The new layout library implements a lot more of the Android graphics stack, so layouts and custom layouts should usually look identical to what you see on a running Android device. However, there are some graphics operations that are not fully implemented in the tool. In order to make it clear that what you see is not what you get, the layout library provides a "rendering fidelity" warning which tells you which graphics operation was not supported and warning you that the layout may not look correct.
Here is an example of what you see if you run the Android Accessory Development Kit's demo project:
There is not much you can do about this warning, other than to be informed that you may need to verify the graphics on a running device. However, having the error there persistently can be annoying since it takes up valuable screen real estate.
As you can see in the above screenshot, we now give you a way to turn off this warning via the hyperlink. When you click the hyperlink the layout is rendered again and the warning is suppressed:
Note that the error is only suppressed for the current running IDE session, so you'll need to click it again next time you open the same project. The reason for this is that the error is suppressed globally, not for a particular project or a specific layout, so we don't want you to suppress the error once and forget that you did, and then much later open some unrelated project and wonder why it doesn't look right. In the future we might try to make the error more closely associated with a specific layout in a specific project such that it can be suppressed for a longer duration.
In the meantime this will hopefully work with advanced graphics custom views more convenient.