new callback bridging Mozilla and embedding window creation. bug 67368 r=hyatt,jst

xpfe/bootstrap/nsWindowCreator.cpp

@@ -0,0 +1,104 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 2001 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ */
+
+/* There are several ways to open a new window in Mozilla: directly, using
+   nsAppShellService; indirectly, using the Open method on an extant
+   window, the OpenWindow method on the nsWindowWatcher service, and this
+   WindowCreator. I think that's all of them, for petessake.  But
+   the conditions under which each should be used are definite, if
+   not clear, and there is no overlap.
+
+   Basically, you should never use nsAppShellService. That's the basic
+   method that all others boil down to, and it creates partially initialized
+   windows. Trust the other means of opening windows to use nsAppShellService
+   and then finish the new window's initialization. nsAppShellService is
+   also strictly a Mozilla-only service; it's unavailable (or should be)
+   to embedding apps. So it's not merely inadvisable but also illegal
+   for any code that may execute in an embedding context to use that service.
+
+   Unless you're writing window opening code yourself, you want to use
+   the Open method on an extant window, or lacking one of those, the
+   OpenWindow method on the nsWindowWatcher service. (The former calls
+   through to the latter.) Both methods are equally at home in Mozilla
+   and embedding contexts. They differentiate between which kind of window
+   to open in different ways, depending on whether there is an extant
+   window.
+
+   Lacking an extant window, it's this object, the nsWindowCreator,
+   that allows new window creation and properly distinguishes between
+   Mozilla and embedding contexts. This source file contains the
+   Mozilla version, which calls through to nsAppShellService.
+*/
+
+#include "nsCOMPtr.h"
+#include "nsAppShellCIDs.h"
+#include "nsIAppShellService.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIServiceManager.h"
+#include "nsIXULWindow.h"
+#include "nsIWebBrowserChrome.h"
+#include "nsWindowCreator.h"
+
+static NS_DEFINE_CID(kAppShellServiceCID, NS_APPSHELL_SERVICE_CID);
+
+nsWindowCreator::nsWindowCreator() {
+  NS_INIT_REFCNT();
+}
+
+nsWindowCreator::~nsWindowCreator() {
+}
+
+NS_IMPL_ISUPPORTS1(nsWindowCreator, nsIWindowCreator)
+
+NS_IMETHODIMP
+nsWindowCreator::CreateWindow(nsIWebBrowserChrome *aParent,
+                              PRUint32 aChromeFlags,
+                              nsIWebBrowserChrome **_retval)
+{
+  NS_ENSURE_ARG_POINTER(_retval);
+  *_retval = 0;
+
+  /* There is no valid way to get from an nsIWebBrowserChrome interface
+     to the corresponding nsXULWindow, so we can't really service a request
+     to make a window with a parent. This shouldn't be a problem, since
+     convention suggests this method only be used when there is no parent
+     window (otherwise, just call Open() on the parent). However, we
+     should say something, just to be sure: */
+  if (aParent || (aChromeFlags & nsIWebBrowserChrome::CHROME_DEPENDENT))
+    return NS_ERROR_INVALID_ARG;
+
+  nsCOMPtr<nsIAppShellService> appShell(do_GetService(kAppShellServiceCID));
+  if (!appShell)
+    return NS_ERROR_FAILURE;
+  
+  nsCOMPtr<nsIXULWindow> newWindow;
+  appShell->CreateTopLevelWindow(0, 0, PR_FALSE, PR_FALSE,
+    aChromeFlags, NS_SIZETOCONTENT, NS_SIZETOCONTENT,
+    getter_AddRefs(newWindow));
+
+  nsCOMPtr<nsIInterfaceRequestor> thing(do_QueryInterface(newWindow));
+  if (thing)
+    thing->GetInterface(NS_GET_IID(nsIWebBrowserChrome), (void **) _retval);
+
+  return *_retval ? NS_OK : NS_ERROR_FAILURE;
+}
+

xpfe/bootstrap/nsWindowCreator.h

@@ -0,0 +1,40 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 2001 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ */
+
+#ifndef __nsWindowCreator_h_
+#define __nsWindowCreator_h_
+
+#include "nsIWindowCreator.h"
+
+class nsWindowCreator :
+      public nsIWindowCreator
+{
+public:
+  nsWindowCreator();
+  virtual ~nsWindowCreator();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIWINDOWCREATOR
+};
+
+#endif
+