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

chrome/common/print_messages.h

Index: chrome/common/print_messages.h
===================================================================
--- chrome/common/print_messages.h	(revision 97484)
+++ chrome/common/print_messages.h	(working copy)
@@ -49,10 +49,15 @@
   // 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.
@@ -220,16 +225,6 @@
 // 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)
@@ -300,6 +295,13 @@
 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.
@@ -313,3 +315,7 @@
 // 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 */)