The Anti-aliasing button on the Status Bar is a toggle to enable or disable the behavior. When depressed, Anti-aliasing is switched on such that the specified sampling level is automatically applied at the end of every change in view. If Anti-aliasing is active (button is depressed), Anti-aliasing is applied to all Render views when Render mode is not shown (for use in Imageports with Reports), before exporting as a JPG, PNG or BMP and before printing the image.
From the Status Bar
depress the button to enable automatic anti-aliasing: 
. Select the desired sampling level.