1 // Copyright (c) 2011 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 // Handles the visible notification (or balloons). 6 7 #ifndef CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_ 8 #define CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_ 9 #pragma once 10 11 #include <deque> 12 13 #include "base/basictypes.h" 14 #include "base/message_loop.h" 15 #include "chrome/browser/notifications/balloon_collection.h" 16 #include "chrome/browser/notifications/balloon_collection_base.h" 17 #include "ui/gfx/point.h" 18 #include "ui/gfx/rect.h" 19 20 // Mac balloons grow from the top down and have close buttons on top, so 21 // offsetting is not necessary for easy multiple-closing. Other platforms grow 22 // from the bottom up and have close buttons on top, so it is necessary. 23 #if defined(OS_MACOSX) 24 #define USE_OFFSETS 0 25 #else 26 #define USE_OFFSETS 1 27 #endif 28 29 // A balloon collection represents a set of notification balloons being 30 // shown on the screen. It positions new notifications according to 31 // a layout, and monitors for balloons being closed, which it reports 32 // up to its parent, the notification UI manager. 33 class BalloonCollectionImpl : public BalloonCollection 34 #if USE_OFFSETS 35 , public MessageLoopForUI::Observer 36 #endif 37 { 38 public: 39 BalloonCollectionImpl(); 40 virtual ~BalloonCollectionImpl(); 41 42 // BalloonCollection interface. 43 virtual void Add(const Notification& notification, 44 Profile* profile); 45 virtual bool RemoveById(const std::string& id); 46 virtual bool RemoveBySourceOrigin(const GURL& source_origin); 47 virtual void RemoveAll(); 48 virtual bool HasSpace() const; 49 virtual void ResizeBalloon(Balloon* balloon, const gfx::Size& size); 50 virtual void SetPositionPreference(PositionPreference position); 51 virtual void DisplayChanged(); 52 virtual void OnBalloonClosed(Balloon* source); 53 virtual const Balloons& GetActiveBalloons(); 54 55 // MessageLoopForUI::Observer interface. 56 #if defined(OS_WIN) WillProcessMessage(const MSG & event)57 virtual void WillProcessMessage(const MSG& event) {} 58 virtual void DidProcessMessage(const MSG& event); 59 #endif 60 #if defined(OS_LINUX) WillProcessEvent(GdkEvent * event)61 virtual void WillProcessEvent(GdkEvent* event) {} 62 virtual void DidProcessEvent(GdkEvent* event); 63 #endif 64 65 protected: 66 // Calculates layout values for the balloons including 67 // the scaling, the max/min sizes, and the upper left corner of each. 68 class Layout { 69 public: 70 Layout(); 71 72 // These enumerations all are based on a screen orientation where 73 // the origin is the top-left. 74 enum Placement { 75 INVALID, 76 VERTICALLY_FROM_TOP_LEFT, 77 VERTICALLY_FROM_TOP_RIGHT, 78 VERTICALLY_FROM_BOTTOM_LEFT, 79 VERTICALLY_FROM_BOTTOM_RIGHT 80 }; 81 82 // Refresh the work area and balloon placement. 83 void OnDisplaySettingsChanged(); 84 85 // TODO(johnnyg): Scale the size to account for the system font factor. min_balloon_width()86 static int min_balloon_width() { return kBalloonMinWidth; } max_balloon_width()87 static int max_balloon_width() { return kBalloonMaxWidth; } min_balloon_height()88 static int min_balloon_height() { return kBalloonMinHeight; } max_balloon_height()89 static int max_balloon_height() { return kBalloonMaxHeight; } 90 91 // Utility function constrains the input rectangle to the min and max sizes. 92 static gfx::Size ConstrainToSizeLimits(const gfx::Size& rect); 93 set_placement(Placement placement)94 void set_placement(Placement placement) { placement_ = placement; } 95 96 // Returns both the total space available and the maximum 97 // allowed per balloon. 98 // 99 // The size may be a height or length depending on the way that 100 // balloons are laid out. 101 void GetMaxLinearSize(int* max_balloon_size, int* total_size) const; 102 103 // Refresh the cached values for work area and drawing metrics. 104 // The application should call this method to re-acquire metrics after 105 // any resolution or settings change. 106 // Returns true if and only if a metric changed. 107 bool RefreshSystemMetrics(); 108 109 // Returns the origin for the sequence of balloons depending on layout. 110 // Should not be used to place a balloon -- only to call NextPosition(). 111 gfx::Point GetLayoutOrigin() const; 112 113 // Compute the position for the next balloon. 114 // Start with *position_iterator = GetLayoutOrigin() and call repeatedly 115 // to get a sequence of positions. Return value is the upper-left coordinate 116 // for each next balloon. 117 gfx::Point NextPosition(const gfx::Size& balloon_size, 118 gfx::Point* position_iterator) const; 119 120 // Return a offscreen location which is offscreen for this layout, 121 // to be used as the initial position for an animation into view. 122 gfx::Point OffScreenLocation() const; 123 124 // Returns true if the layout requires offsetting for keeping the close 125 // buttons under the cursor during rapid-close interaction. 126 bool RequiresOffsets() const; 127 128 private: 129 // Layout parameters 130 int VerticalEdgeMargin() const; 131 int HorizontalEdgeMargin() const; 132 int InterBalloonMargin() const; 133 134 // Minimum and maximum size of balloon content. 135 static const int kBalloonMinWidth = 300; 136 static const int kBalloonMaxWidth = 300; 137 static const int kBalloonMinHeight = 24; 138 static const int kBalloonMaxHeight = 160; 139 140 Placement placement_; 141 gfx::Rect work_area_; 142 DISALLOW_COPY_AND_ASSIGN(Layout); 143 }; 144 145 // Creates a new balloon. Overridable by unit tests. The caller is 146 // responsible for freeing the pointer returned. 147 virtual Balloon* MakeBalloon(const Notification& notification, 148 Profile* profile); 149 150 // Gets a bounding box for all the current balloons in screen coordinates. 151 gfx::Rect GetBalloonsBoundingBox() const; 152 153 private: 154 // Adjusts the positions of the balloons (e.g., when one is closed). 155 // Implemented by each platform for specific UI requirements. 156 void PositionBalloons(bool is_reposition); 157 158 // Cross-platform internal implementation for PositionBalloons. 159 void PositionBalloonsInternal(bool is_reposition); 160 161 #if defined(OS_MACOSX) 162 // Get the work area on Mac OS, without inverting the coordinates. 163 static gfx::Rect GetMacWorkArea(); 164 #endif 165 166 // Base implementation for the collection of active balloons. 167 BalloonCollectionBase base_; 168 169 // The layout parameters for balloons in this collection. 170 Layout layout_; 171 172 #if USE_OFFSETS 173 // Start and stop observing all UI events. 174 void AddMessageLoopObserver(); 175 void RemoveMessageLoopObserver(); 176 177 // Cancel all offset and reposition the balloons normally. 178 void CancelOffsets(); 179 180 // Handles a mouse motion while the balloons are temporarily offset. 181 void HandleMouseMoveEvent(); 182 183 // Is the current cursor in the balloon area? 184 bool IsCursorInBalloonCollection() const; 185 186 // Factory for generating delayed reposition tasks on mouse motion. 187 ScopedRunnableMethodFactory<BalloonCollectionImpl> reposition_factory_; 188 189 // Is the balloon collection currently listening for UI events? 190 bool added_as_message_loop_observer_; 191 #endif 192 193 DISALLOW_COPY_AND_ASSIGN(BalloonCollectionImpl); 194 }; 195 196 #endif // CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_ 197