For the purpose of the tutorial, we will assume you already have an existing Android application in which you have a feed or list of items. As the Flipper team, we obviously concern ourselves mostly with sea mammals, so this is what our app displays. The actual display logic is not what's interesting here, but how we can make this data available in our Flipper desktop app.
Part of what makes Flipper so useful is allowing users to inspect the internals of their app. In this case, we'd like to see the specific sea mammal data the app is handling, so let's write a plugin to make that easy.
You can find the source code of the project on GitHub.
Creating a Plugin
On Android, a Flipper plugin is a class that implements the
The interface is rather small and only comprises four methods:
package.jsonwe will look into later in this tutorial.
onConnect(FlipperConnection): This method is called when the desktop app connects to the mobile client and is ready to receive or send data.
onDisconnect(): We're sure you can figure this one out.
runInBackground() -> Boolean: Unless this is true, only the currently selected plugin in the Flipper UI can communicate with the device.
Let's implement these methods for our sealife app:
The two interesting bits here are
newRow sends a message
to the desktop app and is identified with the same name "newRow".
For our sample app, we're dealing with a static data source. However, in real
life, you will likely dynamically receive new data as the user interacts with
the app. So while we just send all the data we have at once in
you would normally set up a listener here to instead call
newRow as new data
You may have noticed that we don't just send random
Objects over the wire but
FlipperObjects instead. What are they? A
FlipperObject works similar
to a JSON dictionary and has a limited set of supported types like strings,
integers and arrays. Before sending an object from your native app to the
desktop, you first need to break it down into
Registering your Plugin
Now all you need to do is let Flipper know about your new plugin. You do this
addPlugin on your
FlipperClient, which is normally created
at application startup.