gecko-dev/dom/base/nsFocusManager.h

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 nsFocusManager_h___
#define nsFocusManager_h___
#include "nsCycleCollectionParticipant.h"
#include "nsIContent.h"
#include "nsIDocument.h"
#include "nsIFocusManager.h"
#include "nsIObserver.h"
#include "nsIWidget.h"
#include "nsWeakReference.h"
#include "mozilla/Attributes.h"
#include "mozilla/RefPtr.h"
#define FOCUSMETHOD_MASK 0xF000
#define FOCUSMETHODANDRING_MASK 0xF0F000
#define FOCUSMANAGER_CONTRACTID "@mozilla.org/focus-manager;1"
class nsIContent;
class nsIDocShellTreeItem;
class nsPIDOMWindowOuter;
namespace mozilla {
namespace dom {
class Element;
class TabParent;
}
}
struct nsDelayedBlurOrFocusEvent;
/**
* The focus manager keeps track of where the focus is, that is, the node
* which receives key events.
*/
class nsFocusManager final : public nsIFocusManager,
public nsIObserver,
public nsSupportsWeakReference
{
typedef mozilla::widget::InputContextAction InputContextAction;
public:
NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsFocusManager, nsIFocusManager)
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_NSIOBSERVER
NS_DECL_NSIFOCUSMANAGER
// called to initialize and stop the focus manager at startup and shutdown
static nsresult Init();
static void Shutdown();
void PrefChanged(const char* aPref);
/**
* Retrieve the single focus manager.
*/
static nsFocusManager* GetFocusManager() { return sInstance; }
/**
* A faster version of nsIFocusManager::GetFocusedElement, returning a
* raw Element pointer (instead of having AddRef-ed Element
* pointer filled in to an out-parameter).
*/
mozilla::dom::Element* GetFocusedElement() { return mFocusedElement; }
/**
* Returns true if aContent currently has focus.
*/
bool IsFocused(nsIContent* aContent);
/**
* Returns true if test mode is enabled.
*/
bool IsTestMode();
/**
* Return a focused window. Version of nsIFocusManager::GetFocusedWindow.
*/
nsPIDOMWindowOuter* GetFocusedWindow() const { return mFocusedWindow; }
/**
* Return an active window. Version of nsIFocusManager::GetActiveWindow.
*/
nsPIDOMWindowOuter* GetActiveWindow() const { return mActiveWindow; }
/**
* Called when content has been removed.
*/
nsresult ContentRemoved(nsIDocument* aDocument, nsIContent* aContent);
/**
* Called when mouse button event handling is started and finished.
*/
already_AddRefed<nsIDocument>
SetMouseButtonHandlingDocument(nsIDocument* aDocument)
{
nsCOMPtr<nsIDocument> handlingDocument = mMouseButtonEventHandlingDocument;
mMouseButtonEventHandlingDocument = aDocument;
return handlingDocument.forget();
}
void NeedsFlushBeforeEventHandling(mozilla::dom::Element* aElement)
{
if (mFocusedElement == aElement) {
mEventHandlingNeedsFlush = true;
}
}
bool CanSkipFocus(nsIContent* aContent);
void FlushBeforeEventHandlingIfNeeded(nsIContent* aContent)
{
if (mEventHandlingNeedsFlush) {
nsCOMPtr<nsIDocument> doc = aContent->GetComposedDoc();
if (doc) {
mEventHandlingNeedsFlush = false;
doc->FlushPendingNotifications(mozilla::FlushType::Layout);
}
}
}
/**
* Update the caret with current mode (whether in caret browsing mode or not).
*/
void UpdateCaretForCaretBrowsingMode();
/**
* Returns the content node that would be focused if aWindow was in an
* active window. This will traverse down the frame hierarchy, starting at
* the given window aWindow. Sets aFocusedWindow to the window with the
* document containing aFocusedContent. If no element is focused,
* aFocusedWindow may be still be set -- this means that the document is
* focused but no element within it is focused.
*
* aWindow and aFocusedWindow must both be non-null.
