gecko-dev/layout/base/TouchCaret.h
2014-06-04 22:57:00 +02:00

245 lines
7.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 sw=2 et tw=78: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_TouchCaret_h__
#define mozilla_TouchCaret_h__
#include "nsISelectionListener.h"
#include "nsIScrollObserver.h"
#include "nsIWeakReferenceUtils.h"
#include "nsFrameSelection.h"
#include "nsITimer.h"
#include "mozilla/EventForwards.h"
#include "mozilla/TouchEvents.h"
#include "Units.h"
namespace mozilla {
/**
* The TouchCaret places a touch caret according to caret postion when the
* caret is shown.
* TouchCaret is also responsible for touch caret visibility. Touch caret
* won't be shown when timer expires or while key event causes selection change.
*/
class TouchCaret MOZ_FINAL : public nsISelectionListener
{
public:
explicit TouchCaret(nsIPresShell* aPresShell);
~TouchCaret();
NS_DECL_ISUPPORTS
NS_DECL_NSISELECTIONLISTENER
void Terminate()
{
mPresShell = nullptr;
}
/**
* Handle mouse and touch event only.
* Depends on visibility and position of touch caret, HandleEvent may consume
* that input event and return nsEventStatus_eConsumeNoDefault to the caller.
* In that case, caller should stop bubble up that input event.
*/
nsEventStatus HandleEvent(WidgetEvent* aEvent);
/**
* By calling this function, touch caret recalculate touch frame position and
* update accordingly.
*/
void UpdateTouchCaret(bool aVisible);
/**
* SetVisibility will set the visibility of the touch caret.
* SetVisibility performs an attribute-changed notification which could, in
* theory, destroy frames.
*/
void SetVisibility(bool aVisible);
/**
* GetVisibility will get the visibility of the touch caret.
*/
bool GetVisibility() const
{
return mVisible;
}
private:
// Hide default constructor.
TouchCaret() MOZ_DELETE;
/**
* Find the nsCanvasFrame which holds the touch caret.
*/
nsIFrame* GetCanvasFrame();
/**
* Retrieve the bounding rectangle of the touch caret.
*
* @returns A nsRect representing the bounding rectangle of this touch caret.
* The returned offset is relative to the canvas frame.
*/
nsRect GetTouchFrameRect();
/**
* Retrieve the bounding rectangle where the caret can be positioned.
* If we're positioning a caret in an input field, make sure the touch caret
* stays within the bounds of the field.
*
* @returns A nsRect representing the bounding rectangle of this valid area.
* The returned offset is relative to the canvas frame.
*/
nsRect GetContentBoundary();
/**
* Retrieve the center y position of the caret.
* The returned point is relative to the canvas frame.
*/
nscoord GetCaretYCenterPosition();
/**
* Set the position of the touch caret.
* Touch caret is an absolute positioned div.
*/
void SetTouchFramePos(const nsPoint& aOrigin);
void LaunchExpirationTimer();
void CancelExpirationTimer();
static void DisableTouchCaretCallback(nsITimer* aTimer, void* aPresShell);
/**
* Move the caret to movePoint which is relative to the canvas frame.
* Caret will be scrolled into view.
*
* @param movePoint tap location relative to the canvas frame.
*/
void MoveCaret(const nsPoint& movePoint);
/**
* Check if aPoint is inside the touch caret frame.
*
* @param aPoint tap location relative to the canvas frame.
*/
bool IsOnTouchCaret(const nsPoint& aPoint);
/**
* These Handle* functions comprise input alphabet of the TouchCaret
* finite-state machine triggering state transitions.
*/
nsEventStatus HandleMouseMoveEvent(WidgetMouseEvent* aEvent);
nsEventStatus HandleMouseUpEvent(WidgetMouseEvent* aEvent);
nsEventStatus HandleMouseDownEvent(WidgetMouseEvent* aEvent);
nsEventStatus HandleTouchMoveEvent(WidgetTouchEvent* aEvent);
nsEventStatus HandleTouchUpEvent(WidgetTouchEvent* aEvent);
nsEventStatus HandleTouchDownEvent(WidgetTouchEvent* aEvent);
/**
* Get the coordinates of a given touch event, relative to canvas frame.
