Add additional tests for AndroidX Navigation Interop, change the way …

…that the AndroidX Navigation Interop is executed

enro-core/src/main/java/dev/enro/core/fragment/DefaultFragmentExecutor.kt

@@ -104,8 +104,6 @@ object DefaultFragmentExecutor : NavigationExecutor<Any, Fragment, NavigationKey
     }
 
     override fun close(context: NavigationContext<out Fragment>) {
-        if (interceptCloseInstructionForAndroidxNavigation(context)) return
-
         if(!tryExecutePendingTransitions(context.fragment.parentFragmentManager)) {
             mainThreadHandler.post {
                 /*

enro-core/src/main/java/dev/enro/core/fragment/AndroidxNavigationInterop.kt → enro-core/src/main/java/dev/enro/core/internal/handle/AndroidxNavigationInterop.kt

@@ -1,29 +1,36 @@
 package dev.enro.core.fragment
 
+import androidx.activity.OnBackPressedCallback
 import androidx.fragment.app.Fragment
 import androidx.navigation.fragment.NavHostFragment
 import dev.enro.core.NavigationContext
-import dev.enro.core.fragment
+import dev.enro.core.activity
 
 /**
  * In applications that contain both AndroidX Navigation and Enro, the back pressed behaviour
  * that is set by the NavigationHandleViewModel takes precedence over the back pressed behaviours that
  * are set by AndroidX Navigation.
  *
- * This method checks whether or not a given NavigationContext<out Fragment> is a part of the AndroidX Navigation,
+ * This method checks whether or not a given NavigationContext<*> is a part of the AndroidX Navigation,
  * by checking whether or not the parent fragment is a NavHostFragment. If we see that it is a NavHostFragment,
- * we'll execute popBackStack (which is the same behaviour the back pressed behaviour set by AndroidX Navigation),
- * and then return true.
+ * we'll disable the back pressed callback, repeat the activity.onBackPressed, and then return true
  *
- * If we decide that the NavigationContext<out Fragment> does **not** belong to AndroidX Navigation, and
+ * If we decide that the NavigationContext<*> does **not** belong to AndroidX Navigation, and
  * is either part of Enro, or not part of any navigation framework, then we return false, to indicate that no
  * action was performed.
  */
-internal fun interceptCloseInstructionForAndroidxNavigation(context: NavigationContext<out Fragment>): Boolean {
+internal fun interceptBackPressForAndroidxNavigation(
+    backPressedCallback: OnBackPressedCallback,
+    context: NavigationContext<*>,
+): Boolean {
+    val fragment = context.contextReference as? Fragment ?: return false
     if (!isAndroidxNavigationOnTheClasspath) return false
-    val parent = context.fragment.parentFragment
+
+    val parent = fragment.parentFragment
     if (parent is NavHostFragment) {
-        parent.navController.popBackStack()
+        backPressedCallback.isEnabled = false
+        context.activity.onBackPressed()
+        backPressedCallback.isEnabled = true
         return true
     }
     return false

enro-core/src/main/java/dev/enro/core/internal/handle/NavigationHandleViewModel.kt

@@ -1,15 +1,12 @@
 package dev.enro.core.internal.handle
 
 import android.os.Bundle
-import android.os.Handler
-import android.os.Looper
-import android.util.Log
-import androidx.activity.OnBackPressedCallback
-import androidx.fragment.app.Fragment
+import androidx.activity.addCallback
 import androidx.fragment.app.FragmentActivity
 import androidx.lifecycle.*
 import dev.enro.core.*
 import dev.enro.core.controller.NavigationController
+import dev.enro.core.fragment.interceptBackPressForAndroidxNavigation
 import dev.enro.core.internal.NoNavigationKey
 
 internal open class NavigationHandleViewModel(
@@ -21,12 +18,13 @@ internal open class NavigationHandleViewModel(
 
     internal val hasKey get() = instruction.navigationKey !is NoNavigationKey
 
-    override val key: NavigationKey get() {
-        if(instruction.navigationKey is NoNavigationKey) throw IllegalStateException(
-            "The navigation handle for the context ${navigationContext?.contextReference} has no NavigationKey"
-        )
-        return instruction.navigationKey
-    }
+    override val key: NavigationKey
+        get() {
+            if (instruction.navigationKey is NoNavigationKey) throw IllegalStateException(
+                "The navigation handle for the context ${navigationContext?.contextReference} has no NavigationKey"
+            )
+            return instruction.navigationKey
+        }
     override val id: String get() = instruction.instructionId
     override val additionalData: Bundle get() = instruction.additionalData
 
