方法1

像@Wladamir在你所链接的那个主题中说的那样，但是他没有提供示例代码，你在每个窗口中都向该命令元素添加了事件监听器。

var DOMWindows = Services.wm.getEnumerator(null);
while (DOMWindows.hasMoreElements()) {
    var aDOMWindow = DOMWindows.getNext();
    var aCommand = aDOMWindow.document.getElementById('Browser:SavePage');
    if (aCommand) {
        aCommand.addEventListener('command', function(e) {
                console.log('doing command', 'id:', e.target.id, 'e:', e);
            }, false);
    }
}

e对象上的变量查看器：

确保跟踪未来打开的窗口。

方法2

或者这里是对Browser:SavePage调用的命令的调查，我们可以在这里找到要跟踪的内容：

似乎它调用savePage函数：

function saveDocument(aDocument, aSkipPrompt)
{
  if (!aDocument)
    throw "Must have a document when calling saveDocument";

  // We want to use cached data because the document is currently visible.
  var ifreq =
    aDocument.defaultView
             .QueryInterface(Components.interfaces.nsIInterfaceRequestor);

  var contentDisposition = null;
  try {
    contentDisposition =
      ifreq.getInterface(Components.interfaces.nsIDOMWindowUtils)
           .getDocumentMetadata("content-disposition");
  } catch (ex) {
    // Failure to get a content-disposition is ok
  }

  var cacheKey = null;
  try {
    cacheKey =
      ifreq.getInterface(Components.interfaces.nsIWebNavigation)
           .QueryInterface(Components.interfaces.nsIWebPageDescriptor);
  } catch (ex) {
    // We might not find it in the cache.  Oh, well.
  }

  internalSave(aDocument.location.href, aDocument, null, contentDisposition,
               aDocument.contentType, false, null, null,
               aDocument.referrer ? makeURI(aDocument.referrer) : null,
               aDocument, aSkipPrompt, cacheKey);
}

它看起来像是internalSave：

function internalSave(aURL, aDocument, aDefaultFileName, aContentDisposition,
                      aContentType, aShouldBypassCache, aFilePickerTitleKey,
                      aChosenData, aReferrer, aInitiatingDocument, aSkipPrompt,
                      aCacheKey)
{
  if (aSkipPrompt == undefined)
    aSkipPrompt = false;

  if (aCacheKey == undefined)
    aCacheKey = null;

  // Note: aDocument == null when this code is used by save-link-as...
  var saveMode = GetSaveModeForContentType(aContentType, aDocument);

  var file, sourceURI, saveAsType;
  // Find the URI object for aURL and the FileName/Extension to use when saving.
  // FileName/Extension will be ignored if aChosenData supplied.
  if (aChosenData) {
    file = aChosenData.file;
    sourceURI = aChosenData.uri;
    saveAsType = kSaveAsType_Complete;

    continueSave();
  } else {
    var charset = null;
    if (aDocument)
      charset = aDocument.characterSet;
    else if (aReferrer)
      charset = aReferrer.originCharset;
    var fileInfo = new FileInfo(aDefaultFileName);
    initFileInfo(fileInfo, aURL, charset, aDocument,
                 aContentType, aContentDisposition);
    sourceURI = fileInfo.uri;

    var fpParams = {
      fpTitleKey: aFilePickerTitleKey,
      fileInfo: fileInfo,
      contentType: aContentType,
      saveMode: saveMode,
      saveAsType: kSaveAsType_Complete,
      file: file
    };

    // Find a URI to use for determining last-downloaded-to directory
    let relatedURI = aReferrer || sourceURI;

    promiseTargetFile(fpParams, aSkipPrompt, relatedURI).then(aDialogAccepted => {
      if (!aDialogAccepted)
        return;

      saveAsType = fpParams.saveAsType;
      file = fpParams.file;

