Bug 1110039 - Part 4 - Hook new classes into the system. r=roc

The necessary modifications are the same as SelectionCarets. For
convenience, Touch/SelectionCarets will be disabled whenever
AccessibleCaret preference is enabled.

dom/base/nsFocusManager.cpp

@@ -8,6 +8,7 @@
 
 #include "nsFocusManager.h"
 
+#include "AccessibleCaretEventHub.h"
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsGkAtoms.h"
 #include "nsContentUtils.h"
@@ -1694,6 +1695,11 @@ nsFocusManager::Blur(nsPIDOMWindow* aWindowToClear,
     selectionCarets->NotifyBlur(aIsLeavingDocument || !mActiveWindow);
   }
 
+  nsRefPtr<AccessibleCaretEventHub> eventHub = presShell->GetAccessibleCaretEventHub();
+  if (eventHub) {
+    eventHub->NotifyBlur(aIsLeavingDocument || !mActiveWindow);
+  }
+
   // at this point, it is expected that this window will be still be
   // focused, but the focused content will be null, as it was cleared before
   // the event. If this isn't the case, then something else was focused during

layout/base/nsIPresShell.h

@@ -59,6 +59,7 @@ class nsCanvasFrame;
 class nsAString;
 class nsCaret;
 namespace mozilla {
+class AccessibleCaretEventHub;
 class TouchCaret;
 class SelectionCarets;
 } // namespace mozilla
@@ -808,6 +809,11 @@ public:
    */
   virtual mozilla::dom::Element* GetSelectionCaretsEndElement() const = 0;
 
+  /**
+   * Get the AccessibleCaretEventHub, if it exists. AddRefs it.
+   */
+  virtual already_AddRefed<mozilla::AccessibleCaretEventHub> GetAccessibleCaretEventHub() const = 0;
+
   /**
    * Get the caret, if it exists. AddRefs it.
    */

layout/base/nsPresShell.cpp

@@ -76,6 +76,7 @@
 #include "nsIPermissionManager.h"
 #include "nsIMozBrowserFrame.h"
 #include "nsCaret.h"
+#include "AccessibleCaretEventHub.h"
 #include "TouchCaret.h"
 #include "SelectionCarets.h"
 #include "nsIDOMHTMLDocument.h"
@@ -706,6 +707,7 @@ static uint32_t sNextPresShellId;
 static bool sPointerEventEnabled = true;
 static bool sTouchCaretEnabled = false;
 static bool sSelectionCaretEnabled = false;
+static bool sAccessibleCaretEnabled = false;
 static bool sBeforeAfterKeyboardEventEnabled = false;
 
 /* static */ bool
@@ -730,6 +732,17 @@ PresShell::SelectionCaretPrefEnabled()
   return sSelectionCaretEnabled;
 }
 
+/* static */ bool
+PresShell::AccessibleCaretEnabled()
+{
+  static bool initialized = false;
+  if (!initialized) {
+    Preferences::AddBoolVarCache(&sAccessibleCaretEnabled, "layout.accessiblecaret.enabled");
+    initialized = true;
+  }
+  return sAccessibleCaretEnabled;
+}
+
 /* static */ bool
 PresShell::BeforeAfterKeyboardEventEnabled()
 {
@@ -883,17 +896,21 @@ PresShell::Init(nsIDocument* aDocument,
   // before creating any frames.
   SetPreferenceStyleRules(false);
 
-  if (TouchCaretPrefEnabled()) {
+  if (TouchCaretPrefEnabled() && !AccessibleCaretEnabled()) {
     // Create touch caret handle
     mTouchCaret = new TouchCaret(this);
   }
 
-  if (SelectionCaretPrefEnabled()) {
+  if (SelectionCaretPrefEnabled() && !AccessibleCaretEnabled()) {
     // Create selection caret handle
     mSelectionCarets = new SelectionCarets(this);
     mSelectionCarets->Init();
   }
 
+  if (AccessibleCaretEnabled()) {
+    // Need to happen before nsFrameSelection has been set up.
+    mAccessibleCaretEventHub = new AccessibleCaretEventHub();
+  }
 
   mSelection = new nsFrameSelection();
 
@@ -1163,6 +1180,11 @@ PresShell::Destroy()
     mSelectionCarets = nullptr;
   }
 
+  if (mAccessibleCaretEventHub) {
+    mAccessibleCaretEventHub->Terminate();
+    mAccessibleCaretEventHub = nullptr;
+  }
+
   // release our pref style sheet, if we have one still
   ClearPreferenceStyleRules();
 
@@ -1907,6 +1929,11 @@ PresShell::Initialize(nscoord aWidth, nscoord aHeight)
       mFrameConstructor->EndUpdate();
     }
 
+    // Initialize after nsCanvasFrame is created.
+    if (mAccessibleCaretEventHub) {
+      mAccessibleCaretEventHub->Init(this);
+    }
+
     // nsAutoScriptBlocker going out of scope may have killed us too
     NS_ENSURE_STATE(!mHaveShutDown);
 
@@ -2214,6 +2241,12 @@ already_AddRefed<SelectionCarets> PresShell::GetSelectionCarets() const
   return selectionCaret.forget();
 }
 
