perf(android): avoid screen and device-type IPC candidates

.changeset/calm-clocks-rest.md

@@ -0,0 +1,5 @@
+---
+"posthog-android": patch
+---
+
+Avoid main-thread IPC candidates in screen autocapture and device type detection. Screen autocapture now uses the activity's current title, which may produce a different `$screen_name` for `$screen` events when apps set titles dynamically.

posthog-android/src/main/java/com/posthog/android/internal/DeviceUtils.kt

@@ -1,6 +1,5 @@
 package com.posthog.android.internal
 
-import android.app.UiModeManager
 import android.content.Context
 import android.content.res.Configuration
 import android.os.Build
@@ -70,11 +69,9 @@ internal fun getDeviceType(context: Context): String? {
         return "TV"
     }
 
-    val uiManager = context.getSystemService(Context.UI_MODE_SERVICE) as UiModeManager?
-    uiManager?.let {
-        if (it.currentModeType == Configuration.UI_MODE_TYPE_TELEVISION) {
-            return "TV"
-        }
+    val uiModeType = context.resources.configuration.uiMode and Configuration.UI_MODE_TYPE_MASK
+    if (uiModeType == Configuration.UI_MODE_TYPE_TELEVISION) {
+        return "TV"
     }
 
     val deviceTypeFromResourceConfiguration = getDeviceTypeFromResourceConfiguration(context)

posthog-android/src/main/java/com/posthog/android/internal/PostHogAndroidContext.kt

@@ -96,6 +96,8 @@ internal class PostHogAndroidContext(
         }
 
         context.telephonyManager()?.let {
+            // TelephonyCallback requires location permission to expose the operator name. Keep this
+            // property read, which primarily uses telephony system properties and cached mapping.
             val networkOperatorName = it.networkOperatorName
             if (!networkOperatorName.isNullOrEmpty()) {
                 dynamicContext["\$network_carrier"] = networkOperatorName

posthog-android/src/main/java/com/posthog/android/internal/PostHogAndroidDateProvider.kt

@@ -10,10 +10,11 @@ import java.util.Date
 /**
  * Provides the current time, corrected to network time when available.
  *
- * [Clock.millis] on the clock returned by [SystemClock.currentNetworkTimeClock] performs a Binder
- * IPC to a system service on every call, so querying it on each timestamp (e.g. on every touch
- * event) blocks the calling thread and can ANR under load. Instead the network time is sampled at
- * most once per [refreshIntervalMs] and subsequent timestamps are derived from the monotonic
+ * [Clock.millis] on the clock returned by [SystemClock.currentNetworkTimeClock] reads an OS-cached
+ * network-time sample; it does not make an NTP or other network request. Retrieving that cached
+ * sample uses Binder on Android 13-15, while Android 16 can use shared memory with a Binder fallback.
+ * We intentionally accept at most one synchronous IPC per [refreshIntervalMs] to keep this cache
+ * simple. Subsequent timestamps are derived from the monotonic
  * [android.os.SystemClock.elapsedRealtime] delta since that anchor.
  *
  * Once a sample has succeeded, later sampling failures extend the existing anchor rather than

posthog-android/src/main/java/com/posthog/android/internal/PostHogAndroidUtils.kt

@@ -133,21 +133,20 @@ internal fun Context.telephonyManager(): TelephonyManager? {
     return getSystemService(Context.TELEPHONY_SERVICE) as? TelephonyManager
 }
 
-@Suppress("DEPRECATION")
 internal fun Activity.activityLabelOrName(config: PostHogAndroidConfig): String? {
     return try {
-        val activityInfo = packageManager.getActivityInfo(componentName, GET_META_DATA)
-        val activityLabel = activityInfo.loadLabel(packageManager).toString()
+        val activityLabel = title?.toString().orEmpty()
+        val activityName = componentName.className
         val applicationLabel = applicationInfo.loadLabel(packageManager).toString()
 
         if (activityLabel.isNotEmpty() && activityLabel != applicationLabel) {
-            if (activityLabel == activityInfo.name) {
+            if (activityLabel == activityName) {
                 activityLabel.substringAfterLast('.')
             } else {
                 activityLabel
             }
         } else {
-            activityInfo.name.substringAfterLast('.')
+            localClassName.substringAfterLast('.')
         }
     } catch (e: Throwable) {
         config.logger.log("Error getting the Activity's label or name: $e.")

posthog-android/src/test/java/com/posthog/android/Utils.kt

@@ -8,7 +8,6 @@ import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
 import android.content.SharedPreferences
-import android.content.pm.ActivityInfo
 import android.content.pm.ApplicationInfo
 import android.content.pm.PackageInfo
 import android.content.pm.PackageManager
@@ -53,30 +52,19 @@ public fun mockScreenTitle(
 ): Activity {
     val activity = mock<Activity>()
     val pm = mock<PackageManager>()
-    val ac =
-        mock<ActivityInfo>().apply {
-            name = activityName
-        }
     val appInfo = mock<ApplicationInfo>()
 
