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

chrome/renderer/print_web_view_helper.h

 // 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_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #define CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 71 matching lines @@
   explicit PrintWebViewHelper(RenderView* render_view);
   virtual ~PrintWebViewHelper();
 
   // Prints |frame|.
   void PrintFrame(WebKit::WebFrame* frame,
                   bool script_initiated,
                   bool is_preview);
 
   // Message handlers.  Public for testing.
   void OnPrintingDone(int document_cookie, bool success);
-  void OnPrintForPrintPreview();
+  void OnPrintForPrintPreview(const std::string& job_settings);
   void OnPrintPages();
   void OnPrintPreview();
   void OnPrintNodeUnderContextMenu();
 
  protected:
   bool CopyAndPrint(WebKit::WebFrame* web_frame);
 
   // Prints the page listed in |params|.
 #if defined(USE_X11)
   void PrintPage(const ViewMsg_PrintPage_Params& params,
@@ skipping 10 matching lines @@
   // Prints all the pages listed in |params|.
   // It will implicitly revert the document to display CSS media type.
   void PrintPages(const ViewMsg_PrintPages_Params& params,
                   WebKit::WebFrame* frame,
                   WebKit::WebNode* node);
 
   // WebKit::WebViewClient override:
   virtual void didStopLoading();
 
  private:
+  enum GetSettingsParam {
+    DEFAULT,

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

Do you intend to have more types in this enum? If not, why not just use a bool?

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

Just for readability and better understanding of the code, I went for enum. I am
not planning to add more types to this enum. 

+    CURRENT,
+  };
+
   static void GetPageSizeAndMarginsInPoints(
       WebKit::WebFrame* frame,
       int page_index,
       const ViewMsg_Print_Params& default_params,
       double* content_width_in_points,
       double* content_height_in_points,
       double* margin_top_in_points,
       double* margin_right_in_points,
       double* margin_bottom_in_points,
       double* margin_left_in_points);
 
   // RenderViewObserver implementation.
   virtual bool OnMessageReceived(const IPC::Message& message);
 
   // Common method for OnPrintPages() and OnPrintPreview().
   void OnPrint(bool is_preview);
 
   void PrintNode(WebKit::WebNode* node,
                  bool script_initiated,
-                 bool is_preview);
+                 bool is_preview,
+                 bool is_print_for_print_preview);
 
   // Notification when printing is done - signal teardown
   void DidFinishPrinting(bool success);
 
+  // Print the pages for print preview. Do not display the native print dialog
+  // for user settings.  Use the current print settings set by the user in
+  // preview tab.
+  void PrintForPrintPreview(WebKit::WebFrame* frame, WebKit::WebNode* node);
+
   void Print(WebKit::WebFrame* frame,
              WebKit::WebNode* node,
              bool script_initiated,
              bool is_preview);
 
   void UpdatePrintableSizeInPrintParameters(WebKit::WebFrame* frame,
                                             WebKit::WebNode* node,
                                             ViewMsg_Print_Params* params);
 
   // Initialize print page settings with default settings.
   bool InitPrintSettings(WebKit::WebFrame* frame,
-                         WebKit::WebNode* node);
+                         WebKit::WebNode* node,
+                         GetSettingsParam setting_type);
 
-  // Get the default printer settings.
-  bool GetDefaultPrintSettings(WebKit::WebFrame* frame,
-                               WebKit::WebNode* node,
-                               ViewMsg_Print_Params* params);
+  // Update the current print settings with new |job_settings|. |job_settings|
+  // is a json string which contains print job details such as printer name,
+  // number of copies, page range, etc.
+  bool UpdatePrintSettings(const std::string& job_settings);
+
+  // Get the print settings. |setting_type| determines whether we need to get
+  // current settings or default settings.
+  bool GetPrintSettings(WebKit::WebFrame* frame,
+                        WebKit::WebNode* node,
+                        GetSettingsParam setting_type,
+                        ViewMsg_Print_Params* params);
 
   // Get final print settings from the user.
   // Return false if the user cancels or on error.
   bool GetPrintSettingsFromUser(WebKit::WebFrame* frame,
                                 int expected_pages_count,
                                 bool use_browser_overlays);
 
   // Render the frame for printing.
   void RenderPagesForPrint(WebKit::WebFrame* frame,
                            WebKit::WebNode* node);
@@ skipping 25 matching lines @@
   scoped_ptr<ViewMsg_PrintPages_Params> print_pages_params_;
   base::Time last_cancelled_script_print_;
   int user_cancelled_scripted_print_count_;
   bool is_preview_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 };
 
 #endif  // CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_