gecko-dev/dom/events/ContentEventHandler.h

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6.8 KiB
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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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_ContentEventHandler_h_
#define mozilla_ContentEventHandler_h_
#include "mozilla/EventForwards.h"
#include "nsCOMPtr.h"
#include "nsISelection.h"
#include "nsRange.h"
class nsPresContext;
struct nsRect;
namespace mozilla {
enum LineBreakType
{
LINE_BREAK_TYPE_NATIVE,
LINE_BREAK_TYPE_XP
};
/*
* Query Content Event Handler
* ContentEventHandler is a helper class for EventStateManager.
* The platforms request some content informations, e.g., the selected text,
* the offset of the selected text and the text for specified range.
* This class answers to NS_QUERY_* events from actual contents.
*/
class MOZ_STACK_CLASS ContentEventHandler
{
public:
explicit ContentEventHandler(nsPresContext* aPresContext);
// NS_QUERY_SELECTED_TEXT event handler
nsresult OnQuerySelectedText(WidgetQueryContentEvent* aEvent);
// NS_QUERY_TEXT_CONTENT event handler
nsresult OnQueryTextContent(WidgetQueryContentEvent* aEvent);
// NS_QUERY_CARET_RECT event handler
nsresult OnQueryCaretRect(WidgetQueryContentEvent* aEvent);
// NS_QUERY_TEXT_RECT event handler
nsresult OnQueryTextRect(WidgetQueryContentEvent* aEvent);
// NS_QUERY_EDITOR_RECT event handler
nsresult OnQueryEditorRect(WidgetQueryContentEvent* aEvent);
// NS_QUERY_CONTENT_STATE event handler
nsresult OnQueryContentState(WidgetQueryContentEvent* aEvent);
// NS_QUERY_SELECTION_AS_TRANSFERABLE event handler
nsresult OnQuerySelectionAsTransferable(WidgetQueryContentEvent* aEvent);
// NS_QUERY_CHARACTER_AT_POINT event handler
nsresult OnQueryCharacterAtPoint(WidgetQueryContentEvent* aEvent);
// NS_QUERY_DOM_WIDGET_HITTEST event handler
nsresult OnQueryDOMWidgetHittest(WidgetQueryContentEvent* aEvent);
// NS_SELECTION_* event
nsresult OnSelectionEvent(WidgetSelectionEvent* aEvent);
protected:
nsPresContext* mPresContext;
nsCOMPtr<nsIPresShell> mPresShell;
nsCOMPtr<nsISelection> mSelection;
nsRefPtr<nsRange> mFirstSelectedRange;
nsCOMPtr<nsIContent> mRootContent;
nsresult Init(WidgetQueryContentEvent* aEvent);
nsresult Init(WidgetSelectionEvent* aEvent);
nsresult InitBasic();
nsresult InitCommon();
public:
// FlatText means the text that is generated from DOM tree. The BR elements
// are replaced to native linefeeds. Other elements are ignored.
// Get the offset in FlatText of the range. (also used by IMEContentObserver)
static nsresult GetFlatTextOffsetOfRange(nsIContent* aRootContent,
nsINode* aNode,
int32_t aNodeOffset,
uint32_t* aOffset,
LineBreakType aLineBreakType);
static nsresult GetFlatTextOffsetOfRange(nsIContent* aRootContent,
nsRange* aRange,
uint32_t* aOffset,
LineBreakType aLineBreakType);
// Computes the native text length between aStartOffset and aEndOffset of
// aContent. Currently, this method supports only text node or br element
// for aContent.
static uint32_t GetNativeTextLength(nsIContent* aContent,
uint32_t aStartOffset,
uint32_t aEndOffset);
// Get the native text length of a content node excluding any children
static uint32_t GetNativeTextLength(nsIContent* aContent,
uint32_t aMaxLength = UINT32_MAX);
// Get the text length of a given range of a content node in
// the given line break type.
static uint32_t GetTextLengthInRange(nsIContent* aContent,
uint32_t aXPStartOffset,
uint32_t aXPEndOffset,
LineBreakType aLineBreakType);
protected:
static uint32_t GetTextLength(nsIContent* aContent,
LineBreakType aLineBreakType,
uint32_t aMaxLength = UINT32_MAX);
static LineBreakType GetLineBreakType(WidgetQueryContentEvent* aEvent);
static LineBreakType GetLineBreakType(WidgetSelectionEvent* aEvent);
static LineBreakType GetLineBreakType(bool aUseNativeLineBreak);
// Returns focused content (including its descendant documents).
nsIContent* GetFocusedContent();
// Returns true if the content is a plugin host.
bool IsPlugin(nsIContent* aContent);
// QueryContentRect() sets the rect of aContent's frame(s) to aEvent.
nsresult QueryContentRect(nsIContent* aContent,
WidgetQueryContentEvent* aEvent);
// Make the DOM range from the offset of FlatText and the text length.
// If aExpandToClusterBoundaries is true, the start offset and the end one are
// expanded to nearest cluster boundaries.
nsresult SetRangeFromFlatTextOffset(nsRange* aRange,
uint32_t aOffset,
uint32_t aLength,
LineBreakType aLineBreakType,
bool aExpandToClusterBoundaries,
uint32_t* aNewOffset = nullptr);
// Find the first textframe for the range, and get the start offset in
// the frame.
nsresult GetStartFrameAndOffset(nsRange* aRange,
nsIFrame** aFrame,
int32_t* aOffsetInFrame);
// Convert the frame relative offset to the root view relative offset.
nsresult ConvertToRootViewRelativeOffset(nsIFrame* aFrame,
nsRect& aRect);
// Expand aXPOffset to the nearest offset in cluster boundary. aForward is
// true, it is expanded to forward.
nsresult ExpandToClusterBoundary(nsIContent* aContent, bool aForward,
uint32_t* aXPOffset);
typedef nsTArray<mozilla::FontRange> FontRangeArray;
static void AppendFontRanges(FontRangeArray& aFontRanges,
nsIContent* aContent,
int32_t aBaseOffset,
int32_t aXPStartOffset,
int32_t aXPEndOffset,
LineBreakType aLineBreakType);
static nsresult GenerateFlatFontRanges(nsRange* aRange,
FontRangeArray& aFontRanges,
uint32_t& aLength,
LineBreakType aLineBreakType);
};
} // namespace mozilla
#endif // mozilla_ContentEventHandler_h_