Print Preview: Fixing behavior of event listeners.

chrome/common/print_messages.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.
 
 // IPC messages for printing.
 // Multiply-included message file, hence no include guard.
 
 #include "base/values.h"
 #include "base/shared_memory.h"
 #include "ipc/ipc_message_macros.h"
@@ skipping 32 matching lines @@
   // Cookie for the document to ensure correctness.
   IPC_STRUCT_MEMBER(int, document_cookie)
 
   // Should only print currently selected text.
   IPC_STRUCT_MEMBER(bool, selection_only)
 
   // Does the printer support alpha blending?
   IPC_STRUCT_MEMBER(bool, supports_alpha_blend)
 
   IPC_STRUCT_MEMBER(int, preview_request_id)
+  IPC_STRUCT_MEMBER(bool, is_first_request)

[Lei Zhang, 2011/08/06 00:52:57]

nit: can you comment these two struct members and mention they are only used for
print preview?

[dpapad, 2011/08/06 01:21:20]

Done.

 IPC_STRUCT_END()
 
 IPC_STRUCT_BEGIN(PrintMsg_PrintPage_Params)
   // Parameters to render the page as a printed page. It must always be the same
   // value for all the document.
   IPC_STRUCT_MEMBER(PrintMsg_Print_Params, params)
 
   // The page number is the indicator of the square that should be rendered
   // according to the layout specified in PrintMsg_Print_Params.
   IPC_STRUCT_MEMBER(int, page_number)
@@ skipping 37 matching lines @@
 IPC_STRUCT_BEGIN(PrintHostMsg_DidPreviewPage_Params)
   // A shared memory handle to metafile data for a draft document of the page.
   IPC_STRUCT_MEMBER(base::SharedMemoryHandle, metafile_data_handle)
 
   // Size of metafile data.
   IPC_STRUCT_MEMBER(uint32, data_size)
 
   // |page_number| is zero-based and can be |printing::INVALID_PAGE_INDEX| if it
   // is just a check.
   IPC_STRUCT_MEMBER(int, page_number)
+
+  // The id of the preview request.
+  IPC_STRUCT_MEMBER(int, preview_request_id)
 IPC_STRUCT_END()
 
 // Parameters to describe a rendered page.
 IPC_STRUCT_BEGIN(PrintHostMsg_DidPrintPage_Params)
   // A shared memory handle to the EMF data. This data can be quite large so a
   // memory map needs to be used.
   IPC_STRUCT_MEMBER(base::SharedMemoryHandle, metafile_data_handle)
 
   // Size of the metafile data.
   IPC_STRUCT_MEMBER(uint32, data_size)
@@ skipping 132 matching lines @@
                             base::FileDescriptor /* temp file fd */,
                             int /* fd in browser*/)
 IPC_MESSAGE_CONTROL1(PrintHostMsg_TempFileForPrintingWritten,
                      int /* fd in browser */)
 #endif
 
 // Asks the browser to do print preview.
 IPC_MESSAGE_ROUTED0(PrintHostMsg_RequestPrintPreview)
 
 // Notify the browser the number of pages in the print preview document.
-IPC_MESSAGE_ROUTED3(PrintHostMsg_DidGetPreviewPageCount,
+IPC_MESSAGE_ROUTED4(PrintHostMsg_DidGetPreviewPageCount,
                     int  /* document cookie */,
                     int  /* page count */,
-                    bool /* is modifiable */)
+                    bool /* is modifiable */,
+                    int  /* preview_request_id */)
 
 // Notify the browser a print preview page has been rendered.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_DidPreviewPage,
                     PrintHostMsg_DidPreviewPage_Params /* params */)
 
 // Sends back to the browser the complete rendered document for print preview
 // that was requested by a PrintMsg_PrintPreview message. The memory handle in
 // this message is already valid in the browser process.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_PagesReadyForPreview,
                     PrintHostMsg_DidPreviewDocument_Params /* params */)
 
 // Tell the browser printing failed.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_PrintingFailed,
                     int /* document cookie */)
 
 // Tell the browser print preview failed.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_PrintPreviewFailed,
                     int /* document cookie */)