GUI
Bitcoin-S Graphical User Interface
There is now a GUI built using scalafx to allow users who do not wish to use the command line interface to interact with a Bitcoin-S wallet. This GUI is currently very minimal and looks something like this:
At the time of writing this document, creating addresses and sending Bitcoin are the only supported wallet functionalities in the wallet's RPC API. The expansion of this interface will enable a more robust GUI and this issue is being tracked here.
Running the GUI
It is required to use java11 to run the GUI
There are two ways to run the GUI
Bundled version (easy)
This command will start both the bitcoin-s server and the GUI at the same time
sbt bundle/run
Standalone version (advanced)
The GUI will only function properly if it can connect to the bitcoin-s server which must be running in the background before running the GUI.
To run the gui, simply execute
sbt gui/run
The gui can be built into an executable using the sbt native packager.
ScalaFX
ScalaFX is a scala library wrapping JavaFX which is itself a java interface to GTK (which is useful to know when googling for answers as it is easier to search for answers in GTK or sometimes javafx and then translate them to scalafx).
ScalaFX itself requires the dependency
"org.scalafx" %% "scalafx"
but full use of the library requires also adding these dependencies:
"org.openjfx" % "javafx-base"
"org.openjfx" % "javafx-controls"
"org.openjfx" % "javafx-fxml"
"org.openjfx" % "javafx-graphics"
"org.openjfx" % "javafx-media"
"org.openjfx" % "javafx-swing"
"org.openjfx" % "javafx-web"
which for some reason must all be classified by the OS of the machine they are running on.
A GUI can now be built by creating an object which extends scalafx.application.JFXApp and setting the stage var to a new JFXApp.PrimaryStage whose scene is your Node (where Node is the super-class in this framework for all GUI elements).
ScalaFX Examples
Aside from looking at how the Bitcoin-S GUI is implemented, for more useful examples of ScalaFX, see these tutorials and specifically this one which I think is most illustrative.