This commit changes the Magikeyboard service behavior so that KeePassDX
is able to run in Samsung DeX mode. Currently, the app cannot run in
DeX mode because apps which have services using `BIND_INPUT_METHOD` are
blocked.
A new broadcast receiver has been added to listen for DeX's enter/leave
events [1] and disable/enable the `Magikeyboard` service appropriately.
The enabled state of a service lives in the Android framework's
`PackageManager` and survives app crashes and device reboots (though it
does get reset when app data is cleared).
Additionally, an extra check is added to `FileDatabaseSelectActivity` to
ensure the service's enabled state is correct. This is necessary if the
app crashes or is force quit within DeX mode and then the user exits DeX
mode. Otherwise, the service would stay disabled until the user entered
and exited DeX again.
With the new behavior, KeePassDX will generally just work with DeX,
though there's one caveat: after the initial installation, the user must
open the app once outside of DeX. Otherwise, Android will not trigger
the broadcast receiver. This could be fixed by making the service
intially disabled in the manifest with `android:enabled="false"`, but
Android's Settings app in SDK 15 through 25 does not correctly refresh
the keyboard list when changing the service from disabled to enabled.
I opted *not* to introduce different behavior based on the API version.
[1] https://developer.samsung.com/sdp/blog/en-us/2017/07/27/samsung-dex-how-to-detect-the-samsung-dex-modeFixes: #245
Signed-off-by: Andrew Gunnerson <chillermillerlong@hotmail.com>
