[WebModals] New API for browser-scoped popup management.

components/web_modal/single_popup_manager.h

+// Copyright 2014 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.
+
+#ifndef COMPONENTS_WEB_MODAL_SINGLE_POPUP_MANAGER_H_
+#define COMPONENTS_WEB_MODAL_SINGLE_POPUP_MANAGER_H_
+
+#include "components/web_modal/native_web_contents_modal_dialog.h"
+
+namespace content {
+class WebContents;
+}
+
+namespace web_modal {
+
+// Interface from SinglePopupManager to PopupManager.
+class SinglePopupManagerDelegate {

[Finnur, 2014/06/30 13:53:36]

I kind of would have expected to see this class within the SinglePopupManager
class (SinglePopupManager::Delegate as opposed to SinglePopupManagerDelegate).
Any particular reason for it being free-standing?

[Greg Billock, 2014/07/01 00:53:05]

Not really. It's descending from the modal dlg mgr structure, is all.

+ public:
+  SinglePopupManagerDelegate() {}
+  virtual ~SinglePopupManagerDelegate() {}
+
+  // Notify the delegate that the dialog is closing. The
+  // calling SinglePopupManager will be deleted before the end of this call.
+  virtual void WillClose(NativePopup popup) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SinglePopupManagerDelegate);
+};
+
+// Provides an interface for platform-specific UI implementation for popups.
+// Each object will manage a single NativePopup window during its lifecycle.
+// The rule of thumb is that only one popup will be shown at a time per tab.
+// (Exceptions exist.)
+//
+// Implementation classes should accept a NativePopup at construction time
+// and register to be notified when the dialog is closing, so that it can
+// notify its delegate (WillClose method).
+class SinglePopupManager {
+ public:
+  virtual ~SinglePopupManager() {}
+
+  // If the manager returns non-null to this call, it is bound to a particular
+  // tab and will be hidden and shown if that tab visibility changes.
+  virtual content::WebContents* GetBoundWebContents() = 0;
+
+  // Makes the popup visible.
+  virtual void Show() = 0;
+
+  // Hides the popup without closing it.
+  virtual void Hide() = 0;
+
+  // Closes the popup.
+  // This method must call WillClose() on the delegate.
+  // Important note: this object will be deleted at the close of that
+  // invocation.
+  virtual void Close() = 0;
+
+  // Sets focus on the popup.
+  virtual void Focus() = 0;
+
+  virtual void Pulse() = 0;

[Finnur, 2014/06/30 13:53:36]

nit: Pulsate the popup, in order to draw the user's attention to it.

[Greg Billock, 2014/07/01 00:53:05]

Done.

+
+  // Returns the popup under management by this object.
+  virtual NativePopup popup() = 0;
+
+  // Returns true if the popup under management was initiated by a user
+  // gesture. When this is true, the popup manager will hide any existing
+  // popups and move the newly-created NativePopup to the top of the display
+  // queue.
+  virtual bool HasUserGesture() = 0;
+
+  // Returns true if the popup under management is tolerant of being overlapped
+  // by other popups. This may be true for large web-modals which cover most of
+  // the window real estate (e.g. print preview).
+  virtual bool MayBeOverlapped() = 0;
+
+  // Returns true if the popup under management should close if there is a
+  // navigation underneath it, including the showing of any interstitial
+  // content. Popups which relate to the web content being displayed will
+  // ordinarily set this to true.
+  // TODO(gbillock): should be generalized in code location or by splitting
+  // the API to support the same-origin logic in WCMDM::DidNavigateMainFrame.
+  // TBD right now because we're not sure which knobs need to be set here.
+  virtual bool ShouldCloseOnNavigation() = 0;
+
+ protected:
+  SinglePopupManager() {}

[Finnur, 2014/06/30 13:53:36]

nit: You have two ctors and two dtors in this .h file. I believe erg (or
someone) did a pass at the codebase a while back to aggressively move these into
a .cc file, to save on binary size -- otherwise the implementation of the
default con-/de-structors would be copied to all the locations that use this
class. By having a .cc you have one unit for that code. I know these classes
don't (at least yet) contain much complexity in the implementation of the ctors
and dtors, but you never know what happens in the future. Anyway, just thought
I'd mention it since there's very little downsides, only upsides. 

[Greg Billock, 2014/07/01 00:53:05]

These are interface stubs, which my impression was weren't nearly as heavy. I
don't object to moving them, though.

+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SinglePopupManager);
+};
+
+}  // namespace web_modal
+
+#endif  // COMPONENTS_WEB_MODAL_SINGLE_POPUP_MANAGER_H_