Supports sending window layout info for activities that handle config changes

Fixes bug where activities that handle configuration changes were not
getting the updated window layout info when these would occur

Bug: 186647126
Test: SidecarCompatDeviceTest & Manual testing
Change-Id: I636129f1f5c2bf27909efe787fe88820c30f7509

Author: kford55

window/window/src/androidTest/java/androidx/window/layout/SidecarCompatDeviceTest.kt

@@ -19,9 +19,12 @@
 package androidx.window.layout
 
 import android.content.Context
+import android.content.pm.ActivityInfo
+import androidx.test.core.app.ActivityScenario
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import androidx.test.filters.LargeTest
+import androidx.window.TestConfigChangeHandlingActivity
 import androidx.window.WindowTestBase
 import androidx.window.core.Version
 import androidx.window.layout.ExtensionInterfaceCompat.ExtensionCallbackInterface
@@ -34,6 +37,9 @@ import com.nhaarman.mockitokotlin2.argThat
 import com.nhaarman.mockitokotlin2.atLeastOnce
 import com.nhaarman.mockitokotlin2.mock
 import com.nhaarman.mockitokotlin2.verify
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.TestCoroutineScope
+import kotlinx.coroutines.test.runBlockingTest
 import org.junit.Assert.assertNotNull
 import org.junit.Assume.assumeTrue
 import org.junit.Before
@@ -47,6 +53,7 @@ import org.mockito.ArgumentMatcher
  */
 @LargeTest
 @RunWith(AndroidJUnit4::class)
+@OptIn(ExperimentalCoroutinesApi::class)
 public class SidecarCompatDeviceTest : WindowTestBase(), CompatDeviceTestInterface {
 
     private lateinit var sidecarCompat: SidecarCompat
@@ -73,6 +80,49 @@ public class SidecarCompatDeviceTest : WindowTestBase(), CompatDeviceTestInterfa
         }
     }
 
+    @Test
+    fun testWindowLayoutCallbackOnConfigChange() {
+        val testScope = TestCoroutineScope()
+        testScope.runBlockingTest {
+            val scenario = ActivityScenario.launch(TestConfigChangeHandlingActivity::class.java)
+            val callbackInterface = mock<ExtensionCallbackInterface>()
+            scenario.onActivity { activity ->
+                val windowToken = getActivityWindowToken(activity)
+                assertNotNull(windowToken)
+                sidecarCompat.setExtensionCallback(callbackInterface)
+                sidecarCompat.onWindowLayoutChangeListenerAdded(activity)
+                activity.resetLayoutCounter()
+                activity.requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT
+                activity.waitForLayout()
+            }
+            scenario.onActivity { activity ->
+                val windowToken = getActivityWindowToken(activity)
+                assertNotNull(windowToken)
+                val sidecarWindowLayoutInfo =
+                    sidecarCompat.sidecar!!.getWindowLayoutInfo(windowToken)
+                verify(callbackInterface, atLeastOnce()).onWindowLayoutChanged(
+                    any(),
+                    argThat(SidecarMatcher(sidecarWindowLayoutInfo))
+                )
+            }
+            scenario.onActivity { activity ->
+                activity.resetLayoutCounter()
+                activity.requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE
+                activity.waitForLayout()
+            }
+            scenario.onActivity { activity ->
+                val windowToken = getActivityWindowToken(activity)
+                assertNotNull(windowToken)
+                val updatedSidecarWindowLayoutInfo =
+                    sidecarCompat.sidecar!!.getWindowLayoutInfo(windowToken)
+                verify(callbackInterface, atLeastOnce()).onWindowLayoutChanged(
+                    any(),
+                    argThat(SidecarMatcher(updatedSidecarWindowLayoutInfo))
+                )
+            }
+        }
+    }
+
     private fun assumeExtensionV01() {
         val sidecarVersion = SidecarCompat.sidecarVersion
         assumeTrue(Version.VERSION_0_1 == sidecarVersion)

window/window/src/main/java/androidx/window/layout/SidecarCompat.kt

@@ -20,7 +20,9 @@ package androidx.window.layout
 
 import android.annotation.SuppressLint
 import android.app.Activity
+import android.content.ComponentCallbacks
 import android.content.Context
+import android.content.res.Configuration
 import android.os.IBinder
 import android.text.TextUtils
 import android.util.Log
@@ -51,6 +53,9 @@ internal class SidecarCompat @VisibleForTesting constructor(
     // Map of active listeners registered with #onWindowLayoutChangeListenerAdded() and not yet
     // removed by #onWindowLayoutChangeListenerRemoved().
     private val windowListenerRegisteredContexts = mutableMapOf<IBinder, Activity>()
+    // Map of activities registered to their component callbacks so we can keep track and
+    // remove when the activity is unregistered
+    private val componentCallbackMap = mutableMapOf<Activity, ComponentCallbacks>()
     private var extensionCallback: ExtensionCallbackInterface? = null
 
     constructor(context: Context) : this(
@@ -103,18 +108,49 @@ internal class SidecarCompat @VisibleForTesting constructor(
             sidecar?.onDeviceStateListenersChanged(false)
         }
         extensionCallback?.onWindowLayoutChanged(activity, getWindowLayoutInfo(activity))
+        registerConfigurationChangeListener(activity)
+    }
+
+    private fun registerConfigurationChangeListener(activity: Activity) {
+        // Only register a component callback if we haven't already as register
+        // may be called multiple times for the same activity
+        if (componentCallbackMap[activity] == null) {
+            // Create a configuration change observer to send updated WindowLayoutInfo
+            // when the configuration of the app changes: b/186647126
+            val configChangeObserver = object : ComponentCallbacks {
+                override fun onConfigurationChanged(newConfig: Configuration) {
+                    extensionCallback?.onWindowLayoutChanged(
+                        activity,
+                        getWindowLayoutInfo(activity)
+                    )
+                }
+
+                override fun onLowMemory() {
+                    return
+                }
+            }
+            componentCallbackMap[activity] = configChangeObserver
+            activity.registerComponentCallbacks(configChangeObserver)
+        }
     }
 
     override fun onWindowLayoutChangeListenerRemoved(activity: Activity) {
         val windowToken = getActivityWindowToken(activity) ?: return
         sidecar?.onWindowLayoutChangeListenerRemoved(windowToken)
+        unregisterComponentCallback(activity)
         val isLast = windowListenerRegisteredContexts.size == 1
         windowListenerRegisteredContexts.remove(windowToken)
         if (isLast) {
             sidecar?.onDeviceStateListenersChanged(true)
         }
     }
 
+    private fun unregisterComponentCallback(activity: Activity) {
+        val configChangeObserver = componentCallbackMap[activity]
+        activity.unregisterComponentCallbacks(configChangeObserver)
+        componentCallbackMap.remove(activity)
+    }
+
     @SuppressLint("BanUncheckedReflection")
     override fun validateExtensionInterface(): Boolean {
         return try {