A control that supports its own in-place editing. See EditableText for an example.

The user interface for the read and edit states can be customized by setting the readClass() and editClass() properties, respectively. The edit control is only instantiated on demand, when the Editable's editing() property is set to true for the first time. This allows an Editable control to avoid loading extra user interface elements until they're actually needed.

Editable gets its mode-switching behavior by deriving from Modes.