*/
enum SearchRange
{
// Return focused content in aWindow. So, aFocusedWindow is always aWindow.
eOnlyCurrentWindow,
// Return focused content in aWindow or one of all sub windows.
eIncludeAllDescendants,
// Return focused content in aWindow or one of visible sub windows.
eIncludeVisibleDescendants,
};
static mozilla::dom::Element*
GetFocusedDescendant(nsPIDOMWindowOuter* aWindow,
SearchRange aSearchRange,
nsPIDOMWindowOuter** aFocusedWindow);
/**
* Returns the content node that focus will be redirected to if aContent was
* focused. This is used for the special case of certain XUL elements such
* as textboxes or input number which redirect focus to an anonymous child.
*
* aContent must be non-null.
*
* XXXndeakin this should be removed eventually but I want to do that as
* followup work.
*/
static mozilla::dom::Element* GetRedirectedFocus(nsIContent* aContent);
/**
* Returns an InputContextAction cause for aFlags.
*/
static InputContextAction::Cause GetFocusMoveActionCause(uint32_t aFlags);
static bool sMouseFocusesFormControl;
static void MarkUncollectableForCCGeneration(uint32_t aGeneration);
protected:
nsFocusManager();
~nsFocusManager();
/**
* Ensure that the widget associated with the currently focused window is
* focused at the widget level.
*/
void EnsureCurrentWidgetFocused();
/**
* Activate or deactivate the window and send the activate/deactivate events.
*/
void ActivateOrDeactivate(nsPIDOMWindowOuter* aWindow, bool aActive);
/**
* Blur whatever is currently focused and focus aNewContent. aFlags is a
* bitmask of the flags defined in nsIFocusManager. If aFocusChanged is
* true, then the focus has actually shifted and the caret position will be
* updated to the new focus, aNewContent will be scrolled into view (unless
* a flag disables this) and the focus method for the window will be updated.
* If aAdjustWidget is false, don't change the widget focus state.
*
* All actual focus changes must use this method to do so. (as opposed
* to those that update the focus in an inactive window for instance).
*/
void SetFocusInner(mozilla::dom::Element* aNewContent, int32_t aFlags,
bool aFocusChanged, bool aAdjustWidget);
/**
* Returns true if aPossibleAncestor is the same as aWindow or an
* ancestor of aWindow.
*/
bool IsSameOrAncestor(nsPIDOMWindowOuter* aPossibleAncestor,
nsPIDOMWindowOuter* aWindow);
/**
* Returns the window that is the lowest common ancestor of both aWindow1
* and aWindow2, or null if they share no common ancestor.
*/
already_AddRefed<nsPIDOMWindowOuter>
GetCommonAncestor(nsPIDOMWindowOuter* aWindow1, nsPIDOMWindowOuter* aWindow2);
/**
* When aNewWindow is focused, adjust the ancestors of aNewWindow so that they
* also have their corresponding frames focused. Thus, one can start at
* the active top-level window and navigate down the currently focused
* elements for each frame in the tree to get to aNewWindow.
*/
void AdjustWindowFocus(nsPIDOMWindowOuter* aNewWindow, bool aCheckPermission);
/**
* Returns true if aWindow is visible.
*/
bool IsWindowVisible(nsPIDOMWindowOuter* aWindow);
/**
* Returns true if aContent is a root element and not focusable.
* I.e., even if aContent is editable root element, this returns true when
* the document is in designMode.
*
* @param aContent must not be null and must be in a document.
*/
bool IsNonFocusableRoot(nsIContent* aContent);
/**
* Checks and returns aContent if it may be focused, another content node if
* the focus should be retargeted at another node, or null if the node
* cannot be focused. aFlags are the flags passed to SetFocus and similar
* methods.
*
* An element is focusable if it is in a document, the document isn't in
* print preview mode and the element has an nsIFrame where the
* CheckIfFocusable method returns true. For <area> elements, there is no
* frame, so only the IsFocusable method on the content node must be
* true.
