Print Preview: Go from event driven print preview back to print preview with sync messages. The s...

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 31 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)
 
-  // The id of the preview request, used only for print preview.
+  // *** Parameters below are used only for print preview. ***
+
+  // The print preview ui associated with this request.
+  IPC_STRUCT_MEMBER(std::string, preview_ui_addr)

[Lei Zhang, 2011/08/20 03:25:52]

This is going to cause a crash when we do a memset() on the struct.

+
+  // The id of the preview request.
   IPC_STRUCT_MEMBER(int, preview_request_id)
 
-  // True if this is the first preview request, used only for print preview.
+  // True if this is the first preview request.
   IPC_STRUCT_MEMBER(bool, is_first_request)
 
   // Specifies if the header and footer should be rendered.
   IPC_STRUCT_MEMBER(bool, display_header_footer)
 
   // Date string to be printed as header if requested by the user.
   IPC_STRUCT_MEMBER(string16, date)
 
   // Title string to be printed as header if requested by the user.
   IPC_STRUCT_MEMBER(string16, title)
@@ skipping 147 matching lines @@
 // called multiple times as the user updates settings.
 IPC_MESSAGE_ROUTED1(PrintMsg_PrintPreview,
                     DictionaryValue /* settings */)
 
 // Like PrintMsg_PrintPages, but using the print preview document's frame/node.
 IPC_MESSAGE_ROUTED0(PrintMsg_PrintForSystemDialog)
 
 // Tells a renderer to stop blocking script initiated printing.
 IPC_MESSAGE_ROUTED0(PrintMsg_ResetScriptedPrintCount)
 
-// Tells a renderer to continue generating the print preview.
-// Use |requested_preview_page_index| to request a specific preview page data.
-// |requested_preview_page_index| is 1-based or |printing::INVALID_PAGE_INDEX|
-// to render the next page.
-IPC_MESSAGE_ROUTED1(PrintMsg_ContinuePreview,
-                    int /* requested_preview_page_index */)
-
-// Tells a renderer to abort the print preview and reset all state.
-IPC_MESSAGE_ROUTED0(PrintMsg_AbortPreview)
-
 // Messages sent from the renderer to the browser.
 
 #if defined(OS_WIN)
 // Duplicates a shared memory handle from the renderer to the browser. Then
 // the renderer can flush the handle.
 IPC_SYNC_MESSAGE_ROUTED1_1(PrintHostMsg_DuplicateSection,
                            base::SharedMemoryHandle /* renderer handle */,
                            base::SharedMemoryHandle /* browser handle */)
 #endif
 
@@ skipping 50 matching lines @@
 IPC_MESSAGE_ROUTED0(PrintHostMsg_RequestPrintPreview)
 
 // Notify the browser the number of pages in the print preview document.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_DidGetPreviewPageCount,
                     PrintHostMsg_DidGetPreviewPageCount_Params /* params */)
 
 // Notify the browser a print preview page has been rendered.
 IPC_MESSAGE_ROUTED1(PrintHostMsg_DidPreviewPage,
                     PrintHostMsg_DidPreviewPage_Params /* params */)
 
+// Asks the browser whether the print preview has been cancelled,
+// and if not, what page to render next.
+IPC_SYNC_MESSAGE_ROUTED2_1(PrintHostMsg_CheckForCancel,
+                           std::string /* print preview ui address */,
+                           int /* request id */,
+                           bool /* print preview cancelled */)
+
 // 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 */)
+
+// Tell the browser print preview was cancelled.
+IPC_MESSAGE_ROUTED1(PrintHostMsg_PrintPreviewCancelled,
+                    int /* document cookie */)