most android apps that need any kind of auth go straight to biometrics or firebase. fine — but what if you just need a simple PIN lockscreen? no backend, no cloud calls, just "enter your code to continue".
that's what AndroidAppLockscreen does.
i built it after copy-pasting the same lockscreen implementation across three different projects. the design is inspired by Diary — clean, minimal, nothing fancy.
what it handles
- set password
- check password on launch
- change password
- disable password
- forgot password flow
- customisable background color
setup
add the JitPack repo and one dependency:
implementation 'com.github.p32929:AndroidAppLockscreen:1.2'
extend your activities with LockscreenHandler, then in MainActivity's onCreate:
EasyLock.checkPassword(this);
first launch, no password set → does nothing. password set → blocks app until correct code is entered.
managing passwords after that:
EasyLock.setPassword(activity);
EasyLock.changePassword(activity);
EasyLock.disablePassword(activity);
the non-obvious part
the tricky bit wasn't the UI. it was activity lifecycle. you don't want the lockscreen triggering on screen rotation or when the user returns from a camera/file picker intent. LockscreenHandler handles all of that — it knows the difference between "user left the app" and "activity was recreated internally".
64 stars, 21 forks, MIT licensed.
repo: https://github.com/p32929/AndroidAppLockscreen
would love feedback, PRs, or stars if it saves you time. open to building with sharp teams and solo founders — dms open.