*/
mozilla::dom::Element* CheckIfFocusable(mozilla::dom::Element* aContent,
uint32_t aFlags);
/**
* Blurs the currently focused element. Returns false if another element was
* focused as a result. This would mean that the caller should not proceed
* with a pending call to Focus. Normally, true would be returned.
*
* The currently focused element within aWindowToClear will be cleared.
* aWindowToClear may be null, which means that no window is cleared. This
* will be the case, for example, when lowering a window, as we want to fire
* a blur, but not actually change what element would be focused, so that
* the same element will be focused again when the window is raised.
*
* aAncestorWindowToFocus should be set to the common ancestor of the window
* that is being blurred and the window that is going to focused, when
* switching focus to a sibling window.
*
* aIsLeavingDocument should be set to true if the document/window is being
* blurred as well. Document/window blur events will be fired. It should be
* false if an element is the same document is about to be focused.
*
* If aAdjustWidget is false, don't change the widget focus state.
*/
// MOZ_CAN_RUN_SCRIPT_BOUNDARY for now, until we annotate callers.
MOZ_CAN_RUN_SCRIPT_BOUNDARY
bool Blur(nsPIDOMWindowOuter* aWindowToClear,
nsPIDOMWindowOuter* aAncestorWindowToFocus,
bool aIsLeavingDocument,
bool aAdjustWidget,
nsIContent* aContentToFocus = nullptr);
/**
* Focus an element in the active window and child frame.
*
* aWindow is the window containing the element aContent to focus.
*
* aFlags is the flags passed to the various focus methods in
* nsIFocusManager.
*
* aIsNewDocument should be true if a new document is being focused.
* Document/window focus events will be fired.
*
* aFocusChanged should be true if a new content node is being focused, so
* the focused content will be scrolled into view and the caret position
* will be updated. If false is passed, then a window is simply being
* refocused, for instance, due to a window being raised, or a tab is being
* switched to.
*
* If aFocusChanged is true, then the focus has moved to a new location.
* Otherwise, the focus is just being updated because the window was
* raised.
*
* aWindowRaised should be true if the window is being raised. In this case,
* command updaters will not be called.
*
* If aAdjustWidget is false, don't change the widget focus state.
*/
void Focus(nsPIDOMWindowOuter* aWindow,
mozilla::dom::Element* aContent,
uint32_t aFlags,
bool aIsNewDocument,
bool aFocusChanged,
bool aWindowRaised,
bool aAdjustWidget,
nsIContent* aContentLostFocus = nullptr);
/**
* Send a focus or blur event at aTarget. It may be added to the delayed
* event queue if the document is suppressing events.
*
* aEventMessage should be either eFocus or eBlur.
* For blur events, aFocusMethod should normally be non-zero.
*
* aWindowRaised should only be true if called from WindowRaised.
*/
void SendFocusOrBlurEvent(mozilla::EventMessage aEventMessage,
nsIPresShell* aPresShell,
nsIDocument* aDocument,
nsISupports* aTarget,
uint32_t aFocusMethod,
bool aWindowRaised,
bool aIsRefocus = false,
mozilla::dom::EventTarget* aRelatedTarget = nullptr);
/**
* Fire a focus or blur event at aTarget.
*
* aEventMessage should be either eFocus or eBlur.
* For blur events, aFocusMethod should normally be non-zero.
*
* aWindowRaised should only be true if called from WindowRaised.
*/
void FireFocusOrBlurEvent(mozilla::EventMessage aEventMessage,
nsIPresShell* aPresShell,
nsISupports* aTarget,
bool aWindowRaised,
bool aIsRefocus = false,
mozilla::dom::EventTarget* aRelatedTarget = nullptr);
/**
* Fire a focusin or focusout event
*
* aEventMessage should be either eFocusIn or eFocusOut.
*
* aTarget is the content the event will fire on (the object that gained
* focus for focusin, the object blurred for focusout).
*
* aCurrentFocusedWindow is the window focused before the focus/blur event
* was fired.
*
* aCurrentFocusedContent is the content focused before the focus/blur event
* was fired.
