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

printing/printing_context.h

-// Copyright (c) 2010 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 PRINTING_PRINTING_CONTEXT_H_
 #define PRINTING_PRINTING_CONTEXT_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/string16.h"
 #include "printing/print_settings.h"
 #include "ui/gfx/native_widget_types.h"
 
+class DictionaryValue;
+
 namespace printing {
 
 // An abstraction of a printer context, implemented by objects that describe the
 // user selected printing context. This includes the OS-dependent UI to ask the
 // user about the print settings. Concrete implementations directly talk to the
 // printer and manage the document and page breaks.
 class PrintingContext {
  public:
   // Tri-state result for user behavior-dependent functions.
   enum Result {
@@ skipping 17 matching lines @@
                                   bool has_selection,
                                   PrintSettingsCallback* callback) = 0;
 
   // Selects the user's default printer and format. Updates the context with the
   // default device settings.
   virtual Result UseDefaultSettings() = 0;
 
   // Initializes with predefined settings.
   virtual Result InitWithSettings(const PrintSettings& settings) = 0;
 
+  // Update print settings.
+  virtual Result UpdatePrintSettings(const DictionaryValue* job_settings,

[Lei Zhang, 2011/02/18 05:21:42]

Why do you have |job_settings| that's unused in all the PrintingContext
implementations?

[kmadhusu, 2011/02/21 01:30:26]

Removed that argument. 

+                                     const PageRanges& ranges) = 0;
+
   // Does platform specific setup of the printer before the printing. Signal the
   // printer that a document is about to be spooled.
   // Warning: This function enters a message loop. That may cause side effects
   // like IPC message processing! Some printers have side-effects on this call
   // like virtual printers that ask the user for the path of the saved document;
   // for example a PDF printer.
   virtual Result NewDocument(const string16& document_name) = 0;
 
   // Starts a new page.
   virtual Result NewPage() = 0;
@@ skipping 51 matching lines @@
 
   // The application locale.
   std::string app_locale_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintingContext);
 };
 
 }  // namespace printing
 
 #endif  // PRINTING_PRINTING_CONTEXT_H_