For #11851: Close tab tray when last tab closed (#12615)

app/src/main/java/org/mozilla/fenix/tabtray/TabTrayController.kt

@@ -117,6 +117,7 @@ class DefaultTabTrayController(
         }
 
         showUndoSnackbar(snackbarMessage, snapshot)
+        dismissTabTray()
     }
 
     @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)

app/src/main/java/org/mozilla/fenix/tabtray/TabTrayDialogFragment.kt

@@ -38,6 +38,7 @@ import org.mozilla.fenix.components.FenixSnackbar
 import org.mozilla.fenix.components.TabCollectionStorage
 import org.mozilla.fenix.components.metrics.Event
 import org.mozilla.fenix.ext.components
+import org.mozilla.fenix.ext.getRootView
 import org.mozilla.fenix.ext.requireComponents
 import org.mozilla.fenix.ext.settings
 import org.mozilla.fenix.utils.allowUndo
@@ -204,19 +205,32 @@ class TabTrayDialogFragment : AppCompatDialogFragment() {
             getString(R.string.snackbar_tab_closed)
         }
 
-        view?.tabLayout?.let {
-            viewLifecycleOwner.lifecycleScope.allowUndo(
-                it,
-                snackbarMessage,
-                getString(R.string.snackbar_deleted_undo),
-                {
-                    sessionManager.add(snapshot.session, isSelected, engineSessionState = state)
-                    tabTrayView.scrollToTab(snapshot.session.id)
-                },
-                operation = { },
-                elevation = ELEVATION,
-                anchorView = snackbarAnchor
-            )
+        // Check if this is the last tab of this session type
+        val isLastOpenTab = sessionManager.sessions.filter { snapshot.session.private }.size == 1
+        val rootView = if (isLastOpenTab) { requireActivity().getRootView()!! } else { requireView().tabLayout }
+        val anchorView = if (isLastOpenTab) { null } else { snackbarAnchor }
+
+        requireActivity().lifecycleScope.allowUndo(
+            rootView,
+            snackbarMessage,
+            getString(R.string.snackbar_deleted_undo),
+            {
+                sessionManager.add(snapshot.session, isSelected, engineSessionState = state)
+                _tabTrayView?.scrollToTab(snapshot.session.id)
+            },
+            operation = { },
+            elevation = ELEVATION,
+            paddedForBottomToolbar = isLastOpenTab,
+            anchorView = anchorView
+        )
+
+        dismissTabTrayIfNecessary()
+    }
+
+    private fun dismissTabTrayIfNecessary() {
+        if (requireComponents.core.sessionManager.sessions.size == 1) {
+            findNavController().popBackStack(R.id.homeFragment, false)
+            dismissAllowingStateLoss()
         }
     }
 
@@ -250,19 +264,20 @@ class TabTrayDialogFragment : AppCompatDialogFragment() {
     }
 
     private fun showUndoSnackbar(snackbarMessage: String, snapshot: SessionManager.Snapshot) {
-        view?.let {
-            viewLifecycleOwner.lifecycleScope.allowUndo(
-                it,
-                snackbarMessage,
-                getString(R.string.snackbar_deleted_undo),
-                {
-                    context?.components?.core?.sessionManager?.restore(snapshot)
-                },
-                operation = { },
-                elevation = ELEVATION,
-                anchorView = snackbarAnchor
-            )
-        }
+        // Warning: removing this definition and using it directly in the onCancel block will fail silently.
+        val sessionManager = view?.context?.components?.core?.sessionManager
+
+        requireActivity().lifecycleScope.allowUndo(
+            requireActivity().getRootView()!!,
+            snackbarMessage,
+            getString(R.string.snackbar_deleted_undo),
+            {
+                sessionManager?.restore(snapshot)
+            },
+            operation = { },
+            elevation = ELEVATION,
+            paddedForBottomToolbar = true
+        )
     }
 
     private fun showCollectionSnackbar(tabSize: Int, isNewCollection: Boolean = false) {

app/src/main/java/org/mozilla/fenix/utils/Undo.kt

@@ -5,10 +5,12 @@
 package org.mozilla.fenix.utils
 
 import android.view.View
+import androidx.appcompat.widget.ContentFrameLayout
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import org.mozilla.fenix.R
 import org.mozilla.fenix.components.FenixSnackbar
 import org.mozilla.fenix.ext.settings
 import java.util.concurrent.atomic.AtomicBoolean
@@ -37,7 +39,8 @@ fun CoroutineScope.allowUndo(
     onCancel: suspend () -> Unit = {},
     operation: suspend () -> Unit,
     anchorView: View? = null,
-    elevation: Float? = null
+    elevation: Float? = null,
+    paddedForBottomToolbar: Boolean = false
 ) {
     // By using an AtomicBoolean, we achieve memory effects of reading and
     // writing a volatile variable.
@@ -63,6 +66,30 @@ fun CoroutineScope.allowUndo(
             snackbar.view.elevation = it
         }
 
+        val shouldUseBottomToolbar = view.context.settings().shouldUseBottomToolbar
+        val toolbarHeight = view.context.resources
+            .getDimensionPixelSize(R.dimen.browser_toolbar_height)
+
+        snackbar.view.setPadding(
+            0,
+            0,
+            0,
+            if (
+                paddedForBottomToolbar &&
+                shouldUseBottomToolbar &&
+                // If the view passed in is a ContentFrameLayout, it does not matter
+                // if the user has a dynamicBottomToolbar or not, as the Android system
+                // can't intelligently position the snackbar on the upper most view.
+                // Ideally we should not pass ContentFrameLayout in, but it's the only
+                // way to display snackbars through a fragment transition.
+                view is ContentFrameLayout
+            ) {
+                toolbarHeight
+            } else {
+                0
+            }
+        )
+
         snackbar.show()
 
         // Wait a bit, and if user didn't request cancellation, proceed with