-    whenever(ac.loadLabel(any())).thenReturn(title)
-    whenever(appInfo.loadLabel(any())).thenReturn(applicationLabel)
-
     if (throws) {
-        whenever(
-            pm.getActivityInfo(
-                any(),
-                any<Int>(),
-            ),
-        ).thenThrow(PackageManager.NameNotFoundException())
+        whenever(activity.title).thenThrow(IllegalStateException("title unavailable"))
     } else {
-        whenever(pm.getActivityInfo(any(), any<Int>())).thenReturn(ac)
+        whenever(activity.title).thenReturn(title)
     }
-
-    whenever(pm.getApplicationInfo(any(), any<Int>())).thenReturn(appInfo)
+    whenever(appInfo.loadLabel(any())).thenReturn(applicationLabel)
 
     val component = mock<ComponentName>()
+    whenever(component.className).thenReturn(activityName)
     whenever(activity.componentName).thenReturn(component)
+    whenever(activity.localClassName).thenReturn(activityName)
     whenever(activity.packageManager).thenReturn(pm)
     whenever(activity.applicationInfo).thenReturn(appInfo) // Ensure applicationInfo is not null
 

posthog-android/src/test/java/com/posthog/android/internal/DeviceUtilsTest.kt

@@ -0,0 +1,60 @@
+package com.posthog.android.internal
+
+import android.content.Context
+import android.content.pm.PackageManager
+import android.content.res.Configuration
+import android.content.res.Resources
+import android.util.DisplayMetrics
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.runner.RunWith
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.never
+import org.mockito.kotlin.verify
+import org.mockito.kotlin.whenever
+import org.robolectric.annotation.Config
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+@RunWith(AndroidJUnit4::class)
+@Config(sdk = [28])
+internal class DeviceUtilsTest {
+    private fun contextWithConfiguration(configuration: Configuration): Context {
+        val context = mock<Context>()
+        val resources = mock<Resources>()
+        val packageManager = mock<PackageManager>()
+        whenever(context.resources).thenReturn(resources)
+        whenever(context.packageManager).thenReturn(packageManager)
+        whenever(resources.configuration).thenReturn(configuration)
+        whenever(resources.displayMetrics).thenReturn(DisplayMetrics())
+        whenever(packageManager.hasSystemFeature("amazon.hardware.fire_tv")).thenReturn(false)
+        return context
+    }
+
+    @Test
+    fun `returns TV from the local resource configuration`() {
+        val configuration = Configuration()
+        configuration.uiMode = Configuration.UI_MODE_TYPE_TELEVISION or Configuration.UI_MODE_NIGHT_YES
+        val context = contextWithConfiguration(configuration)
+
+        assertEquals("TV", getDeviceType(context))
+        verify(context, never()).getSystemService(Context.UI_MODE_SERVICE)
+    }
+
+    @Test
+    fun `keeps tablet classification for non television UI mode`() {
+        val configuration = Configuration()
+        configuration.uiMode = Configuration.UI_MODE_TYPE_NORMAL
+        configuration.smallestScreenWidthDp = 600
+
+        assertEquals("Tablet", getDeviceType(contextWithConfiguration(configuration)))
+    }
+
+    @Test
+    fun `keeps mobile classification for non television UI mode`() {
+        val configuration = Configuration()
+        configuration.uiMode = Configuration.UI_MODE_TYPE_NORMAL
+        configuration.smallestScreenWidthDp = 599
+
+        assertEquals("Mobile", getDeviceType(contextWithConfiguration(configuration)))
+    }
+}

posthog-android/src/test/java/com/posthog/android/internal/PostHogActivityLifecycleCallbackIntegrationTest.kt

@@ -12,6 +12,7 @@ import com.posthog.android.mockScreenTitle
 import org.junit.runner.RunWith
 import org.mockito.kotlin.any
 import org.mockito.kotlin.mock
+import org.mockito.kotlin.never
 import org.mockito.kotlin.verify
 import kotlin.test.BeforeTest
 import kotlin.test.Test
@@ -183,7 +184,32 @@ internal class PostHogActivityLifecycleCallbackIntegrationTest {
     }
 
     @Test
-    fun `onActivityStarted returns activityInfo name if labels are the same`() {
+    fun `onActivityStarted does not query activity info`() {
+        val sut = getSut()
+        val activity = mockScreenTitle(false, "Title", "com.example.MyActivity", "AppLabel")
+        val fake = createPostHogFake()
+
+        sut.install(fake)
+        sut.onActivityStarted(activity)
+        sut.uninstall()
+
+        verify(activity.packageManager, never()).getActivityInfo(any(), any<Int>())
+        assertEquals("Title", fake.screenTitle)
+    }
+
+    @Test
+    fun `onActivityStarted returns activity name when the label is the class name`() {
+        val fake =
+            executeCaptureScreenViewsTest(
+                title = "com.example.MyActivity",
+                activityName = "com.example.MyActivity",
+            )
+
+        assertEquals("MyActivity", fake.screenTitle)
+    }
+
+    @Test
+    fun `onActivityStarted returns activity name if labels are the same`() {
         val fake =
             executeCaptureScreenViewsTest(
                 captureScreenViews = true,