michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_layers_ActiveElementManager_h
michael@0: #define mozilla_layers_ActiveElementManager_h
michael@0: 
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsISupportsImpl.h"
michael@0: 
michael@0: class inIDOMUtils;
michael@0: class nsIDOMEventTarget;
michael@0: class nsIDOMElement;
michael@0: class CancelableTask;
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace layers {
michael@0: 
michael@0: /**
michael@0:  * Manages setting and clearing the ':active' CSS pseudostate in the presence
michael@0:  * of touch input.
michael@0:  */
michael@0: class ActiveElementManager {
michael@0: public:
michael@0:   NS_INLINE_DECL_REFCOUNTING(ActiveElementManager)
michael@0: 
michael@0:   ActiveElementManager();
michael@0:   ~ActiveElementManager();
michael@0: 
michael@0:   /**
michael@0:    * Specify the target of a touch. Typically this should be called right
michael@0:    * before HandleTouchStart(), but we give callers the flexibility to specify
michael@0:    * the target later if they don't know it at the time they call
michael@0:    * HandleTouchStart().
michael@0:    * |aTarget| may be nullptr.
michael@0:    */
michael@0:   void SetTargetElement(nsIDOMEventTarget* aTarget);
michael@0:   /**
michael@0:    * Handle a touch-start event.
michael@0:    * @param aCanBePan whether the touch can be a pan
michael@0:    */
michael@0:   void HandleTouchStart(bool aCanBePan);
michael@0:   /**
michael@0:    * Handle the start of panning.
michael@0:    */
michael@0:   void HandlePanStart();
michael@0:   /**
michael@0:    * Handle a touch-end or touch-cancel event.
michael@0:    * @param aWasClick whether the touch was a click
michael@0:    */
michael@0:   void HandleTouchEnd(bool aWasClick);
michael@0: private:
michael@0:   nsCOMPtr<inIDOMUtils> mDomUtils;
michael@0:   /**
michael@0:    * The target of the first touch point in the current touch block.
michael@0:    */
michael@0:   nsCOMPtr<nsIDOMElement> mTarget;
michael@0:   /**
michael@0:    * Whether the current touch block can be a pan. Set in HandleTouchStart().
michael@0:    */
michael@0:   bool mCanBePan;
michael@0:   /**
michael@0:    * Whether mCanBePan has been set for the current touch block.
michael@0:    * We need to keep track of this to allow HandleTouchStart() and
michael@0:    * SetTargetElement() to be called in either order.
michael@0:    */
michael@0:   bool mCanBePanSet;
michael@0:   /**
michael@0:    * A task for calling SetActive() after a timeout.
michael@0:    */
michael@0:   CancelableTask* mSetActiveTask;
michael@0: 
michael@0:   // Helpers
michael@0:   void TriggerElementActivation();
michael@0:   void SetActive(nsIDOMElement* aTarget);
michael@0:   void ResetActive();
michael@0:   void SetActiveTask(nsIDOMElement* aTarget);
michael@0:   void CancelTask();
michael@0: };
michael@0: 
michael@0: }
michael@0: }
michael@0: 
michael@0: #endif /* mozilla_layers_ActiveElementManager_h */