(Trying to) take notes from the lock screen

All the way back in early 2024, Android Authority wrote that in a future update Google Keep might let you jot notes from the lock screen of an Android tablet. The Android 14, Android 14-QPR1, and Android 14-QPR2 release notes mention that the

NOTES role in Android 14 supports the note-taking feature and increases productivity of Android tablets. With the NOTES role, OEMs can give the end users a consistent note-taking experience when using a stylus on an Android tablet on the users' preferred note-taking app. For more details, see NOTES on Android Roles.

While that sounds great, why should this feature be limited to tablets? I believe being able to quickly and easily jot down notes on the go would significantly boost productivity. My Surface Duo supports stylus input. And with the DUO-DE custom ROM, it runs Android 15, so it should be well prepared for a quick test drive, right?

Well. Without any preparations the Default apps settings page looked like this:

Nothing related to note taking. However, in Developer options, we can force enable the Notes role.

Once I activated Force enable Notes role and restarted the device a few times, a new entry appeared in Default apps. And, even better, Keep Notes was not only listed but could even be selected as the default notes app:

The final step is to add a shortcut to the lock screen.

While it looked like I had set everything up correctly, the lock screen just did not show a Note taking icon. Changing postures had no effect. Neither did tapping on the screen with a stylus help. Being a developer, I was curious to learn what might be going on. But how do we debug system features, particularly if we are not too deep into AOSP internals?

Keyguard Quick Affordances

The first question that occurred to me was How do these lock screen icons work? Buried deep inside android.googlesource.com, there is a very interesting document titled Keyguard Quick Affordances.

To implement a new Quick Affordance, a developer may add a new implementation of KeyguardQuickAffordanceConfig in the packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance package/directory and add it to the set defined in KeyguardDataQuickAffordanceModule.

So, we should find a reference to note taking in packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance, right? Let's take a look.

While the main branch currently does not contain code related note taking, it apparently did on Jan 19, 2023, until it was merged into tm-qpr-dev.

Now, considering these files, can we find out why we can add the Note taking icon but not use the feature in the end?

As far as I understand it, NoteTaskModule decides inside provideIsNoteTaskEnabled() whether to enable note taking or not. Now, given my setup, roleManager.isRoleAvailable(NoteTaskIntentResolver.NOTE_ROLE) should evaluate to true. What about featureFlags.isEnabled(Flags.NOTE_TASKS)? Doing an Android Code Search on Flags.NOTE_TASKS shows this piece of code:

Invoking releasedFlag() returns an instance of ReleasedFlag, which, according to the documentation, is true by default. If the value is not changed to false at some point, both conditions inside provideIsNoteTaskEnabled() are met. And this kind of makes sense, because kindly recall that I could add the note taking icon in the lock screen settings. It just won't be visible on the lock screen.

Let me mention one more class, NoteTaskIntentResolver. It is

responsible to query all apps and find one that can handle the ACTION_CREATE_NOTE

How about taking its code and adding it to an ordinary app? This should simplify debugging. If Google Keep supports the Notes role, it should be returned here, right? Well, let's see.

Here are two slightly adapted versions of resolveIntent() and resolveActivityNameForNotesAction().

fun resolveIntent(): Intent? {
  val intent = Intent(ACTION_CREATE_NOTE)
  val resolveInfoFlags = ResolveInfoFlags.of(
      PackageManager.MATCH_DEFAULT_ONLY.toLong()
  )
  for (info in packageManager.queryIntentActivities(
      intent, resolveInfoFlags
  )) {
      val packageName = 
        info.activityInfo.applicationInfo.packageName
        ?: continue
      val activityName =
        resolveActivityNameForNotesAction(packageName)
        ?: continue
      return Intent(ACTION_CREATE_NOTE)
        .setPackage(packageName)
        .setComponent(ComponentName(packageName, activityName))
        .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
  }
  return null
}

private fun resolveActivityNameForNotesAction(
  packageName: String
): String? {
  val intent = Intent(ACTION_CREATE_NOTE).setPackage(packageName)
  val resolveInfoFlags = ResolveInfoFlags.of(
        PackageManager.MATCH_DEFAULT_ONLY.toLong()
  )
  packageManager.resolveActivity(
    intent,
    resolveInfoFlags
  )?.activityInfo?.let { activityInfo ->
    if (activityInfo.name.isNullOrBlank()) return null
    if (!activityInfo.exported) return null
    // FLAG_SHOW_WHEN_LOCKED marked as hidden
    if (activityInfo.flags and 0x800000 == 0) return null
    // FLAG_TURN_SCREEN_ON marked as hidden
    if (activityInfo.flags and 0x1000000 == 0) return null
    return activityInfo.name
  }
  return null
}

If you want to write a note taking app that can be summoned from the lock screen, resolveActivityNameForNotesAction() nicely tells you how your activity should be configured.

Wrap up

At this point, I hope you are eager to learn if Keep Notes showed up here.

It. Did. Not.

That came as a surprise. Afterwards I checked Standard apps and found out that Keep notes no longer appears to be a candidate for the Notes role. While I don't want to speculate, a reasonable explanation might be that an update (in fact, I received one after I took the screenshots you saw above) deactivated the feature for some devices or device categories. Which would be really sad. As I mentioned at the beginning, limiting the ability to start note taking apps from the lock screen to tablets (or vendors that choose to support it) feels pretty short-sighted. And, no, I don't want to say Hey Gemini, please open the Notes app. I just want a quick way to open that app. Period. For now I consider this a prime example of a lost opportunity.

So, at least on my Surface Duo I can't take notes from the lock screen. Did you have some luck on your device? Please share your thoughts in the comments.