From 9c9d930760fe26f7600dcfc657b1a4f68794ec56 Mon Sep 17 00:00:00 2001
From: reuk <reuk@users.noreply.github.com>
Date: Mon, 23 May 2022 19:59:57 +0100
Subject: [PATCH] Android:  Fix a couple of accessibility-related crashes

These crashes could be seen in the DemoRunner when selecting items in
nested PopupMenu windows.
---
 .../accessibility/juce_AccessibilityHandler.cpp      |  1 -
 .../juce_gui_basics/components/juce_Component.cpp    | 12 ++++++++++++
 modules/juce_gui_basics/menus/juce_PopupMenu.cpp     |  5 +++--
 .../accessibility/juce_android_Accessibility.cpp     |  9 ++++++++-
 .../widgets/juce_ToolbarItemComponent.cpp            |  2 +-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/modules/juce_gui_basics/accessibility/juce_AccessibilityHandler.cpp b/modules/juce_gui_basics/accessibility/juce_AccessibilityHandler.cpp
index 8dbf22da71..df14dffd2f 100644
--- a/modules/juce_gui_basics/accessibility/juce_AccessibilityHandler.cpp
+++ b/modules/juce_gui_basics/accessibility/juce_AccessibilityHandler.cpp
@@ -63,7 +63,6 @@ AccessibilityHandler::AccessibilityHandler (Component& comp,
       interfaces (std::move (interfacesIn)),
       nativeImpl (createNativeImpl (*this))
 {
-    notifyAccessibilityEventInternal (*this, InternalAccessibilityEvent::elementCreated);
 }
 
 AccessibilityHandler::~AccessibilityHandler()
diff --git a/modules/juce_gui_basics/components/juce_Component.cpp b/modules/juce_gui_basics/components/juce_Component.cpp
index 77c1a37e97..fcc54c5c9d 100644
--- a/modules/juce_gui_basics/components/juce_Component.cpp
+++ b/modules/juce_gui_basics/components/juce_Component.cpp
@@ -3308,6 +3308,18 @@ AccessibilityHandler* Component::getAccessibilityHandler()
         || accessibilityHandler->getTypeIndex() != std::type_index (typeid (*this)))
     {
         accessibilityHandler = createAccessibilityHandler();
+
+        // On Android, notifying that an element was created can cause the system to request
+        // the accessibility node info for the new element. If we're not careful, this will lead
+        // to recursive calls, as each time an element is created, new node info will be requested,
+        // causing an element to be created, causing a new info request...
+        // By assigning the accessibility handler before notifying the system that an element was
+        // created, the if() predicate above should evaluate to false on recursive calls,
+        // terminating the recursion.
+        if (accessibilityHandler != nullptr)
+            notifyAccessibilityEventInternal (*accessibilityHandler, InternalAccessibilityEvent::elementCreated);
+        else
+            jassertfalse; // createAccessibilityHandler must return non-null
     }
 
     return accessibilityHandler.get();
diff --git a/modules/juce_gui_basics/menus/juce_PopupMenu.cpp b/modules/juce_gui_basics/menus/juce_PopupMenu.cpp
index d004782804..d0633a3e6b 100644
--- a/modules/juce_gui_basics/menus/juce_PopupMenu.cpp
+++ b/modules/juce_gui_basics/menus/juce_PopupMenu.cpp
@@ -87,7 +87,7 @@ struct HeaderItemComponent  : public PopupMenu::CustomComponent
 
     std::unique_ptr<AccessibilityHandler> createAccessibilityHandler() override
     {
-        return nullptr;
+        return createIgnoredAccessibilityHandler (*this);
     }
 
     const Options& options;
@@ -275,7 +275,8 @@ private:
 
     std::unique_ptr<AccessibilityHandler> createAccessibilityHandler() override
     {
-        return item.isSeparator ? nullptr : std::make_unique<ItemAccessibilityHandler> (*this);
+        return item.isSeparator ? createIgnoredAccessibilityHandler (*this)
+                                : std::make_unique<ItemAccessibilityHandler> (*this);
     }
 
     //==============================================================================
diff --git a/modules/juce_gui_basics/native/accessibility/juce_android_Accessibility.cpp b/modules/juce_gui_basics/native/accessibility/juce_android_Accessibility.cpp
index 53ae2a67f3..637cfbd8a8 100644
--- a/modules/juce_gui_basics/native/accessibility/juce_android_Accessibility.cpp
+++ b/modules/juce_gui_basics/native/accessibility/juce_android_Accessibility.cpp
@@ -481,10 +481,15 @@ public:
 
             case ACTION_CLICK:
             {
+                // Invoking the action may delete this handler
+                const WeakReference<AccessibilityNativeHandle> savedHandle { this };
+
                 if ((accessibilityHandler.getCurrentState().isCheckable() && accessibilityHandler.getActions().invoke (AccessibilityActionType::toggle))
                     || accessibilityHandler.getActions().invoke (AccessibilityActionType::press))
                 {
-                    sendAccessibilityEventImpl (accessibilityHandler, TYPE_VIEW_CLICKED, 0);
+                    if (savedHandle != nullptr)
+                        sendAccessibilityEventImpl (accessibilityHandler, TYPE_VIEW_CLICKED, 0);
+
                     return true;
                 }
 
@@ -742,6 +747,8 @@ private:
 
     //==============================================================================
     JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AccessibilityNativeHandle)
+
+    JUCE_DECLARE_WEAK_REFERENCEABLE (AccessibilityNativeHandle)
 };
 
 std::unordered_map<int, AccessibilityHandler*> AccessibilityNativeHandle::virtualViewIdMap;
diff --git a/modules/juce_gui_basics/widgets/juce_ToolbarItemComponent.cpp b/modules/juce_gui_basics/widgets/juce_ToolbarItemComponent.cpp
index e42f0e6195..e871094abb 100644
--- a/modules/juce_gui_basics/widgets/juce_ToolbarItemComponent.cpp
+++ b/modules/juce_gui_basics/widgets/juce_ToolbarItemComponent.cpp
@@ -247,7 +247,7 @@ std::unique_ptr<AccessibilityHandler> ToolbarItemComponent::createAccessibilityH
                                       && itemId != ToolbarItemFactory::flexibleSpacerId);
 
     if (! shouldItemBeAccessible)
-        return nullptr;
+        return createIgnoredAccessibilityHandler (*this);
 
     return std::make_unique<ButtonAccessibilityHandler> (*this, AccessibilityRole::button);
 }