Print Preview: Hook up the print button to initiate printing without displaying a print dialog.

chrome/browser/printing/print_job_worker.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PRINTING_PRINT_JOB_WORKER_H__
 #define CHROME_BROWSER_PRINTING_PRINT_JOB_WORKER_H__
 #pragma once
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
@@ skipping 24 matching lines @@
   void SetNewOwner(PrintJobWorkerOwner* new_owner);
 
   // Initializes the print settings. If |ask_user_for_settings| is true, a
   // Print... dialog box will be shown to ask the user his preference.
   void GetSettings(bool ask_user_for_settings,
                    gfx::NativeView parent_view,
                    int document_page_count,
                    bool has_selection,
                    bool use_overlays);
 
+  // Set the new print settings. |new_settings| is a json string.
+  void SetSettings(const std::string& new_settings);
+
   // Starts the printing loop. Every pages are printed as soon as the data is
   // available. Makes sure the new_document is the right one.
   void StartPrinting(PrintedDocument* new_document);
 
   // Updates the printed document.
   void OnDocumentChanged(PrintedDocument* new_document);
 
   // Unqueues waiting pages. Called when PrintJob receives a
   // NOTIFY_PRINTED_DOCUMENT_UPDATED notification. It's time to look again if
   // the next page can be printed.
@@ skipping 30 matching lines @@
   // but sticks with this for consistency.
   void GetSettingsWithUI(gfx::NativeView parent_view,
                          int document_page_count,
                          bool has_selection);
 
   // The callback used by PrintingContext::GetSettingsWithUI() to notify this
   // object that the print settings are set.  This is needed in order to bounce
   // back into the IO thread for GetSettingsDone().
   void GetSettingsWithUIDone(PrintingContext::Result result);
 
+  // Called on a UI thread to update the print settings.

[James Hawkins, 2011/02/16 22:58:21]

s/a/the/

[kmadhusu, 2011/02/17 19:20:31]

Done.

+  void UpdatePrintSettings(const std::string& new_settings);
+
   // Reports settings back to owner_.
   void GetSettingsDone(PrintingContext::Result result);
 
   // Use the default settings. When using GTK+ or Mac, this can still end up
   // displaying a dialog. So this needs to happen from the UI thread on these
   // systems.
   void UseDefaultSettings();
 
   // Information about the printer setting.
   scoped_ptr<PrintingContext> printing_context_;
@@ skipping 15 matching lines @@
 
 template <>
 struct RunnableMethodTraits<printing::PrintJobWorker> {
   void RetainCallee(printing::PrintJobWorker* obj);
   void ReleaseCallee(printing::PrintJobWorker* obj);
  private:
   scoped_refptr<printing::PrintJobWorkerOwner> owner_;
 };
 
 #endif  // CHROME_BROWSER_PRINTING_PRINT_JOB_WORKER_H__