gecko/dom/base/nsFocusManager.h

447 lines
17 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozila.org code.
*
* The Initial Developer of the Original Code is Mozilla Corporation
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsFocusManager_h___
#define nsFocusManager_h___
#include "nsIFocusManager.h"
#include "nsWeakReference.h"
#include "nsIObserver.h"
#include "nsIContent.h"
#define FOCUSMETHOD_MASK 0xF000
#define FOCUSMANAGER_CONTRACTID "@mozilla.org/focus-manager;1"
class nsIDocShellTreeItem;
class nsPIDOMWindow;
struct nsDelayedBlurOrFocusEvent;
/**
* The focus manager keeps track of where the focus is, that is, the node
* which receives key events.
*/
class nsFocusManager : public nsIFocusManager,
public nsIObserver,
public nsSupportsWeakReference
{
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();
/**
* Retrieve the single focus manager.
*/
static nsIFocusManager* GetFocusManager() { return sInstance; }
/**
* 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.
*/
static nsIContent* GetFocusedDescendant(nsPIDOMWindow* aWindow, PRBool aDeep,
nsPIDOMWindow** 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 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 nsIContent* GetRedirectedFocus(nsIContent* aContent);
protected:
nsFocusManager();
~nsFocusManager();
/**
* Ensure that the widget associated with the currently focused window is
* focused at the widget level.
*/
void EnsureCurrentWidgetFocused();
/**
* 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.
*
* 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(nsIContent* aNewContent, PRInt32 aFlags, PRBool aFocusChanged);
/**
* Returns true if aPossibleAncestor is the same as aWindow or an
* ancestor of aWindow.
*/
PRBool IsSameOrAncestor(nsPIDOMWindow* aPossibleAncestor,
nsPIDOMWindow* 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<nsPIDOMWindow> GetCommonAncestor(nsPIDOMWindow* aWindow1,
nsPIDOMWindow* 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(nsPIDOMWindow* aNewWindow);
/**
* Returns true if aWindow is visible.
*/
PRBool IsWindowVisible(nsPIDOMWindow* aWindow);
/**
* 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.
*/
nsIContent* CheckIfFocusable(nsIContent* aContent, PRUint32 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.
*/
PRBool Blur(nsPIDOMWindow* aWindowToClear,
nsPIDOMWindow* aAncestorWindowToFocus,
PRBool aIsLeavingDocument);
/**
* 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.
*/
void Focus(nsPIDOMWindow* aWindow,
nsIContent* aContent,
PRUint32 aFlags,
PRBool aIsNewDocument,
PRBool aFocusChanged,
PRBool aWindowRaised);
/**
* Fires a focus or blur event at aTarget.
*
* aType should be either NS_FOCUS_CONTENT or NS_BLUR_CONTENT. For blur
* events, aFocusMethod should normally be non-zero.
*/
void SendFocusOrBlurEvent(PRUint32 aType,
nsIPresShell* aPresShell,
nsIDocument* aDocument,
nsISupports* aTarget,
PRUint32 aFocusMethod);
/**
* Scrolls aContent into view unless the FLAG_NOSCROLL flag is set.
*/
void ScrollIntoView(nsIPresShell* aPresShell,
nsIContent* aContent,
PRUint32 aFlags);
/**
* Raises the top-level window aWindow at the widget level.
*/
void RaiseWindow(nsPIDOMWindow* 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(PRBool aMoveCaretToFocus,
PRBool 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,
PRBool 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.
*/
nsresult DetermineElementToMoveFocus(nsPIDOMWindow* aWindow,
nsIContent* aStart,
PRInt32 aType,
nsIContent** aNextContent);
/**
* 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.
*
* 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,
PRBool aForward,
PRInt32 aCurrentTabIndex,
PRBool aIgnoreTabIndex,
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(PRBool aForward,
PRInt32 aCurrentTabIndex,
nsIContent* 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.
*/
PRInt32 GetNextTabIndex(nsIContent* aParent,
PRInt32 aCurrentTabIndex,
PRBool aForward);
/**
* 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 aIsForDocNavigation is true, and aWindow is in an <iframe>.
* - if aIsForDocNavigation is false, and aWindow is a chrome shell.
* - if aCheckVisibility is true and the aWindow is not visible.
* - if aDocument is a frameset document.
*/
nsIContent* GetRootForFocus(nsPIDOMWindow* aWindow,
nsIDocument* aDocument,
PRBool aIsForDocNavigation,
PRBool aCheckVisibility);
/**
* Get the last docshell child of aItem and return it in aResult.
*/
void GetLastDocShell(nsIDocShellTreeItem* aItem,
nsIDocShellTreeItem** aResult);
/**
* Get the next docshell child of aItem and return it in aResult.
*/
void GetNextDocShell(nsIDocShellTreeItem* aItem,
nsIDocShellTreeItem** aResult);
/**
* Get the previous docshell child of aItem and return it in aResult.
*/
void GetPreviousDocShell(nsIDocShellTreeItem* aItem,
nsIDocShellTreeItem** aResult);
/**
* Get the tabbable next document from the currently focused frame if
* aForward is true, or the previously tabbable document if aForward is
* false. If this document is a chrome or frameset document, returns
* the first focusable element within this document, otherwise, returns
* the root node of the document.
*
* This method would be used for document navigation, which is typically
* invoked by pressing F6.
*/
nsIContent* GetNextTabbableDocument(PRBool aForward);
/**
* 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(nsPIDOMWindow* aWindow,
nsIContent* aStartSelection,
nsIContent* aEndSelection,
nsIContent** aFocusedContent);
// the currently active and front-most top-most window
nsCOMPtr<nsPIDOMWindow> 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.
nsCOMPtr<nsPIDOMWindow> 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.
nsCOMPtr<nsIContent> mFocusedContent;
// 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<nsPIDOMWindow> mWindowBeingLowered;
// synchronized actions cannot be interrupted with events, so queue these up
// and fire them later.
nsTArray<nsDelayedBlurOrFocusEvent> mDelayedBlurFocusEvents;
// the single focus manager
static nsIFocusManager* sInstance;
};
nsresult
NS_NewFocusManager(nsIFocusManager** aResult);
#endif