@@ -66,8 +64,10 @@ internal open class NavigationHandleViewModel(
 
     private fun registerOnBackPressedListener(context: NavigationContext<out Any>) {
         if (context is ActivityContext<out FragmentActivity>) {
-            context.activity.addOnBackPressedListener {
-                context.leafContext().getNavigationHandleViewModel().requestClose()
+            context.activity.onBackPressedDispatcher.addCallback(this) {
+                val leafContext = context.leafContext()
+                if (interceptBackPressForAndroidxNavigation(this, leafContext)) return@addCallback
+                leafContext.getNavigationHandleViewModel().requestClose()
             }
         }
     }
@@ -110,21 +110,12 @@ internal open class NavigationHandleViewModel(
     }
 }
 
-
 private fun Lifecycle.onEvent(on: Lifecycle.Event, block: () -> Unit) {
     addObserver(object : LifecycleEventObserver {
         override fun onStateChanged(source: LifecycleOwner, event: Lifecycle.Event) {
-            if(on == event) {
+            if (on == event) {
                 block()
             }
         }
     })
-}
-
-private fun FragmentActivity.addOnBackPressedListener(block: () -> Unit) {
-    onBackPressedDispatcher.addCallback(this, object : OnBackPressedCallback(true) {
-        override fun handleOnBackPressed() {
-            block()
-        }
-    })
 }

enro/src/androidTest/java/dev/enro/core/AndroidxNavigationInteropTest.kt

@@ -1,23 +1,27 @@
 package dev.enro.core
 
+import android.content.Intent
 import android.os.Bundle
 import android.view.View
 import android.widget.LinearLayout
 import android.widget.TextView
+import androidx.activity.addCallback
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.os.bundleOf
 import androidx.core.view.children
 import androidx.navigation.fragment.findNavController
 import androidx.test.core.app.ActivityScenario
 import androidx.test.espresso.Espresso
+import androidx.test.platform.app.InstrumentationRegistry
 import dev.enro.TestFragment
 import dev.enro.expectFragment
+import dev.enro.expectNoActivity
 import org.junit.Test
 
 class AndroidxNavigationInteropTest {
 
     @Test
-    fun whenBackButtonIsPressed_thenJetpackNavigationReceivesBackButtonPress() {
+    fun givenMultipleAndroidxNavigationFragments_whenBackButtonIsPressed_thenAndroidxNavigationReceivesBackButtonPress() {
         val scenario = ActivityScenario.launch(JetpackNavigationActivity::class.java)
 
         expectFragment<JetpackNavigationFragment> {
@@ -43,9 +47,38 @@ class AndroidxNavigationInteropTest {
         }
     }
 
+    @Test
+    fun givenSingleAndroidxNavigationFragment_whenNavigationBackButtonIsPressed_thenActivityIsClosed() {
+        val scenario = ActivityScenario.launch(JetpackNavigationActivity::class.java)
+        expectFragment<JetpackNavigationFragment> {
+            it.navigationArgument == 0
+        }
+        scenario.onActivity { it.onBackPressed() }
+        expectNoActivity()
+    }
+
+    @Test
+    fun givenActivityIsLaunched_andFragmentHasCustomBackNavigation_whenBackButtonIsPressed_thenCustomNavigationIsExecuted() {
+        val scenario = ActivityScenario.launch<JetpackNavigationActivity>(
+            Intent(InstrumentationRegistry.getInstrumentation().context, JetpackNavigationActivity::class.java).apply {
+                putExtra("shouldRegisterBackNavigation", true)
+            }
+        )
+        expectFragment<JetpackNavigationFragment> {
+            it.navigationArgument == 0
+        }
+        Espresso.pressBack()
+        expectFragment<JetpackNavigationFragment> {
+            it.executedCustomBackPressed
+        }
+    }
 }
 
 internal class JetpackNavigationActivity : AppCompatActivity() {
+    val shouldRegisterBackNavigation by lazy {
+        intent.getBooleanExtra("shouldRegisterBackNavigation", false)
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(dev.enro.test.R.layout.jetpack_navigation_activity_layout)
@@ -57,6 +90,18 @@ internal class JetpackNavigationFragment : TestFragment() {
         requireArguments().getInt("argument", 0)
     }
 
+    var executedCustomBackPressed = false
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        val activity = requireActivity() as JetpackNavigationActivity
+        if (activity.shouldRegisterBackNavigation && navigationArgument == 0) {
+            activity.onBackPressedDispatcher.addCallback(this) {
+                executedCustomBackPressed = true
+            }
+        }
+    }
+
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         val layout = requireView() as LinearLayout
         val title = layout.children.first() as TextView

enro/src/androidTest/res/navigation/navigation.xml

@@ -21,6 +21,6 @@
                 app:argType="integer"
                 android:defaultValue="0" />
         </action>
-        >
+
     </fragment>
 </navigation>