*
* aRelatedTarget is the content related to the event (the object
* losing focus for focusin, the object getting focus for focusout).
*/
void FireFocusInOrOutEvent(mozilla::EventMessage aEventMessage,
nsIPresShell* aPresShell,
nsISupports* aTarget,
nsPIDOMWindowOuter* aCurrentFocusedWindow,
nsIContent* aCurrentFocusedContent,
mozilla::dom::EventTarget* aRelatedTarget = nullptr);
/**
* Scrolls aContent into view unless the FLAG_NOSCROLL flag is set.
*/
void ScrollIntoView(nsIPresShell* aPresShell,
nsIContent* aContent,
uint32_t aFlags);
/**
* Raises the top-level window aWindow at the widget level.
*/
void RaiseWindow(nsPIDOMWindowOuter* aWindow);
/**
* Updates the caret positon and visibility to match the focus.
*
* aMoveCaretToFocus should be true to move the caret to aContent.
*
* aUpdateVisibility should be true to update whether the caret is
* visible or not.
*/
void UpdateCaret(bool aMoveCaretToFocus,
bool aUpdateVisibility,
nsIContent* aContent);
/**
* Helper method to move the caret to the focused element aContent.
*/
void MoveCaretToFocus(nsIPresShell* aPresShell, nsIContent* aContent);
/**
* Makes the caret visible or not, depending on aVisible.
*/
nsresult SetCaretVisible(nsIPresShell* aPresShell,
bool aVisible,
nsIContent* aContent);
// the remaining functions are used for tab key and document-navigation
/**
* Retrieves the start and end points of the current selection for
* aDocument and stores them in aStartContent and aEndContent.
*/
nsresult GetSelectionLocation(nsIDocument* aDocument,
nsIPresShell* aPresShell,
nsIContent **aStartContent,
nsIContent **aEndContent);
/**
* Helper function for MoveFocus which determines the next element
* to move the focus to and returns it in aNextContent.
*
* aWindow is the window to adjust the focus within, and aStart is
* the element to start navigation from. For tab key navigation,
* this should be the currently focused element.
*
* aType is the type passed to MoveFocus. If aNoParentTraversal is set,
* navigation is not done to parent documents and iteration returns to the
* beginning (or end) of the starting document.
*/
nsresult DetermineElementToMoveFocus(nsPIDOMWindowOuter* aWindow,
nsIContent* aStart,
int32_t aType, bool aNoParentTraversal,
nsIContent** aNextContent);
/**
* Returns scope owner of aContent.
* A scope owner is either a document root, shadow host, or slot.
*/
nsIContent* FindOwner(nsIContent* aContent);
/**
* Returns true if aContent is a shadow host or slot
*/
bool IsHostOrSlot(nsIContent* aContent);
/**
* Host and Slot elements need to be handled as if they had tabindex 0 even
* when they don't have the attribute. This is a helper method to get the right
* value for focus navigation.
* If aIsFocusable is passed, it is set to true if the element itself is
* focusable.
*/
int32_t HostOrSlotTabIndexValue(nsIContent* aContent,
bool* aIsFocusable = nullptr);
/**
* Retrieve the next tabbable element in scope owned by aOwner, using
* focusability and tabindex to determine the tab order.
*
* aOwner is the owner of scope to search in.
*
* aStartContent is the starting point for this call of this method.
*
* aOriginalStartContent is the initial starting point for sequential
* navigation.
*
* aForward should be true for forward navigation or false for backward
* navigation.
*
* aCurrentTabIndex is the current tabindex.
*
* aIgnoreTabIndex to ignore the current tabindex and find the element
* irrespective or the tab index.
*
* aForDocumentNavigation informs whether we're navigating only through
* documents.
*
* aSkipOwner to skip owner while searching. The flag is set when caller is
* |GetNextTabbableContent| in order to let caller handle owner.
*
* NOTE:
* Consider the method searches downwards in flattened subtree
* rooted at aOwner.
