Local Storage or Cloud

Regardless of your operating system or device, Listing 11 will store the data for you. However, many apps now want to have centrally stored information on a cloud service. The great news is that Fyne supports this too! Using exactly the same code from Listing 11, you can have a cloud back end for your data, which is set up by simply calling SetCloudProvider for your app with a suitable provider description. You can find more information about setting this up in a recent FyneConf video [3].

Packaging and Installing

Once you have a completed your app, the next step is make it more readily available either for yourself or others.

First, you need to add an icon before installing or sharing the app. Although Fyne is a vector graphics-based toolkit, you will need a bitmap image for the app icon. For greatest compatibility, create a 1024x1024 PNG file, name it Icon.png, and save it to the project folder. Once created, this will be used as the app icon. The best way to bundle apps is to use the fyne command-line tool:

> go install fyne.io/fyne/v2/cmd/fyne@latest

Once installed you can call fyne package to set up an app bundle. It will use the appropriate format for the current operating system. You can also install it at the same time using fyne install. This will package the app and put it into your standard app location (/usr/local/bin for most Linux distributions).

If you get a "command not found" message, be sure to check that the Go binary location (usually ~/go/bin) is in your $PATH. Once complete, the app will be available in your favorite app launcher (Figure 4).

Figure 4: You can launch the to-do app from your favorite launcher.

Sharing with Others

Before sharing your app, you should consider adding a tutorial for new users. This is really easy for a to-do list app because you can just add items to the UI when the app has not been used before by simply replacing the call to Properties.String with Properties.StringWithFallback. The fallback case will be used when the requested preference key has not previously been saved. Try the following:

p.StringWithFallback("items",
  "Do this item"+joiner+"Learn Fyne!"
  +joiner+"Build an app")

Now, you can package the code for distribution. The command fyne package will prepare a bundle (for a Linux host, this will create todoapp.tar.xz). The bundle will contain your binary, an icon file, and the metadata needed to install on other computers. These binaries are relocatable, so it will work for computers with a different configuration. New app users will see the welcome screen shown in Figure 5 with a tutorial and an icon!

Figure 5: The welcome screen now contains a tutorial and an app icon.