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

chrome/renderer/print_web_view_helper.cc

Index: chrome/renderer/print_web_view_helper.cc
diff --git a/chrome/renderer/print_web_view_helper.cc b/chrome/renderer/print_web_view_helper.cc
index 5ca14e6ec35946995cad714b7eae8e6bb7c5a55b..7a0fb3d355f5f75415bc0c34ab2951e55a8368ca 100644
--- a/chrome/renderer/print_web_view_helper.cc
+++ b/chrome/renderer/print_web_view_helper.cc
@@ -139,7 +139,9 @@ bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
   return handled;
 }
 
-void PrintWebViewHelper::OnPrintForPrintPreview() {
+void PrintWebViewHelper::OnPrintForPrintPreview(
+    const DictionaryValue& job_settings) {
+#if defined(OS_MACOSX)
   if (!render_view()->webview())
     return;
   WebFrame* main_frame = render_view()->webview()->mainFrame();
@@ -155,7 +157,11 @@ void PrintWebViewHelper::OnPrintForPrintPreview() {
     return;
   }
 
-  PrintNode(&element, false, false);
+  InitPrintSettings(element.document().frame(), &element,

[Lei Zhang, 2011/03/03 00:22:44]

What happens when InitPrintSettings() or UpdatePrintSettings() fail?

[kmadhusu, 2011/03/04 19:39:02]

Fixed.

+                    PrintWebViewHelper::DEFAULT);
+  UpdatePrintSettings(job_settings);
+  PrintForPrintPreview(element.document().frame(), &element);
+#endif
 }
 
 void PrintWebViewHelper::OnPrint(bool is_preview) {
@@ -197,6 +203,23 @@ void PrintWebViewHelper::OnPrintNodeUnderContextMenu() {
   PrintNode(&context_menu_node, false, false);
 }
 
+void PrintWebViewHelper::PrintForPrintPreview(WebKit::WebFrame* frame,
+                                              WebNode* node) {
+  // If still not finished with earlier print request simply ignore.
+  if (print_web_view_)
+    return;
+
+  // Initialize print params with current print settings.
+  if (!InitPrintSettings(frame, node, PrintWebViewHelper::CURRENT)) {

[Lei Zhang, 2011/03/03 00:22:44]

Didn't we just call InitPrintSettings() and UpdatePrintSettings(). Shouldn't
|print_pages_params_| be up to date? Why do we have to fetch the settings again?

[kmadhusu, 2011/03/04 19:39:02]

Removed this function. Calling RenderPagesForPrint() directly from
OnPrintForPrintPreview(). 

+    NOTREACHED();
+    DidFinishPrinting(true); // Release all printing resources.
+    return;  // Failed to init print page settings.
+  }
+
+  // Render Pages for printing.
+  RenderPagesForPrint(frame, node);
+}
+
 void PrintWebViewHelper::Print(WebKit::WebFrame* frame,
                                WebNode* node,
                                bool script_initiated,
@@ -233,7 +256,7 @@ void PrintWebViewHelper::Print(WebKit::WebFrame* frame,
   is_preview_ = is_preview;
 
   // Initialize print settings.
-  if (!InitPrintSettings(frame, node))
+  if (!InitPrintSettings(frame, node, PrintWebViewHelper::DEFAULT))
     return;  // Failed to init print page settings.
 
   int expected_pages_count = 0;
@@ -489,9 +512,10 @@ void PrintWebViewHelper::UpdatePrintableSizeInPrintParameters(
 }
 
 bool PrintWebViewHelper::InitPrintSettings(WebFrame* frame,
-                                           WebNode* node) {
+                                           WebNode* node,
+                                           GetSettingsParam setting_type) {
   ViewMsg_PrintPages_Params settings;
-  if (GetDefaultPrintSettings(frame, node, &settings.params)) {
+  if (GetPrintSettings(frame, node, setting_type, &settings.params)) {
     print_pages_params_.reset(new ViewMsg_PrintPages_Params(settings));
     print_pages_params_->pages.clear();
     return true;
@@ -499,12 +523,33 @@ bool PrintWebViewHelper::InitPrintSettings(WebFrame* frame,
   return false;
 }
 
-bool PrintWebViewHelper::GetDefaultPrintSettings(
-    WebFrame* frame,
-    WebNode* node,
-    ViewMsg_Print_Params* params) {
-  if (!render_view()->Send(new ViewHostMsg_GetDefaultPrintSettings(
-          render_view()->routing_id(), params))) {
+bool PrintWebViewHelper::UpdatePrintSettings(
+    const DictionaryValue& job_settings) {
+  ViewMsg_PrintPages_Params settings;
+  IPC::SyncMessage* msg = new ViewHostMsg_UpdatePrintSettings(
+      render_view()->routing_id(),
+      (*print_pages_params_).params.document_cookie,
+      job_settings, &settings.params);
+  if (!render_view()->Send(msg)) {
+    NOTREACHED();
+    return false;
+  }
+  print_pages_params_.reset(new ViewMsg_PrintPages_Params(settings));
+  return true;
+}
+
+bool PrintWebViewHelper::GetPrintSettings(WebFrame* frame, WebNode* node,
+    GetSettingsParam setting_type, ViewMsg_Print_Params* params) {
+  IPC::SyncMessage* msg = NULL;
+  if (setting_type == CURRENT) {
+    msg = new ViewHostMsg_GetCurrentPrintSettings(render_view()->routing_id(),
+              (*print_pages_params_).params.document_cookie,
+              params);
+  } else {
+    msg = new ViewHostMsg_GetDefaultPrintSettings(render_view()->routing_id(),
+                                                  params);
+  }
+  if (!render_view()->Send(msg)) {
     NOTREACHED();
     return false;
   }