Added Header and Footer support using Skia

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 "base/memory/scoped_ptr.h"
 #include "base/shared_memory.h"
 #include "base/time.h"
+#include "base/utf_string_conversions.h"
+#include "base/values.h"
 #include "content/renderer/render_view_observer.h"
 #include "content/renderer/render_view_observer_tracker.h"
 #include "printing/metafile.h"
+#include "skia/ext/vector_canvas.h"
+#include "third_party/skia/include/core/SkPaint.h"
+#include "third_party/skia/include/core/SkRefCnt.h"
+#include "third_party/skia/include/core/SkScalar.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrameClient.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebViewClient.h"
 #include "ui/gfx/size.h"
 
 class DictionaryValue;
 struct PrintMsg_Print_Params;
 struct PrintMsg_PrintPage_Params;
 struct PrintMsg_PrintPages_Params;
 
 // Class that calls the Begin and End print functions on the frame and changes
@@ skipping 75 matching lines @@
 
   // Message handlers ---------------------------------------------------------
 
   // Print the document.
   void OnPrintPages();
 
   // Initiate print preview.
   void OnInitiatePrintPreview();
 
   // Generate a print preview using |settings|.
-  void OnPrintPreview(const DictionaryValue& settings);
+  // |header_footer_info| contains the necessary strings generated by the
+  // browser process to be printed as headers and footers if requested by the
+  // user.
+  void OnPrintPreview(const DictionaryValue& settings,
+      const DictionaryValue& header_footer_info);

[kmadhusu, 2011/07/13 18:47:53]

nit: Fix indentation.

[Aayush Kumar, 2011/07/13 21:52:16]

Done.

 
   // Print / preview the node under the context menu.
   void OnPrintNodeUnderContextMenu();
 
   // Print the pages for print preview. Do not display the native print dialog
   // for user settings. |job_settings| has new print job settings values.
   void OnPrintForPrintPreview(const DictionaryValue& job_settings);
 
   void OnPrintingDone(bool success);
 
@@ skipping 37 matching lines @@
   // It will implicitly revert the document to display CSS media type.
   bool PrintPages(const PrintMsg_PrintPages_Params& params,
                   WebKit::WebFrame* frame,
                   WebKit::WebNode* node);
 
   // Prints the page listed in |params|.
 #if defined(USE_X11)
   void PrintPageInternal(const PrintMsg_PrintPage_Params& params,
                          const gfx::Size& canvas_size,
                          WebKit::WebFrame* frame,
-                         printing::Metafile* metafile);
+                         printing::Metafile* metafile,
+                         bool is_preview,
+                         int total_pages);
 #else
   void PrintPageInternal(const PrintMsg_PrintPage_Params& params,
                          const gfx::Size& canvas_size,
                          WebKit::WebFrame* frame);
 #endif
 
   // Render the frame for printing.
   bool RenderPagesForPrint(WebKit::WebFrame* frame, WebKit::WebNode* node);
 
   // Render the frame for preview.
@@ skipping 97 matching lines @@
   base::Time last_cancelled_script_print_;
   int user_cancelled_scripted_print_count_;
 
   // Let the browser process know of a printing failure. Only set to false when
   // the failure came from the browser in the first place.
   bool notify_browser_of_print_failure_;
 
   int preview_page_count_;
   scoped_ptr<PrintMsg_PrintPages_Params> old_print_pages_params_;
 
+  // Contains strings generated by the browser process to be printed as headers
+  // and footers if requested by the user.
+  const DictionaryValue* header_footer_info_;
+
+  // Specifies the horizontal alignment of the Headers and Footers.
+  enum HorizontalHeaderFooterPosition {

[kmadhusu, 2011/07/13 18:47:53]

Move these enums to print_job_constants.h &.cc and the new functions to an
unnamed namespace. 

+    LEFT,
+    CENTER,
+    RIGHT
+  };
+
+  // Specifies the vertical alignment of the Headers and Footers.
+  enum VerticalHeaderFooterPosition {
+    TOP,
+    BOTTOM
+  };
+
+  // Gets the x-coordinate from where we want to start printing the current text
+  // depending on the alignment (LEFT, RIGHT, CENTER).
+  SkScalar GetHorizontalCoordinate(
+    string16 text,
+    SkPaint paint,
+    HorizontalHeaderFooterPosition pos,
+    SkScalar margin_left_in_points,
+    SkScalar margin_right_in_points,
+    SkScalar content_width_in_points);
+
+  // Gets the y-coordinate from where we want to start printing based on if we
+  // are printing the Header or the Footer (TOP or BOTTOM).
+  SkScalar GetVerticalCoordinate(
+    SkPaint paint,
+    VerticalHeaderFooterPosition pos,
+    SkScalar margin_left_in_points,
+    SkScalar margin_right_in_points,
+    SkScalar content_height_in_points);
+
+  // Interstice or gap between different Header and Footer components.
+  // Hardcoded to 0.25cm = 1/10" = 7.2 points
+  const SkScalar header_footer_interstice;
+
+  // Given a text, the positions and the paint object, this method calculates
+  // the coordinates and prints the text at those co-ordinates.
+  void PrintHeaderFooterText(
+      string16 text,
+      SkPaint paint,
+      const SkRefPtr<skia::VectorCanvas>& canvas,
+      SkScalar margin_left_in_points,

[Lei Zhang, 2011/07/12 22:04:50]

Consider using some additional data structures. When your method has 12 methods,
it's getting pretty ugly.

[Aayush Kumar, 2011/07/13 21:52:16]

Now private variables in PrintWebViewHelper class
On 2011/07/12 22:04:50, Lei Zhang wrote:

+      SkScalar margin_right_in_points,
+      SkScalar content_width_in_points,
+      SkScalar margin_top_in_points,
+      SkScalar margin_bottom_in_points,
+      SkScalar content_height_in_points,
+      HorizontalHeaderFooterPosition hor_pos,
+      VerticalHeaderFooterPosition ver_pos);
+
   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 };
 
 #endif  // CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_