docshell/shistory/public/nsISHistory.idl
author Jim Blandy <jimb@mozilla.com>
Tue, 24 Jun 2014 22:12:07 -0700
changeset 199513 69d61e42d5dfbf4588b72449249ff3e7f2125304
parent 186739 a38d0ab6d6b844c65448f601bd7b668f5f2d7cd5
permissions -rw-r--r--
Bug 914753: Make Emacs file variable header lines correct, or at least consistent. DONTBUILD r=ehsan The -*- file variable lines -*- establish per-file settings that Emacs will pick up. This patch makes the following changes to those lines (and touches nothing else): - Never set the buffer's mode. Years ago, Emacs did not have a good JavaScript mode, so it made sense to use Java or C++ mode in .js files. However, Emacs has had js-mode for years now; it's perfectly serviceable, and is available and enabled by default in all major Emacs packagings. Selecting a mode in the -*- file variable line -*- is almost always the wrong thing to do anyway. It overrides Emacs's default choice, which is (now) reasonable; and even worse, it overrides settings the user might have made in their '.emacs' file for that file extension. It's only useful when there's something specific about that particular file that makes a particular mode appropriate. - Correctly propagate settings that establish the correct indentation level for this file: c-basic-offset and js2-basic-offset should be js-indent-level. Whatever value they're given should be preserved; different parts of our tree use different indentation styles. - We don't use tabs in Mozilla JS code. Always set indent-tabs-mode: nil. Remove tab-width: settings, at least in files that don't contain tab characters. - Remove js2-mode settings that belong in the user's .emacs file, like js2-skip-preprocessor-directives.

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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/. */

#include "nsISupports.idl"

interface nsISHEntry;
interface nsISHistoryListener;
interface nsISimpleEnumerator;
/**
 * An interface to the primary properties of the Session History
 * component. In an embedded browser environment, the nsIWebBrowser
 * object creates an instance of session history for each open window.
 * A handle to the session history object can be obtained from
 * nsIWebNavigation. In a non-embedded situation, the  owner of the
 * session history component must create a instance of it and set
 * it in the nsIWebNavigation object.
 * This interface is accessible from javascript.
 */
 

%{C++
#define NS_SHISTORY_CID \
{0x7b807041, 0xe60a, 0x4384, {0x93, 0x5f, 0xaf, 0x30, 0x61, 0xd8, 0xb8, 0x15}}

#define NS_SHISTORY_CONTRACTID "@mozilla.org/browser/shistory;1"
%}

[scriptable, uuid(7b807041-e60a-4384-935f-af3061d8b815)]
interface nsISHistory: nsISupports
{
  /**
   * A readonly property of the interface that returns 
   * the number of toplevel documents currently available
   * in session history.
   */
   readonly attribute long count;

  /**
   * A readonly property of the interface that returns 
   * the index of the current document in session history.
   */
   readonly attribute long index;

  /**
   * A readonly property of the interface that returns 
   * the index of the last document that started to load and
   * didn't finished yet. When document finishes the loading
   * value -1 is returned.
   */
   readonly attribute long requestedIndex;

  /**
   * A read/write property of the interface, used to Get/Set
   * the maximum number of toplevel documents, session history 
   * can hold for each instance. 
   */
   attribute long maxLength;

  /**
   * Called to obtain handle to the history entry at a
   * given index.
   *
   * @param index             The index value whose entry is requested.
   *                          The oldest entry is located at index == 0.
   * @param modifyIndex       A boolean flag that indicates if the current
   *                          index of session history should be modified 
   *                          to the parameter index.
   *
   * @return                  <code>NS_OK</code> history entry for 
   *                          the index is obtained successfully.
   *                          <code>NS_ERROR_FAILURE</code> Error in obtaining
   *                          history entry for the given index.
   */
   nsISHEntry getEntryAtIndex(in long index, in boolean modifyIndex);


  /**
   * Called to purge older documents from history.
   * Documents can be removed from session history for various 
   * reasons. For example to  control memory usage of the browser, to 
   * prevent users from loading documents from history, to erase evidence of
   * prior page loads etc...
   *
   * @param numEntries        The number of toplevel documents to be
   *                          purged from history. During purge operation,
   *                          the latest documents are maintained and older 
   *                          'numEntries' documents are removed from history.
   * @throws                  <code>NS_SUCCESS_LOSS_OF_INSIGNIFICANT_DATA</code> Purge was vetod.
   * @throws                  <code>NS_ERROR_FAILURE</code> numEntries is
   *                          invalid or out of bounds with the size of history.
   *                          
   */
   void PurgeHistory(in long numEntries);

  /**
   * Called to register a listener for the session history component.
   * Listeners are notified when pages are loaded or purged from history.
   * 
   * @param aListener         Listener object to be notified for all
   *                          page loads that initiate in session history.
   *
   * @note                    A listener object must implement 
   *                          nsISHistoryListener and nsSupportsWeakReference
   *
   * @see nsISHistoryListener
   * @see nsSupportsWeakReference
   */
   void addSHistoryListener(in nsISHistoryListener aListener);

  /**
   * Called to remove a listener for the session history component.
   * Listeners are notified when pages are loaded from history.
   * 
   * @param aListener         Listener object to be removed from 
   *                          session history.
   *
   * @note                    A listener object must implement 
   *                          nsISHistoryListener and nsSupportsWeakReference
   * @see nsISHistoryListener
   * @see nsSupportsWeakReference
   */ 
   void removeSHistoryListener(in nsISHistoryListener aListener);

  /**
   * Called to obtain a enumerator for all the  documents stored in 
   * session history. The enumerator object thus returned by this method
   * can be traversed using nsISimpleEnumerator. 
   *
   * @note  To access individual history entries of the enumerator, perform the
   *        following steps:
   *        1) Call nsISHistory->GetSHistoryEnumerator() to obtain handle 
   *           the nsISimpleEnumerator object.
   *        2) Use nsISimpleEnumerator->GetNext() on the object returned
   *           by step #1 to obtain handle to the next object in the list. 
   *           The object returned by this step is of type nsISupports.
   *        3) Perform a QueryInterface on the object returned by step #2 
   *           to nsISHEntry.
   *        4) Use nsISHEntry to access properties of each history entry. 
   *
   * @see nsISimpleEnumerator
   * @see nsISHEntry
   * @see QueryInterface()
   * @see do_QueryInterface()
   */
   readonly attribute nsISimpleEnumerator SHistoryEnumerator;

   void reloadCurrentEntry();

   /**
   * Called to obtain the index to a given history entry.
   *
   * @param aEntry            The entry to obtain the index of.
   *
   * @return                  <code>NS_OK</code> index for the history entry
   *                          is obtained successfully.
   *                          <code>NS_ERROR_FAILURE</code> Error in obtaining
   *                          index for the given history entry.
   */
   long getIndexOfEntry(in nsISHEntry aEntry);
};