1 // Copyright (c) 2012 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 UI_VIEWS_VIEW_MODEL_H_ 6 #define UI_VIEWS_VIEW_MODEL_H_ 7 8 #include <vector> 9 10 #include "base/basictypes.h" 11 #include "base/logging.h" 12 #include "ui/gfx/rect.h" 13 #include "ui/views/views_export.h" 14 15 namespace views { 16 17 class View; 18 19 // ViewModel is used to track an 'interesting' set of a views. Often times 20 // during animations views are removed after a delay, which makes for tricky 21 // coordinate conversion as you have to account for the possibility of the 22 // indices from the model not lining up with those you expect. This class lets 23 // you define the 'interesting' views and operate on those views. 24 class VIEWS_EXPORT ViewModel { 25 public: 26 ViewModel(); 27 ~ViewModel(); 28 29 // Adds |view| to this model. This does not add |view| to a view hierarchy, 30 // only to this model. 31 void Add(View* view, int index); 32 33 // Removes the view at the specified index. This does not actually remove the 34 // view from the view hierarchy. 35 void Remove(int index); 36 37 // Moves the view at |index| to |target_index|. |target_index| is in terms 38 // of the model *after* the view at |index| is removed. 39 void Move(int index, int target_index); 40 41 // Variant of Move() that leaves the bounds as is. That is, after invoking 42 // this the bounds of the view at |target_index| (and all other indices) are 43 // exactly the same as the bounds of the view at |target_index| before 44 // invoking this. 45 void MoveViewOnly(int index, int target_index); 46 47 // Returns the number of views. 48 int view_size() const { return static_cast<int>(entries_.size()); } 49 50 // Removes and deletes all the views. 51 void Clear(); 52 53 // Returns the view at the specified index. 54 View* view_at(int index) const { 55 check_index(index); 56 return entries_[index].view; 57 } 58 59 void set_ideal_bounds(int index, const gfx::Rect& bounds) { 60 check_index(index); 61 entries_[index].ideal_bounds = bounds; 62 } 63 64 const gfx::Rect& ideal_bounds(int index) const { 65 check_index(index); 66 return entries_[index].ideal_bounds; 67 } 68 69 // Returns the index of the specified view, or -1 if the view isn't in the 70 // model. 71 int GetIndexOfView(const View* view) const; 72 73 private: 74 struct Entry { 75 Entry() : view(NULL) {} 76 77 View* view; 78 gfx::Rect ideal_bounds; 79 }; 80 typedef std::vector<Entry> Entries; 81 82 #if !defined(NDEBUG) 83 void check_index(int index) const { 84 DCHECK_LT(index, static_cast<int>(entries_.size())); 85 DCHECK_GE(index, 0); 86 } 87 #else 88 void check_index(int index) const {} 89 #endif 90 91 Entries entries_; 92 93 DISALLOW_COPY_AND_ASSIGN(ViewModel); 94 }; 95 96 } // namespace views 97 98 #endif // UI_VIEWS_VIEW_MODEL_H_ 99
