chrome/browser/ui/search/instant_page.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_UI_SEARCH_INSTANT_PAGE_H_
   6 #define CHROME_BROWSER_UI_SEARCH_INSTANT_PAGE_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/gtest_prod_util.h"
  13 #include "base/strings/string16.h"
  14 #include "chrome/browser/ui/search/search_model_observer.h"
  15 #include "content/public/browser/web_contents_observer.h"
  16 #include "ui/base/page_transition_types.h"
  17
  18 class GURL;
  19 class Profile;
  20
  21 namespace content {
  22 struct FrameNavigateParams;
  23 struct LoadCommittedDetails;
  24 class WebContents;
  25 }
  26
  27 namespace gfx {
  28 class Rect;
  29 }
  30
  31 // InstantPage is used to exchange messages with a page that implements the
  32 // Instant/Embedded Search API (http://dev.chromium.org/embeddedsearch).
  33 // InstantPage is not used directly but via one of its derived classes,
  34 // InstantNTP and InstantTab.
  35 class InstantPage : public content::WebContentsObserver,
  36                     public SearchModelObserver {
  37  public:
  38   // InstantPage calls its delegate in response to messages received from the
  39   // page. Each method is called with the |contents| corresponding to the page
  40   // we are observing.
  41   class Delegate {
  42    public:
  43     // Called upon determination of Instant API support. Either in response to
  44     // the page loading or because we received some other message.
  45     virtual void InstantSupportDetermined(const content::WebContents* contents,
  46                                           bool supports_instant) = 0;
  47
  48     // Called when the page is about to navigate to |url|.
  49     virtual void InstantPageAboutToNavigateMainFrame(
  50         const content::WebContents* contents,
  51         const GURL& url) = 0;
  52
  53    protected:
  54     virtual ~Delegate();
  55   };
  56
  57   ~InstantPage() override;
  58
  59   // Returns the Instant URL that was loaded for this page. Returns the empty
  60   // string if no URL was explicitly loaded as is the case for InstantTab.
  61   virtual const std::string& instant_url() const;
  62
  63   // Returns true if the page is known to support the Instant API. This starts
  64   // out false, and is set to true whenever we get any message from the page.
  65   // Once true, it never becomes false (the page isn't expected to drop API
  66   // support suddenly).
  67   virtual bool supports_instant() const;
  68
  69   // Returns true if the page is the local NTP (i.e. its URL is
  70   // chrome::kChromeSearchLocalNTPURL).
  71   virtual bool IsLocal() const;
  72
  73  protected:
  74   InstantPage(Delegate* delegate,
  75               const std::string& instant_url,
  76               Profile* profile);
  77
  78   // Sets |web_contents| as the page to communicate with. |web_contents| may be
  79   // NULL, which effectively stops all communication.
  80   void SetContents(content::WebContents* web_contents);
  81
  82   Delegate* delegate() const { return delegate_; }
  83
  84   Profile* profile() const { return profile_; }
  85
  86   // These functions are called before processing messages received from the
  87   // page. By default, all messages are handled, but any derived classes may
  88   // choose to ignore some or all of the received messages by overriding these
  89   // methods.
  90   virtual bool ShouldProcessAboutToNavigateMainFrame();
  91
  92  private:
  93   FRIEND_TEST_ALL_PREFIXES(InstantPageTest, IsLocal);
  94   FRIEND_TEST_ALL_PREFIXES(InstantPageTest,
  95                            DetermineIfPageSupportsInstant_Local);
  96   FRIEND_TEST_ALL_PREFIXES(InstantPageTest,
  97                            DetermineIfPageSupportsInstant_NonLocal);
  98   FRIEND_TEST_ALL_PREFIXES(InstantPageTest,
  99                            PageURLDoesntBelongToInstantRenderer);
 100   FRIEND_TEST_ALL_PREFIXES(InstantPageTest, PageSupportsInstant);
 101
 102   // Overridden from content::WebContentsObserver:
 103   void DidCommitProvisionalLoadForFrame(
 104       content::RenderFrameHost* render_frame_host,
 105       const GURL& url,
 106       ui::PageTransition transition_type) override;
 107
 108   // Overridden from SearchModelObserver:
 109   void ModelChanged(const SearchModel::State& old_state,
 110                     const SearchModel::State& new_state) override;
 111
 112   // Update the status of Instant support.
 113   void InstantSupportDetermined(bool supports_instant);
 114
 115   void ClearContents();
 116
 117   // TODO(kmadhusu): Remove |profile_| from here and update InstantNTP to get
 118   // |profile| from InstantNTPPrerenderer.
 119   Profile* profile_;
 120
 121   Delegate* const delegate_;
 122   const std::string instant_url_;
 123
 124   DISALLOW_COPY_AND_ASSIGN(InstantPage);
 125 };
 126
 127 #endif  // CHROME_BROWSER_UI_SEARCH_INSTANT_PAGE_H_