*/
nsIContent* GetNextTabbableContentInScope(nsIContent* aOwner,
nsIContent* aStartContent,
nsIContent* aOriginalStartContent,
bool aForward,
int32_t aCurrentTabIndex,
bool aIgnoreTabIndex,
bool aForDocumentNavigation,
bool aSkipOwner);
/**
* Retrieve the next tabbable element in scope including aStartContent
* and the scope's ancestor scopes, using focusability and tabindex to
* determine the tab order.
*
* aStartContent an in/out paremeter. It as input is the starting point
* for this call of this method; as output it is the shadow host in
* light DOM if the next tabbable element is not found in shadow DOM,
* in order to continue searching in light DOM.
*
* aOriginalStartContent is the initial starting point for sequential
* navigation.
*
* aForward should be true for forward navigation or false for backward
* navigation.
*
* aCurrentTabIndex returns tab index of shadow host in light DOM if the
* next tabbable element is not found in shadow DOM, in order to continue
* searching in light DOM.
*
* aIgnoreTabIndex to ignore the current tabindex and find the element
* irrespective or the tab index.
*
* aForDocumentNavigation informs whether we're navigating only through
* documents.
*
* NOTE:
* Consider the method searches upwards in all shadow host- or slot-rooted
* flattened subtrees that contains aStartContent as non-root, except
* the flattened subtree rooted at shadow host in light DOM.
*/
nsIContent* GetNextTabbableContentInAncestorScopes(nsIContent** aStartContent,
nsIContent* aOriginalStartContent,
bool aForward,
int32_t* aCurrentTabIndex,
bool aIgnoreTabIndex,
bool aForDocumentNavigation);
/**
* Retrieve the next tabbable element within a document, using focusability
* and tabindex to determine the tab order. The element is returned in
* aResultContent.
*
* aRootContent is the root node -- nodes above this will not be examined.
* Typically this will be the root node of a document, but could also be
* a popup node.
*
* aOriginalStartContent is the content which was originally the starting
* node, in the case of recursive or looping calls.
*
* aStartContent is the starting point for this call of this method.
* If aStartContent doesn't have visual representation, the next content
* object, which does have a primary frame, will be used as a start.
* If that content object is focusable, the method may return it.
*
* aForward should be true for forward navigation or false for backward
* navigation.
*
* aCurrentTabIndex is the current tabindex.
*
* aIgnoreTabIndex to ignore the current tabindex and find the element
* irrespective or the tab index. This will be true when a selection is
* active, since we just want to focus the next element in tree order
* from where the selection is. Similarly, if the starting element isn't
* focusable, since it doesn't really have a defined tab index.
*/
nsresult GetNextTabbableContent(nsIPresShell* aPresShell,
nsIContent* aRootContent,
nsIContent* aOriginalStartContent,
nsIContent* aStartContent,
bool aForward,
int32_t aCurrentTabIndex,
bool aIgnoreTabIndex,
bool aForDocumentNavigation,
nsIContent** aResultContent);
/**
* Get the next tabbable image map area and returns it.
*
* aForward should be true for forward navigation or false for backward
* navigation.
*
* aCurrentTabIndex is the current tabindex.
*
* aImageContent is the image.
*
* aStartContent is the current image map area.
*/
nsIContent* GetNextTabbableMapArea(bool aForward,
int32_t aCurrentTabIndex,
mozilla::dom::Element* aImageContent,
nsIContent* aStartContent);
/**
* Return the next valid tabindex value after aCurrentTabIndex, if aForward
* is true, or the previous tabindex value if aForward is false. aParent is
* the node from which to start looking for tab indicies.
*/
int32_t GetNextTabIndex(nsIContent* aParent,
int32_t aCurrentTabIndex,
bool aForward);
/**
* Focus the first focusable content within the document with a root node of
* aRootContent. For content documents, this will be aRootContent itself, but
* for chrome documents, this will locate the next focusable content.
*/
nsresult FocusFirst(mozilla::dom::Element* aRootContent, nsIContent** aNextContent);
/**
* Retrieves and returns the root node from aDocument to be focused. Will
* return null if the root node cannot be focused. There are several reasons
* for this:
*
* - if aForDocumentNavigation is false and aWindow is a chrome shell.
