InstantExtended: Committed NTP

chrome/browser/instant/instant_page.h

+// Copyright 2013 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 CHROME_BROWSER_INSTANT_INSTANT_PAGE_H_
+#define CHROME_BROWSER_INSTANT_INSTANT_PAGE_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/string16.h"
+#include "chrome/common/instant_types.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/common/page_transition_types.h"
+
+class GURL;
+
+namespace chrome {
+namespace search {
+struct Mode;
+}
+}
+
+namespace content {
+class WebContents;
+}
+
+namespace gfx {
+class Rect;
+}
+
+// InstantPage is used to exchange messages with a page that implements the
+// Instant/Embedded Search API (http://dev.chromium.org/embeddedsearch).
+// InstantPage is not used directly but via one of its derived classes:
+// InstantOverlay, InstantNTP and InstantTab.
+class InstantPage : public content::WebContentsObserver {
+ public:
+  // InstantPage calls its delegate in response to messages received from the
+  // page. Each method is called with the |contents| corresponding to the page
+  // we are observing.
+  class Delegate {
+   public:
+    // Called when a RenderView is created, so that state can be initialized.
+    virtual void InstantPageRenderViewCreated(
+        const content::WebContents* contents) = 0;
+
+    // Called upon determination of Instant API support. Either in response to
+    // the page loading or because we received some other message.
+    virtual void InstantSupportDetermined(const content::WebContents* contents,
+                                          bool supports_instant) = 0;
+
+    // Called when the underlying RenderView crashed.
+    virtual void InstantPageRenderViewGone(
+        const content::WebContents* contents) = 0;
+
+    // Called when the page is about to navigate to |url|.
+    virtual void InstantPageAboutToNavigateMainFrame(
+        const content::WebContents* contents,
+        const GURL& url) = 0;
+
+    // Called when the page has suggestions. Usually in response to Update(),
+    // SendAutocompleteResults() or UpOrDownKeyPressed().
+    virtual void SetSuggestions(
+        const content::WebContents* contents,
+        const std::vector<InstantSuggestion>& suggestions) = 0;
+
+    // Called when the page wants to be shown. Usually in response to Update(),
+    // SendAutocompleteResults() or SearchModeChanged().
+    virtual void ShowInstantPreview(const content::WebContents* contents,
+                                    InstantShownReason reason,
+                                    int height,
+                                    InstantSizeUnits units) = 0;
+
+    // Called when the page wants the omnibox to start capturing user key
+    // strokes. If this call is processed successfully, the omnibox will not
+    // look focused visibly but any user key strokes will go to the omnibox.
+    // Currently, this is implemented by focusing the omnibox invisibly.
+    virtual void StartCapturingKeyStrokes(
+        const content::WebContents* contents) = 0;
+
+    // Called when the page wants the omnibox to stop capturing user key
+    // strokes.
+    virtual void StopCapturingKeyStrokes(content::WebContents* contents) = 0;
+
+    // Called when the page wants to navigate to the specified URL. Usually
+    // used by the page to navigate to privileged destinations (e.g. chrome://
+    // URLs) or to navigate to URLs that are hidden from the page using
+    // Restricted IDs (rid in the API).
+    virtual void NavigateToURL(const content::WebContents* contents,
+                               const GURL& url,
+                               content::PageTransition transition) = 0;
+
+   protected:
+    virtual ~Delegate();
+  };
+
+  virtual ~InstantPage();
+
+  // The WebContents corresponding to the page we're talking to. May be NULL.
+  content::WebContents* contents() const { return contents_; }
+
+  // Returns true if the page is known to support the Instant API. This starts
+  // out false, and is set to true whenever we get any message from the page.
+  // Once true, it never becomes false (the page isn't expected to drop API
+  // support suddenly).
+  bool supports_instant() const { return supports_instant_; }
+
+  // Tells the page that the user typed |text| into the omnibox. If |verbatim|
+  // is false, the page predicts the query the user means to type and fetches
+  // results for the prediction. If |verbatim| is true, |text| is taken as the
+  // exact query (no prediction is made).
+  virtual void Update(const string16& text,
+                      size_t selection_start,
+                      size_t selection_end,
+                      bool verbatim);
+
+  // Tells the page that the user pressed Enter in the omnibox.
+  void Submit(const string16& text);
+
+  // Tells the page that the user clicked on it. Nothing is being cancelled; the
+  // poor choice of name merely reflects the IPC of the same (poor) name.
+  void Cancel(const string16& text);
+
+  // Tells the page the bounds of the omnibox dropdown (in screen coordinates).
+  // This is used by the page to offset the results to avoid them being covered
+  // by the omnibox dropdown.
+  void SetPopupBounds(const gfx::Rect& bounds);
+
+  // Tells the page the start and end margins of the omnibox (in screen
+  // coordinates). This is used by the page to align text or assets properly
+  // with the omnibox.
+  void SetMarginSize(int start, int end);
+
+  // Tells the page about the font information.
+  void InitializeFonts();
+
+  // Tells the renderer to determine if the page supports the Instant API, which
+  // results in a call to InstantSupportDetermined() when the reply is received.
+  void DetermineIfPageSupportsInstant();
+
+  // Tells the page about the available autocomplete results.
+  void SendAutocompleteResults(
+      const std::vector<InstantAutocompleteResult>& results);
+
+  // Tells the page that the user pressed Up or Down in the omnibox. |count| is
+  // a repeat count, negative for moving up, positive for moving down.
+  void UpOrDownKeyPressed(int count);
+
+  // Tells the page that the active tab's search mode has changed.
+  void SearchModeChanged(const chrome::search::Mode& mode);
+
+  // Tells the page about the current theme background.
+  void SendThemeBackgroundInfo(const ThemeBackgroundInfo& theme_info);
+
+  // Tells the page about the current theme area height.
+  void SendThemeAreaHeight(int height);
+
+  // Tells the page whether it is allowed to display Instant results.
+  void SetDisplayInstantResults(bool display_instant_results);
+
+  // Tells the page whether the browser is capturing user key strokes.
+  void KeyCaptureChanged(bool is_key_capture_enabled);
+
+ protected:
+  explicit InstantPage(Delegate* delegate);
+
+  // Sets |contents| as the page to communicate with. |contents| may be NULL,
+  // which effectively stops all communication.
+  void SetContents(content::WebContents* contents);
+
+  Delegate* delegate() const { return delegate_; }
+
+  // These functions are called before processing messages received from the
+  // page. By default, all messages are handled, but any derived classes may
+  // choose to ingore some or all of the received messages by overriding these
+  // methods.
+  virtual bool ShouldProcessRenderViewCreated();
+  virtual bool ShouldProcessRenderViewGone();
+  virtual bool ShouldProcessAboutToNavigateMainFrame();
+  virtual bool ShouldProcessSetSuggestions();
+  virtual bool ShouldProcessShowInstantPreview();
+  virtual bool ShouldProcessStartCapturingKeyStrokes();
+  virtual bool ShouldProcessStopCapturingKeyStrokes();
+  virtual bool ShouldProcessNavigateToURL();

