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/base/events/event_handler.h" 10 #include "ui/gfx/point.h" 11 #include "ui/views/widget/widget_observer.h" 12 13 namespace aura { 14 class RootWindow; 15 } 16 17 namespace ash { 18 19 const float kDefaultPartialMagnifiedScale = 1.5f; 20 const float kNonPartialMagnifiedScale = 1.0f; 21 22 // Controls the partial screen magnifier, which is a small area of the screen 23 // which is zoomed in. The zoomed area follows the mouse cursor when enabled. 24 class PartialMagnificationController 25 : public ui::EventHandler, 26 public aura::WindowObserver, 27 public views::WidgetObserver { 28 public: 29 PartialMagnificationController(); 30 virtual ~PartialMagnificationController(); 31 32 // Enables (or disables if |enabled| is false) partial screen magnifier 33 // feature. 34 virtual void SetEnabled(bool enabled); 35 36 bool is_enabled() const { return is_enabled_; } 37 38 // Sets the magnification ratio. 1.0f means no magnification. 39 void SetScale(float scale); 40 41 // Returns the current magnification ratio. 42 float GetScale() const { return scale_; } 43 44 private: 45 void OnMouseMove(const gfx::Point& location_in_root); 46 47 // Switch PartialMagnified RootWindow to |new_root_window|. This does 48 // following: 49 // - Remove the magnifier from the current root window. 50 // - Create a magnifier in the new root_window |new_root_window|. 51 // - Switch the target window from current window to |new_root_window|. 52 void SwitchTargetRootWindow(aura::RootWindow* new_root_window); 53 54 // Returns the root window that contains the mouse cursor. 55 aura::RootWindow* GetCurrentRootWindow(); 56 57 // Return true if the magnification scale > kMinPartialMagnifiedScaleThreshold 58 bool IsPartialMagnified() const; 59 60 // Create the magnifier window. 61 void CreateMagnifierWindow(); 62 63 // Cleans up the window if needed. 64 void CloseMagnifierWindow(); 65 66 // Removes this as an observer of the zoom widget and the root window. 67 void RemoveZoomWidgetObservers(); 68 69 // ui::EventHandler overrides: 70 virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE; 71 72 // Overridden from WindowObserver: 73 virtual void OnWindowDestroying(aura::Window* window) OVERRIDE; 74 75 // Overridden from WidgetObserver: 76 virtual void OnWidgetDestroying(views::Widget* widget) OVERRIDE; 77 78 // True if the magnified window is in motion of zooming or un-zooming effect. 79 // Otherwise, false. 80 bool is_on_zooming_; 81 82 bool is_enabled_; 83 84 // Current scale, origin (left-top) position of the magnification window. 85 float scale_; 86 gfx::Point origin_; 87 88 views::Widget* zoom_widget_; 89 90 DISALLOW_COPY_AND_ASSIGN(PartialMagnificationController); 91 }; 92 93 } // namespace ash 94 95 #endif // ASH_MAGNIFIER_PARTIAL_MAGNIFICATION_CONTROLLER_H_ 96