* - if aCheckVisibility is true and the aWindow is not visible.
* - if aDocument is a frameset document.
*/
mozilla::dom::Element* GetRootForFocus(nsPIDOMWindowOuter* aWindow,
nsIDocument* aDocument,
bool aForDocumentNavigation,
bool aCheckVisibility);
/**
* Retrieves and returns the root node as with GetRootForFocus but only if
* aContent is a frame with a valid child document.
*/
mozilla::dom::Element* GetRootForChildDocument(nsIContent* aContent);
/**
* Retreives a focusable element within the current selection of aWindow.
* Currently, this only detects links.
*
* This is used when MoveFocus is called with a type of MOVEFOCUS_CARET,
* which is used, for example, to focus links as the caret is moved over
* them.
*/
void GetFocusInSelection(nsPIDOMWindowOuter* aWindow,
nsIContent* aStartSelection,
nsIContent* aEndSelection,
nsIContent** aFocusedContent);
private:
// Notify that the focus state of aContent has changed. Note that
// we need to pass in whether the window should show a focus ring
// before the SetFocusedNode call on it happened when losing focus
// and after the SetFocusedNode call when gaining focus, which is
// why that information needs to be an explicit argument instead of
// just passing in the window and asking it whether it should show
// focus rings: in the losing focus case that information could be
// wrong..
static void NotifyFocusStateChange(nsIContent* aContent,
nsIContent* aContentToFocus,
bool aWindowShouldShowFocusRing,
bool aGettingFocus);
void SetFocusedWindowInternal(nsPIDOMWindowOuter* aWindow);
bool TryDocumentNavigation(nsIContent* aCurrentContent,
bool* aCheckSubDocument,
nsIContent** aResultContent);
bool TryToMoveFocusToSubDocument(nsIContent* aCurrentContent,
nsIContent* aOriginalStartContent,
bool aForward,
bool aForDocumentNavigation,
nsIContent** aResultContent);
// the currently active and front-most top-most window
nsCOMPtr<nsPIDOMWindowOuter> mActiveWindow;
// the child or top-level window that is currently focused. This window will
// either be the same window as mActiveWindow or a descendant of it.
// Except during shutdown use SetFocusedWindowInternal to set mFocusedWindow!
nsCOMPtr<nsPIDOMWindowOuter> mFocusedWindow;
// the currently focused content, which is always inside mFocusedWindow. This
// is a cached copy of the mFocusedWindow's current content. This may be null
// if no content is focused.
RefPtr<mozilla::dom::Element> mFocusedElement;
// these fields store a content node temporarily while it is being focused
// or blurred to ensure that a recursive call doesn't refire the same event.
// They will always be cleared afterwards.
nsCOMPtr<nsIContent> mFirstBlurEvent;
nsCOMPtr<nsIContent> mFirstFocusEvent;
// keep track of a window while it is being lowered
nsCOMPtr<nsPIDOMWindowOuter> mWindowBeingLowered;
// synchronized actions cannot be interrupted with events, so queue these up
// and fire them later.
nsTArray<nsDelayedBlurOrFocusEvent> mDelayedBlurFocusEvents;
// A document which is handling a mouse button event.
// When a mouse down event process is finished, ESM sets focus to the target
// content if it's not consumed. Therefore, while DOM event handlers are
// handling mouse down events or preceding mosue down event is consumed but
// handling mouse up events, they should be able to steal focus from any
// elements even if focus is in chrome content. So, if this isn't nullptr
// and the caller can access the document node, the caller should succeed in
// moving focus.
nsCOMPtr<nsIDocument> mMouseButtonEventHandlingDocument;
// If set to true, layout of the document of the event target should be
// flushed before handling focus depending events.
bool mEventHandlingNeedsFlush;
static bool sTestMode;
// the single focus manager
static nsFocusManager* sInstance;
};
nsresult
NS_NewFocusManager(nsIFocusManager** aResult);
#endif