* @param aEvent the event
* @param aIdentifier the mIdentifier of the touch which is to be converted.
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the touch are not known (e.g.,
* the mIdentifier touch is not found).
*/
nsPoint GetEventPosition(WidgetTouchEvent* aEvent, int32_t aIdentifier);
/**
* Get the coordinates of a given mouse event, relative to canvas frame.
* @param aEvent the event
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the mouse are not known.
*/
nsPoint GetEventPosition(WidgetMouseEvent* aEvent);
/**
* States of TouchCaret finite-state machine.
*/
enum TouchCaretState {
// In this state, either there is no touch/mouse event going on, or the
// first stroke does not hit the touch caret.
// Will enter TOUCHCARET_TOUCHDRAG_ACTIVE state if the first touch stroke
// hits the touch caret. Will enter TOUCHCARET_MOUSEDRAG_ACTIVE state if
// mouse (left button) down hits the touch caret.
// Allowed next state: TOUCHCARET_MOUSEDRAG_ACTIVE,
// TOUCHCARET_TOUCHDRAG_ACTIVE.
TOUCHCARET_NONE,
// The first (left button) mouse down hits on the touch caret and is
// alive. Will enter TOUCHCARET_NONE state if the left button is release.
// Allowed next states: TOUCHCARET_NONE.
TOUCHCARET_MOUSEDRAG_ACTIVE,
// The first touch start event hits on touch caret and is alive.
// Will enter TOUCHCARET_NONE state if the finger on touch caret is
// removed and there are no more fingers on the screen; will enter
// TOUCHCARET_TOUCHDRAG_INACTIVE state if the finger on touch caret is
// removed but still has fingers touching on the screen.
// Allowed next states: TOUCHCARET_NONE, TOUCHCARET_TOUCHDRAG_INACTIVE.
TOUCHCARET_TOUCHDRAG_ACTIVE,
// The first touch stroke, which hit on touch caret, is dead, but still has
// fingers touching on the screen.
// Will enter TOUCHCARET_NONE state if all the fingers are removed from the
// screen.
// Allowed next state: TOUCHCARET_NONE.
TOUCHCARET_TOUCHDRAG_INACTIVE,
};
/**
* Do actual state transition and reset substates.
*/
void SetState(TouchCaretState aState);
/**
* Current state we're dealing with.
*/
TouchCaretState mState;
/**
* Array containing all active touch IDs. When a touch happens, it gets added
* to this array, even if we choose not to handle it. When it ends, we remove
* it. We need to maintain this array in order to detect the end of the
* "multitouch" states because touch start events contain all current touches,
* but touch end events contain only those touches that have gone.
*/
nsTArray<int32_t> mTouchesId;
/**
* The mIdentifier of the touch which is on the touch caret.
*/
int32_t mActiveTouchId;
/**
* The offset between the tap location and the center of caret along y axis.
*/
nscoord mCaretCenterToDownPointOffsetY;
static int32_t TouchCaretMaxDistance()
{
return sTouchCaretMaxDistance;
}
static int32_t TouchCaretExpirationTime()
{
return sTouchCaretExpirationTime;
}
protected:
nsWeakPtr mPresShell;
// Touch caret visibility
bool mVisible;
// Touch caret timer
nsCOMPtr<nsITimer> mTouchCaretExpirationTimer;
// Preference
static int32_t sTouchCaretMaxDistance;
static int32_t sTouchCaretExpirationTime;
// The auto scroll timer's interval in miliseconds.
friend class SelectionCarets;
static const int32_t sAutoScrollTimerDelay = 30;
};
} //namespace mozilla
#endif //mozilla_TouchCaret_h__