[fenix] Bug 1804377 - Avoid unwanted dismissal of tab history.

app/src/main/java/org/mozilla/fenix/HomeActivity.kt

@@ -89,6 +89,7 @@ import org.mozilla.fenix.ext.alreadyOnDestination
 import org.mozilla.fenix.ext.areNotificationsEnabledSafe
 import org.mozilla.fenix.ext.breadcrumb
 import org.mozilla.fenix.ext.components
+import org.mozilla.fenix.ext.hasTopDestination
 import org.mozilla.fenix.ext.nav
 import org.mozilla.fenix.ext.setNavigationIcon
 import org.mozilla.fenix.ext.settings
@@ -133,6 +134,7 @@ import org.mozilla.fenix.settings.search.EditCustomSearchEngineFragmentDirection
 import org.mozilla.fenix.settings.studies.StudiesFragmentDirections
 import org.mozilla.fenix.settings.wallpaper.WallpaperSettingsFragmentDirections
 import org.mozilla.fenix.share.AddNewDeviceFragmentDirections
+import org.mozilla.fenix.tabhistory.TabHistoryDialogFragment
 import org.mozilla.fenix.tabstray.TabsTrayFragment
 import org.mozilla.fenix.tabstray.TabsTrayFragmentDirections
 import org.mozilla.fenix.theme.DefaultThemeManager
@@ -715,9 +717,18 @@ open class HomeActivity : LocaleAwareAppCompatActivity(), NavHostActivity {
         return super.onKeyDown(keyCode, event)
     }
 
-    final override fun onKeyUp(keyCode: Int, event: KeyEvent?): Boolean {
+    final override fun onKeyUp(keyCode: Int, event: KeyEvent): Boolean {
         if (shouldUseCustomBackLongPress() && keyCode == KeyEvent.KEYCODE_BACK) {
             backLongPressJob?.cancel()
+
+            // check if the key has been pressed for longer than the time needed for a press to turn into a long press
+            // and if tab history is already visible we do not want to dismiss it.
+            if (event.eventTime - event.downTime >= ViewConfiguration.getLongPressTimeout() &&
+                navHost.navController.hasTopDestination(TabHistoryDialogFragment.NAME)
+            ) {
+                // returning true avoids further processing of the KeyUp event and avoids dismissing tab history.
+                return true
+            }
         }
         return super.onKeyUp(keyCode, event)
     }

app/src/main/java/org/mozilla/fenix/ext/NavController.kt

@@ -4,6 +4,7 @@
 
 package org.mozilla.fenix.ext
 
+import android.annotation.SuppressLint
 import androidx.annotation.IdRes
 import androidx.navigation.NavController
 import androidx.navigation.NavDirections
@@ -34,3 +35,14 @@ fun NavController.navigateSafe(
         this.navigate(directions)
     }
 }
+
+/**
+ * Checks if the Fragment with a [fragmentClassName] is on top of the back queue.
+ */
+@SuppressLint("RestrictedApi")
+fun NavController.hasTopDestination(fragmentClassName: String): Boolean {
+    return this.backQueue.lastOrNull()?.destination?.displayName?.contains(
+        fragmentClassName,
+        true,
+    ) == true
+}

app/src/main/java/org/mozilla/fenix/tabhistory/TabHistoryDialogFragment.kt

@@ -67,5 +67,7 @@ class TabHistoryDialogFragment : BottomSheetDialogFragment() {
 
     companion object {
         const val EXTRA_SESSION_ID = "activeSessionId"
+        val NAME: String = TabHistoryDialogFragment::class.java.canonicalName?.substringAfterLast('.')
+            ?: TabHistoryDialogFragment::class.java.simpleName
     }
 }