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 ASH_MAGNIFIER_PARTIAL_MAGNIFICATION_CONTROLLER_H_ 6 #define ASH_MAGNIFIER_PARTIAL_MAGNIFICATION_CONTROLLER_H_ 7 8 #include "ui/aura/window_observer.h" 9 #include "ui/events/event_handler.h" 10 #include "ui/gfx/point.h" 11 #include "ui/views/widget/widget_observer.h" 12 13 namespace ash { 14 15 const float kDefaultPartialMagnifiedScale = 1.5f; 16 const float kNonPartialMagnifiedScale = 1.0f; 17 18 // Controls the partial screen magnifier, which is a small area of the screen 19 // which is zoomed in. The zoomed area follows the mouse cursor when enabled. 20 class PartialMagnificationController 21 : public ui::EventHandler, 22 public aura::WindowObserver, 23 public views::WidgetObserver { 24 public: 25 PartialMagnificationController(); 26 virtual ~PartialMagnificationController(); 27 28 // Enables (or disables if |enabled| is false) partial screen magnifier 29 // feature. 30 virtual void SetEnabled(bool enabled); 31 is_enabled()32 bool is_enabled() const { return is_enabled_; } 33 34 // Sets the magnification ratio. 1.0f means no magnification. 35 void SetScale(float scale); 36 37 // Returns the current magnification ratio. GetScale()38 float GetScale() const { return scale_; } 39 40 private: 41 void OnMouseMove(const gfx::Point& location_in_root); 42 43 // Switch PartialMagnified RootWindow to |new_root_window|. This does 44 // following: 45 // - Remove the magnifier from the current root window. 46 // - Create a magnifier in the new root_window |new_root_window|. 47 // - Switch the target window from current window to |new_root_window|. 48 void SwitchTargetRootWindow(aura::Window* new_root_window); 49 50 // Returns the root window that contains the mouse cursor. 51 aura::Window* GetCurrentRootWindow(); 52 53 // Return true if the magnification scale > kMinPartialMagnifiedScaleThreshold 54 bool IsPartialMagnified() const; 55 56 // Create the magnifier window. 57 void CreateMagnifierWindow(); 58 59 // Cleans up the window if needed. 60 void CloseMagnifierWindow(); 61 62 // Removes this as an observer of the zoom widget and the root window. 63 void RemoveZoomWidgetObservers(); 64 65 // ui::EventHandler overrides: 66 virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE; 67 68 // Overridden from WindowObserver: 69 virtual void OnWindowDestroying(aura::Window* window) OVERRIDE; 70 71 // Overridden from WidgetObserver: 72 virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE; 73 74 // True if the magnified window is in motion of zooming or un-zooming effect. 75 // Otherwise, false. 76 bool is_on_zooming_; 77 78 bool is_enabled_; 79 80 // Current scale, origin (left-top) position of the magnification window. 81 float scale_; 82 gfx::Point origin_; 83 84 views::Widget* zoom_widget_; 85 86 DISALLOW_COPY_AND_ASSIGN(PartialMagnificationController); 87 }; 88 89 } // namespace ash 90 91 #endif // ASH_MAGNIFIER_PARTIAL_MAGNIFICATION_CONTROLLER_H_ 92