+already_AddRefed<AccessibleCaretEventHub> PresShell::GetAccessibleCaretEventHub() const
+{
+  nsRefPtr<AccessibleCaretEventHub> eventHub = mAccessibleCaretEventHub;
+  return eventHub.forget();
+}
+
 void PresShell::SetCaret(nsCaret *aNewCaret)
 {
   mCaret = aNewCaret;
@@ -7253,6 +7286,28 @@ PresShell::HandleEvent(nsIFrame* aFrame,
     }
   }
 
+  if (AccessibleCaretEnabled()) {
+    // We have to target the focus window because regardless of where the
+    // touch goes, we want to access the copy paste manager.
+    nsCOMPtr<nsPIDOMWindow> window = GetFocusedDOMWindowInOurWindow();
+    nsCOMPtr<nsIDocument> retargetEventDoc =
+      window ? window->GetExtantDoc() : nullptr;
+    nsCOMPtr<nsIPresShell> presShell =
+      retargetEventDoc ? retargetEventDoc->GetShell() : nullptr;
+
+    nsRefPtr<AccessibleCaretEventHub> eventHub =
+      presShell ? presShell->GetAccessibleCaretEventHub() : nullptr;
+    if (eventHub) {
+      *aEventStatus = eventHub->HandleEvent(aEvent);
+      if (*aEventStatus == nsEventStatus_eConsumeNoDefault) {
+        // If the event is consumed, cancel APZC panning by setting
+        // mMultipleActionsPrevented.
+        aEvent->mFlags.mMultipleActionsPrevented = true;
+        return NS_OK;
+      }
+    }
+  }
+
   if (sPointerEventEnabled) {
     UpdateActivePointerState(aEvent);
   }

layout/base/nsPresShell.h

@@ -77,6 +77,8 @@ public:
   // Selection caret preference
   static bool SelectionCaretPrefEnabled();
 
+  static bool AccessibleCaretEnabled();
+
   // BeforeAfterKeyboardEvent preference
   static bool BeforeAfterKeyboardEventEnabled();
 
@@ -240,6 +242,9 @@ public:
   virtual already_AddRefed<mozilla::SelectionCarets> GetSelectionCarets() const override;
   virtual mozilla::dom::Element* GetSelectionCaretsStartElement() const override;
   virtual mozilla::dom::Element* GetSelectionCaretsEndElement() const override;
+
+  virtual already_AddRefed<mozilla::AccessibleCaretEventHub> GetAccessibleCaretEventHub() const override;
+
   // caret handling
   virtual already_AddRefed<nsCaret> GetCaret() const override;
   NS_IMETHOD SetCaretEnabled(bool aInEnable) override;
@@ -811,6 +816,7 @@ protected:
   // TouchCaret
   nsRefPtr<mozilla::TouchCaret> mTouchCaret;
   nsRefPtr<mozilla::SelectionCarets> mSelectionCarets;
+  nsRefPtr<mozilla::AccessibleCaretEventHub> mAccessibleCaretEventHub;
 
   // This timer controls painting suppression.  Until it fires
   // or all frames are constructed, we won't paint anything but

layout/generic/nsSelection.cpp

@@ -54,6 +54,9 @@ static NS_DEFINE_CID(kFrameTraversalCID, NS_FRAMETRAVERSAL_CID);
 #include "TouchCaret.h"
 #include "SelectionCarets.h"
 
+#include "AccessibleCaretEventHub.h"
+#include "AccessibleCaretManager.h"
+
 #include "mozilla/MouseEvents.h"
 #include "mozilla/TextEvents.h"
 
@@ -819,6 +822,14 @@ nsFrameSelection::Init(nsIPresShell *aShell, nsIContent *aLimiter)
       mDomSelections[index]->AddSelectionListener(selectionCarets);
     }
   }
+
+  nsRefPtr<AccessibleCaretEventHub> eventHub = mShell->GetAccessibleCaretEventHub();
+  if (eventHub) {
+    int8_t index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
+    if (mDomSelections[index]) {
+      mDomSelections[index]->AddSelectionListener(eventHub);
+    }
+  }
 }
 
 nsresult
@@ -3225,6 +3236,12 @@ nsFrameSelection::DisconnectFromPresShell()
     mDomSelections[index]->RemoveSelectionListener(selectionCarets);
   }
 
+  nsRefPtr<AccessibleCaretEventHub> eventHub = mShell->GetAccessibleCaretEventHub();
+  if (eventHub) {
+    int8_t index = GetIndexFromSelectionType(nsISelectionController::SELECTION_NORMAL);
+    mDomSelections[index]->RemoveSelectionListener(eventHub);
+  }
+
   StopAutoScrollTimer();
   for (int32_t i = 0; i < nsISelectionController::NUM_SELECTIONTYPES; i++) {
     mDomSelections[i]->Clear(nullptr);

modules/libpref/init/all.js

@@ -4553,6 +4553,13 @@ pref("selectioncaret.inflatesize.threshold", 40);
 // Selection carets will fall-back to internal LongTap detector.
 pref("selectioncaret.detects.longtap", true);
 
+// New implementation to unify touch-caret and selection-carets.
+pref("layout.accessiblecaret.enabled", false);
+
+// Timeout in milliseconds to hide the accessiblecaret under cursor mode while
+// no one touches it. Set the value to 0 to disable this feature.
+pref("layout.accessiblecaret.timeout_ms", 3000);
+
 // Wakelock is disabled by default.
 pref("dom.wakelock.enabled", false);