In-app updates

How PEK TV finds and installs a new release, and how to publish one.

View source on GitHub

PEK TV checks GitHub for a newer release every time it starts. If there is one, an "A new version is available" screen comes up before the app. Update now downloads the apk and hands it to Android to install. Not now opens the app; nothing is remembered, so the screen is back at the next start until the app is updated.

Publishing a release (what the app looks for) #

1. In android/app/build.gradle raise pekBaseCode by 1 (18 -> 19). Android refuses an install whose versionCode is not higher.
2. Push a tag: git tag v2.2.0 && git push origin v2.2.0.
3. build_android.yml builds a signed release and publishes a GitHub release with PEK-TV-<version>-release-arm64-v8a.apk and PEK-TV-<version>-release-armeabi-v7a.apk. The tag (without the v) becomes the app's versionName and is what installed apps compare against.

Rules the app follows:

• It reads the release list, so pre-releases count. The newest tag with a matching apk wins.
• The CPU type is taken from the installed versionCode (ends in 1 = 32-bit, 2 = 64-bit), so a 64-bit install stays 64-bit.
• Debug builds, -dev.N builds and local builds never show the screen.
• The apk is checked against GitHub's sha256 for the asset when GitHub provides one. Android additionally refuses any apk signed with a different key than the installed app, so release builds must always use the same keystore.
• Needs a public repository (R3CT01/PEK-TV, set in flutter_ui/lib/src/app_update.dart).

What Android allows #

Android never lets a normal app update itself with no prompt at all. The person turns on "Install unknown apps" for PEK TV once (the screen sends them there), and Android shows its own confirmation. On Android 12+ Android may skip that confirmation for updates of an app it already installed this way.

"What's new" screen (after an update) #

After the app was updated, the first start shows a What's new in PEK TV x.y.z screen once, then the app. It is separate from the "A new version is available" screen above (that one comes first, before the update is installed).

Every release, before you push the tag:

1. Add a ReleaseNotes('x.y.z', 'Short title', ['line', 'line', ...]) at the TOP of releases in flutter_ui/lib/src/whats_new.dart. x.y.z must be the tag you push, without the v.
2. Raise version: in flutter_ui/pubspec.yaml and pekBaseCode in android/app/build.gradle (see "Publishing a release").

How it behaves:

• The last version the person saw is remembered on the device (not per profile). The notes are shown when the running version has an entry newer than that. Someone who skips versions sees every entry in between, newest first.
• The first time (nothing remembered yet) only the newest entry is shown, not the whole history. A brand-new install sees it too.
• A release with no entry shows nothing.
• -debug / -dev.N builds use the notes of their base version, so you can check the text on a dev build.
• The version is remembered when Continue is pressed, so closing the app on the screen shows it again at the next start.
• On a TV, OK presses Continue and up / down scroll a long list.