[sreeram, 2013/02/07 18:22:46]

It might be nice to flip the default from true to false. While reviewing this
CL, I often found myself doing a diff from the list here to the list that's
overridden by each subclass to see what's actually being handled, because that's
what matters (more than what they don't handle).

[samarth, 2013/02/07 22:11:55]

Yeah, that's much nicer. Done.

+
+ private:
+  // Overridden from content::WebContentsObserver:
+  virtual void RenderViewCreated(
+      content::RenderViewHost* render_view_host) OVERRIDE;
+  virtual void DidFinishLoad(
+      int64 frame_id,
+      const GURL& validated_url,
+      bool is_main_frame,
+      content::RenderViewHost* render_view_host) OVERRIDE;
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+  virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;
+  virtual void DidCommitProvisionalLoadForFrame(
+      int64 frame_id,
+      bool is_main_frame,
+      const GURL& url,
+      content::PageTransition transition_type,
+      content::RenderViewHost* render_view_host) OVERRIDE;
+
+  void OnSetSuggestions(int page_id,
+                        const std::vector<InstantSuggestion>& suggestions);
+  void OnInstantSupportDetermined(int page_id, bool supports_instant);
+  void OnShowInstantPreview(int page_id,
+                            InstantShownReason reason,
+                            int height,
+                            InstantSizeUnits units);
+  void OnStartCapturingKeyStrokes(int page_id);
+  void OnStopCapturingKeyStrokes(int page_id);
+  void OnSearchBoxNavigate(int page_id, const GURL& url,
+                           content::PageTransition transition);
+
+  Delegate* const delegate_;
+  content::WebContents* contents_;
+  bool supports_instant_;
+
+  DISALLOW_COPY_AND_ASSIGN(InstantPage);
+};
+
+#endif  // CHROME_BROWSER_INSTANT_INSTANT_PAGE_H_