objects are treated as a single item, i.e. they are all moved by the same amount.

All the objects to be centered have to be chosen. Click on objects to choose them.

The first corner point of the frame can be entered by clicking the mouse anywhere in the drawing.

The second corner point of the frame can be entered by clicking the mouse anywhere in the drawing.