Extract touch handling logic from EventHandler

third_party/WebKit/Source/core/input/PointerEventManager.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PointerEventManager_h
 #define PointerEventManager_h
 
 #include "core/CoreExport.h"
 #include "core/events/PointerEvent.h"
 #include "core/events/PointerEventFactory.h"
+#include "core/input/TouchEventManager.h"
 #include "public/platform/WebInputEventResult.h"
 #include "public/platform/WebPointerProperties.h"
 #include "wtf/Allocator.h"
 #include "wtf/HashMap.h"
 
 namespace blink {
 
+class LocalFrame;
 
 // This class takes care of dispatching all pointer events and keeps track of
 // properties of active pointer events.
 class CORE_EXPORT PointerEventManager {
     DISALLOW_NEW();
 public:
-    PointerEventManager();
+    explicit PointerEventManager(LocalFrame*);
     ~PointerEventManager();
     DECLARE_TRACE();
 
     WebInputEventResult sendMousePointerEvent(
         Node*, const AtomicString& type,
         int clickCount, const PlatformMouseEvent&,
         Node* relatedTarget,
         AbstractView*,
         Node* lastNodeUnderMouse);
 
-    // Returns whether the event is consumed or not
-    WebInputEventResult sendTouchPointerEvent(
-        EventTarget*,
-        const PlatformTouchPoint&, PlatformEvent::Modifiers,
-        const double width, const double height,
-        const double clientX, const double clientY);
-
-    // Inhibits firing of touch-type PointerEvents until unblocked by unblockTouchPointers(). Also
-    // sends pointercancels for existing touch-type PointerEvents.
-    // See: www.w3.org/TR/pointerevents/#declaring-candidate-regions-for-default-touch-behaviors
-    void blockTouchPointers();
-
-    // Enables firing of touch-type PointerEvents after they were inhibited by blockTouchPointers().
-    void unblockTouchPointers();
+    WebInputEventResult handleTouchEvents(
+        const PlatformTouchEvent&);
 
     // Sends node transition events mouseout/leave/over/enter to the
     // corresponding targets. This function sends pointerout/leave/over/enter
     // only when isFrameBoundaryTransition is true which indicates the
     // transition is over the document boundary and not only the elements border
     // inside the document. If isFrameBoundaryTransition is false,
     // then the event is a compatibility event like those created by touch
     // and in that case the corresponding pointer events will be handled by
     // sendTouchPointerEvent for example and there is no need to send pointer
     // transition events. Note that normal mouse events (e.g. mousemove/down/up)
     // and their corresponding transition events will be handled altogether by
     // sendMousePointerEvent function.
     void sendMouseAndPossiblyPointerNodeTransitionEvents(
         Node* exitedNode,
         Node* enteredNode,
         const PlatformMouseEvent&,
         AbstractView*, bool isFrameBoundaryTransition);
 
-    // Clear all the existing ids.
+    // Resets the internal state of this object.
     void clear();
 
     void elementRemoved(EventTarget*);
     void setPointerCapture(int, EventTarget*);
     void releasePointerCapture(int, EventTarget*);
-    bool isActive(const int);
-    WebPointerProperties::PointerType getPointerEventType(const int);
+    bool isActive(const int) const;
+    WebPointerProperties::PointerType getPointerEventType(const int) const;
+
+    // Returns whether there is any touch on the screen.
+    bool isAnyTouchActive() const;
 
 private:
-    typedef HeapHashMap<int, Member<EventTarget>> PointerCapturingMap;
+    typedef HeapHashMap<int, Member<EventTarget>, WTF::IntHash<int>,
+        WTF::UnsignedWithZeroKeyHashTraits<int>> PointerCapturingMap;
     class EventTargetAttributes {
         DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
     public:
         DEFINE_INLINE_TRACE()
         {
             visitor->trace(target);
         }
         Member<EventTarget> target;
         bool hasRecievedOverEvent;
         EventTargetAttributes()
         : target(nullptr)
         , hasRecievedOverEvent(false) {}
         EventTargetAttributes(EventTarget* target,
             bool hasRecievedOverEvent)
         : target(target)
         , hasRecievedOverEvent(hasRecievedOverEvent) {}
     };
 
