The TLayout component is a simple container for FMX visual components. It is rendered as a dashed rectangle at design time, but at runtime, it is completely invisible (transparent).
One of the most straightforward uses of TLayout is to group components together: all components inside the same container share the same positioning system, relative to the upper-left corner of the container. When you move the container, all the contained components move as well. If you change visibility in relation to the container, for example, setting the Visible property to False, the container and all its content will no longer be rendered to the user. Contained objects will retain the ability to have their own visibility that will be combined with that of the parents. This combination also applies to other properties such as Opacity and rotations applied to the components.
For example, if we put a TButton instance inside TLayout and we set the...
