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

chrome/browser/printing/printer_query.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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_PRINTER_QUERY_H_
 #define CHROME_BROWSER_PRINTING_PRINTER_QUERY_H_
 #pragma once
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/printing/print_job_worker_owner.h"
 #include "ui/gfx/native_widget_types.h"
 
 class CancelableTask;
+class DictionaryValue;
 class MessageLoop;
 
 namespace base {
 class Thread;
 }
 
 namespace printing {
 
 class PrintJobWorker;
 
@@ skipping 20 matching lines @@
   // times to reinitialize the settings. |parent_view| parameter's window will
   // be the owner of the print setting dialog box. It is unused when
   // |ask_for_user_settings| is DEFAULTS.
   void GetSettings(GetSettingsAskParam ask_user_for_settings,
                    gfx::NativeView parent_view,
                    int expected_page_count,
                    bool has_selection,
                    bool use_overlays,
                    CancelableTask* callback);
 
+  // Updates the current settings with |new_settings| dictionary values.
+  void SetSettings(const DictionaryValue& new_settings,
+                   CancelableTask* callback);
+
   // Stops the worker thread since the client is done with this object.
   void StopWorker();
 
   // Returns true if a GetSettings() call is pending completion.
   bool is_callback_pending() const;
 
   PrintingContext::Result last_status() const { return last_status_; }
 
   // Returns if a worker thread is still associated to this instance.
   bool is_valid() const;
 
  private:
   virtual ~PrinterQuery();
 
+  // Lazy create the worker thread. There is one worker thread per print job.
+  // Returns true, if worker thread exists or has been created.
+  bool StartWorker(CancelableTask* callback);
+
   // Main message loop reference. Used to send notifications in the right
   // thread.
   MessageLoop* const io_message_loop_;
 
   // All the UI is done in a worker thread because many Win32 print functions
   // are blocking and enters a message loop without your consent. There is one
   // worker thread per print job.
   scoped_ptr<PrintJobWorker> worker_;
 
   // Cache of the print context settings for access in the UI thread.
@@ skipping 10 matching lines @@
 
   // Task waiting to be executed.
   scoped_ptr<CancelableTask> callback_;
 
   DISALLOW_COPY_AND_ASSIGN(PrinterQuery);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_PRINTER_QUERY_H_