      continueSave();
    }).then(null, Components.utils.reportError);
  }

  function continueSave() {
    // XXX We depend on the following holding true in appendFiltersForContentType():
    // If we should save as a complete page, the saveAsType is kSaveAsType_Complete.
    // If we should save as text, the saveAsType is kSaveAsType_Text.
    var useSaveDocument = aDocument &&
                          (((saveMode & SAVEMODE_COMPLETE_DOM) && (saveAsType == kSaveAsType_Complete)) ||
                           ((saveMode & SAVEMODE_COMPLETE_TEXT) && (saveAsType == kSaveAsType_Text)));
    // If we're saving a document, and are saving either in complete mode or
    // as converted text, pass the document to the web browser persist component.
    // If we're just saving the HTML (second option in the list), send only the URI.
    var persistArgs = {
      sourceURI         : sourceURI,
      sourceReferrer    : aReferrer,
      sourceDocument    : useSaveDocument ? aDocument : null,
      targetContentType : (saveAsType == kSaveAsType_Text) ? "text/plain" : null,
      targetFile        : file,
      sourceCacheKey    : aCacheKey,
      sourcePostData    : aDocument ? getPostData(aDocument) : null,
      bypassCache       : aShouldBypassCache,
      initiatingWindow  : aInitiatingDocument.defaultView
    };

    // Start the actual save process
    internalPersist(persistArgs);
  }
}

调用internalPersist：

function internalPersist(persistArgs)
{
  var persist = makeWebBrowserPersist();

  // Calculate persist flags.
  const nsIWBP = Components.interfaces.nsIWebBrowserPersist;
  const flags = nsIWBP.PERSIST_FLAGS_REPLACE_EXISTING_FILES |
                nsIWBP.PERSIST_FLAGS_FORCE_ALLOW_COOKIES;
  if (persistArgs.bypassCache)
    persist.persistFlags = flags | nsIWBP.PERSIST_FLAGS_BYPASS_CACHE;
  else
    persist.persistFlags = flags | nsIWBP.PERSIST_FLAGS_FROM_CACHE;

  // Leave it to WebBrowserPersist to discover the encoding type (or lack thereof):
  persist.persistFlags |= nsIWBP.PERSIST_FLAGS_AUTODETECT_APPLY_CONVERSION;

  // Find the URI associated with the target file
  var targetFileURL = makeFileURI(persistArgs.targetFile);

  var isPrivate = PrivateBrowsingUtils.isWindowPrivate(persistArgs.initiatingWindow);

  // Create download and initiate it (below)
  var tr = Components.classes["@mozilla.org/transfer;1"].createInstance(Components.interfaces.nsITransfer);
  tr.init(persistArgs.sourceURI,
          targetFileURL, "", null, null, null, persist, isPrivate);
  persist.progressListener = new DownloadListener(window, tr);

  if (persistArgs.sourceDocument) {
    // Saving a Document, not a URI:
    var filesFolder = null;
    if (persistArgs.targetContentType != "text/plain") {
      // Create the local directory into which to save associated files.
      filesFolder = persistArgs.targetFile.clone();

      var nameWithoutExtension = getFileBaseName(filesFolder.leafName);
      var filesFolderLeafName =
        ContentAreaUtils.stringBundle
                        .formatStringFromName("filesFolder", [nameWithoutExtension], 1);

      filesFolder.leafName = filesFolderLeafName;
    }

    var encodingFlags = 0;
    if (persistArgs.targetContentType == "text/plain") {
      encodingFlags |= nsIWBP.ENCODE_FLAGS_FORMATTED;
      encodingFlags |= nsIWBP.ENCODE_FLAGS_ABSOLUTE_LINKS;
      encodingFlags |= nsIWBP.ENCODE_FLAGS_NOFRAMES_CONTENT;
    }
    else {
      encodingFlags |= nsIWBP.ENCODE_FLAGS_ENCODE_BASIC_ENTITIES;
    }

    const kWrapColumn = 80;
    persist.saveDocument(persistArgs.sourceDocument, targetFileURL, filesFolder,
                         persistArgs.targetContentType, encodingFlags, kWrapColumn);
  } else {
    let privacyContext = persistArgs.initiatingWindow
                                    .QueryInterface(Components.interfaces.nsIInterfaceRequestor)
                                    .getInterface(Components.interfaces.nsIWebNavigation)
                                    .QueryInterface(Components.interfaces.nsILoadContext);
    persist.saveURI(persistArgs.sourceURI,
                    persistArgs.sourceCacheKey, persistArgs.sourceReferrer, persistArgs.sourcePostData, null,
                    targetFileURL, privacyContext);
  }
}

所以你可以从那里挑选一些东西，但我不会看到任何简单的东西，但是必须要有东西。

Firefox插件sdk订阅已保存的页面事件

1 个答案:

方法1

方法2