+    // Inhibits firing of touch-type PointerEvents until unblocked by unblockTouchPointers(). Also
+    // sends pointercancels for existing touch-type PointerEvents.
+    // See: www.w3.org/TR/pointerevents/#declaring-candidate-regions-for-default-touch-behaviors
+    void blockTouchPointers();
+
+    // Enables firing of touch-type PointerEvents after they were inhibited by blockTouchPointers().
+    void unblockTouchPointers();
+
+    void dispatchTouchPointerEvents(

[dtapuska, 2016/04/27 17:07:04]

Is it possible for HeapVector to be const?

I'm not entirely sure because you load structs from it.

At very worst case this will need a comment indicating it isn't an output
parameter; but const is likely better. You might need to change the iterator to
be a const auto&

[Navid Zolghadr, 2016/04/28 15:13:11]

It is kind of an output parameter in the sense that some of the fields are being
set (i.e. consumed bit).

[dtapuska, 2016/04/29 14:56:54]

Can we add a comment to the file describing what it does then? ie; it dispatches
the touch events and will adjust the heap vector under X conditions... just
because it isn't obvious.

+        const PlatformTouchEvent&, HeapVector<TouchEventManager::TouchInfo>&);
+
+    // Returns whether the event is consumed or not.
+    WebInputEventResult sendTouchPointerEvent(
+        EventTarget*, PointerEvent*);
+
     void sendNodeTransitionEvents(
         EventTarget* exitedTarget,
         EventTarget* enteredTarget,
         PointerEvent*,
         const PlatformMouseEvent& = PlatformMouseEvent(),
         bool sendMouseEvent = false);
     void setNodeUnderPointer(PointerEvent*,
         EventTarget*, bool sendEvent = true);
 
     // Returns whether the pointer capture is changed. In this case this
@@ skipping 22 matching lines @@
     EventTarget* getEffectiveTargetForPointerEvent(
         EventTarget*, int);
     EventTarget* getCapturingNode(int);
     void removePointer(PointerEvent*);
     WebInputEventResult dispatchPointerEvent(
         EventTarget*,
         PointerEvent*,
         bool checkForListener = false);
     void releasePointerCapture(int);
 
+    // NOTE: If adding a new field to this class please ensure that it is
+    // cleared in |PointerEventManager::clear()|.
+
+    const Member<LocalFrame> m_frame;
+
     // Prevents firing mousedown, mousemove & mouseup in-between a canceled pointerdown and next pointerup/pointercancel.
     // See "PREVENT MOUSE EVENT flag" in the spec:
     //   https://w3c.github.io/pointerevents/#compatibility-mapping-with-mouse-events
     bool m_preventMouseEventForPointerType[static_cast<size_t>(WebPointerProperties::PointerType::LastEntry) + 1];
 
     // Set upon sending a pointercancel for touch, prevents PE dispatches for touches until
     // all touch-points become inactive.
     bool m_inCanceledStateForPointerTypeTouch;
 
     // Note that this map keeps track of node under pointer with id=1 as well
     // which might be different than m_nodeUnderMouse in EventHandler. That one
     // keeps track of any compatibility mouse event positions but this map for
     // the pointer with id=1 is only taking care of true mouse related events.
-    HeapHashMap<int, EventTargetAttributes> m_nodeUnderPointer;
+    using NodeUnderPointerMap = HeapHashMap<int, EventTargetAttributes,
+        WTF::IntHash<int>, WTF::UnsignedWithZeroKeyHashTraits<int>>;
+    NodeUnderPointerMap m_nodeUnderPointer;
 
     PointerCapturingMap m_pointerCaptureTarget;
     PointerCapturingMap m_pendingPointerCaptureTarget;
     PointerEventFactory m_pointerEventFactory;
+

[dtapuska, 2016/04/27 17:07:04]

If there isn't a comment I don't think it needs a new line.

[Navid Zolghadr, 2016/04/28 15:13:11]

Done.

+    TouchEventManager m_touchEventManager;
+
 };
 
 } // namespace blink
 
 #endif // PointerEventManager_h