The Android back button provides a working back function, and the Swap
"close" button on the upper left already provides a reset function. So this
turns the "back" button to be a "try again" button which re-runs the
connection process.
The Receiver superclass is not reusing difficult code, but it is hiding the
simple list of UI configuration that it does.
This also eliminates the "error" TextView and just reuses the existing
TextView for error messages.
Almost all of the nearby/swap view classes could be condensed into a single
base class that is instantiated in the view XML. This is the first step
towards making that happen.
It also lays the groundwork where "steps" are all SwapViews. The
original concept of "steps" put all steps together, whether
F-Droid could control them or not. For example, the Views were
mixed with the system Bluetooth prompts. This is the first step
towards converting the steps to always be SwapViews, which are
always under control of this app.
When coming back to a SwapView/step, it does not seem feasible to handle
automatically restarting things like permissions and Bluetooth prompts. If
there is a way, it should be possible to first load the proper SwapView
instance, then trigger the system prompt. The makes the SwapView a pure
View, without any Controller in it.
