src/third_party/WebKit/Source/core/page/FocusController.h

   1 /*
   2  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef FocusController_h
  27 #define FocusController_h
  28
  29 #include "core/page/FocusType.h"
  30 #include "platform/geometry/LayoutRect.h"
  31 #include "platform/heap/Handle.h"
  32 #include "wtf/Forward.h"
  33 #include "wtf/Noncopyable.h"
  34 #include "wtf/RefPtr.h"
  35
  36 namespace blink {
  37
  38 struct FocusCandidate;
  39 class Element;
  40 class Frame;
  41 class HTMLFrameOwnerElement;
  42 class HTMLShadowElement;
  43 class Node;
  44 class Page;
  45 class TreeScope;
  46
  47 class FocusNavigationScope {
  48     STACK_ALLOCATED();
  49 public:
  50     Node* rootNode() const;
  51     Element* owner() const;
  52     static FocusNavigationScope focusNavigationScopeOf(Node&);
  53     static FocusNavigationScope ownedByNonFocusableFocusScopeOwner(Node&);
  54     static FocusNavigationScope ownedByShadowHost(Node&);
  55     static FocusNavigationScope ownedByShadowInsertionPoint(HTMLShadowElement&);
  56     static FocusNavigationScope ownedByIFrame(HTMLFrameOwnerElement&);
  57
  58 private:
  59     explicit FocusNavigationScope(TreeScope*);
  60     RawPtrWillBeMember<TreeScope> m_rootTreeScope;
  61 };
  62
  63 class FocusController final : public NoBaseWillBeGarbageCollectedFinalized<FocusController> {
  64     WTF_MAKE_NONCOPYABLE(FocusController); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
  65 public:
  66     static PassOwnPtrWillBeRawPtr<FocusController> create(Page*);
  67
  68     void setFocusedFrame(PassRefPtrWillBeRawPtr<Frame>);
  69     void focusDocumentView(PassRefPtrWillBeRawPtr<Frame>);
  70     Frame* focusedFrame() const { return m_focusedFrame.get(); }
  71     Frame* focusedOrMainFrame() const;
  72
  73     bool setInitialFocus(FocusType);
  74     bool advanceFocus(FocusType type) { return advanceFocus(type, false); }
  75
  76     bool setFocusedElement(Element*, PassRefPtrWillBeRawPtr<Frame>, FocusType = FocusTypeNone);
  77
  78     void setActive(bool);
  79     bool isActive() const { return m_isActive; }
  80
  81     void setFocused(bool);
  82     bool isFocused() const { return m_isFocused; }
  83
  84     void trace(Visitor*);
  85
  86 private:
  87     explicit FocusController(Page*);
  88
  89     bool advanceFocus(FocusType, bool initialFocus);
  90     bool advanceFocusDirectionally(FocusType);
  91     bool advanceFocusInDocumentOrder(FocusType, bool initialFocus);
  92
  93     Node* findFocusableNodeAcrossFocusScope(FocusType, FocusNavigationScope startScope, Node* start);
  94     Node* findFocusableNodeRecursively(FocusType, FocusNavigationScope, Node* start);
  95     Node* findFocusableNodeDecendingDownIntoFrameDocument(FocusType, Node*);
  96
  97     // Searches through the given tree scope, starting from start node, for the next/previous selectable element that comes after/before start node.
  98     // The order followed is as specified in section 17.11.1 of the HTML4 spec, which is elements with tab indexes
  99     // first (from lowest to highest), and then elements without tab indexes (in document order).
 100     //
 101     // @param start The node from which to start searching. The node after this will be focused. May be null.
 102     //
 103     // @return The focus node that comes after/before start node.
 104     //
 105     // See http://www.w3.org/TR/html4/interact/forms.html#h-17.11.1
 106     inline Node* findFocusableNode(FocusType, FocusNavigationScope, Node* start);
 107
 108     Node* nextFocusableNode(FocusNavigationScope, Node* start);
 109     Node* previousFocusableNode(FocusNavigationScope, Node* start);
 110
 111     Node* findNodeWithExactTabIndex(Node* start, int tabIndex, FocusType);
 112
 113     bool advanceFocusDirectionallyInContainer(Node* container, const LayoutRect& startingRect, FocusType);
 114     void findFocusCandidateInContainer(Node& container, const LayoutRect& startingRect, FocusType, FocusCandidate& closest);
 115
 116     RawPtrWillBeMember<Page> m_page;
 117     RefPtrWillBeMember<Frame> m_focusedFrame;
 118     bool m_isActive;
 119     bool m_isFocused;
 120     bool m_isChangingFocusedFrame;
 121 };
 122
 123 } // namespace blink
 124
 125 #endif // FocusController_h