components/web_view/navigation_controller.h

   1 // Copyright 2015 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 COMPONENTS_WEB_VIEW_NAVIGATION_CONTROLLER_H_
   6 #define COMPONENTS_WEB_VIEW_NAVIGATION_CONTROLLER_H_
   7
   8 #include "base/memory/scoped_vector.h"
   9
  10 #include "components/web_view/public/interfaces/web_view.mojom.h"
  11
  12 namespace web_view {
  13
  14 class Frame;
  15 class NavigationEntry;
  16 class NavigationControllerDelegate;
  17 enum class ReloadType;
  18
  19 // A NavigationController maintains the back-forward list for a WebView and
  20 // manages all navigation within that list.
  21 //
  22 // Each NavigationController belongs to one WebContents; each WebContents has
  23 // exactly one NavigationController.
  24 class NavigationController {
  25  public:
  26   explicit NavigationController(NavigationControllerDelegate* delegate);
  27   ~NavigationController();
  28
  29   int GetCurrentEntryIndex() const;
  30   int GetIndexForOffset(int offset) const;
  31   int GetEntryCount() const;
  32   NavigationEntry* GetEntryAtIndex(int index) const;
  33   NavigationEntry* GetEntryAtOffset(int offset) const;
  34   bool CanGoBack() const;
  35   bool CanGoForward() const;
  36   bool CanGoToOffset(int offset) const;
  37
  38   void GoBack();
  39   void GoForward();
  40
  41   void LoadURL(mojo::URLRequestPtr request);
  42
  43   void NavigateToPendingEntry(ReloadType reload_type);
  44
  45   // Takes ownership of a pending entry, and adds it to the current list.
  46   //
  47   // TODO(erg): This should eventually own the navigation transition like
  48   // content::NavigationControllerImpl::NavigateToPendingEntry() does.
  49   void SetPendingEntry(scoped_ptr<NavigationEntry> entry);
  50
  51   // Discards only the pending entry. |was_failure| should be set if the pending
  52   // entry is being discarded because it failed to load.
  53   void DiscardPendingEntry(bool was_failure);
  54
  55   // Called when a frame is committed.
  56   void FrameDidCommitProvisionalLoad(Frame* frame);
  57
  58  private:
  59   using NavigationEntries = ScopedVector<NavigationEntry>;
  60   NavigationEntries entries_;
  61
  62   // An entry we haven't gotten a response for yet.  This will be discarded
  63   // when we navigate again.  It's used only so we know what the currently
  64   // displayed tab is.
  65   //
  66   // This may refer to an item in the entries_ list if the pending_entry_index_
  67   // == -1, or it may be its own entry that should be deleted. Be careful with
  68   // the memory management.
  69   NavigationEntry* pending_entry_;
  70
  71   // The index of the currently visible entry.
  72   int last_committed_entry_index_;
  73
  74   // The index of the pending entry if it is in entries_, or -1 if
  75   // pending_entry_ is a new entry (created by LoadURL).
  76   int pending_entry_index_;
  77
  78   NavigationControllerDelegate* delegate_;
  79
  80   DISALLOW_COPY_AND_ASSIGN(NavigationController);
  81 };
  82
  83 }  // namespace web_view
  84
  85 #endif  // COMPONENTS_WEB_VIEW_NAVIGATION_CONTROLLER_H_