1 // Copyright 2014 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.
5 #ifndef ATHENA_WM_BEZEL_CONTROLLER_H_
6 #define ATHENA_WM_BEZEL_CONTROLLER_H_
8 #include "ui/events/event_handler.h"
24 // Responsible for detecting bezel gestures and notifying the delegate(s)
25 // subscribed to them.
26 class BezelController : public ui::EventHandler {
28 enum Bezel { BEZEL_NONE, BEZEL_LEFT, BEZEL_RIGHT, BEZEL_TOP, BEZEL_BOTTOM };
30 // Responsible for handling scroll gestures initiated from the bezel.
31 // Two touch points are need to perform the bezel scroll gesture from
32 // the left and right bezel.
33 class ScrollDelegate {
35 virtual ~ScrollDelegate() {}
37 // Beginning of a bezel scroll gesture started from the |bezel|.
38 // |delta| is the difference between the x-coordinate of the current scroll
39 // position and the bezel. It will be zero or negative for the right bezel.
40 virtual void BezelScrollBegin(Bezel bezel, float delta) = 0;
42 // End of the current bezel scroll
43 virtual void BezelScrollEnd() = 0;
45 // Update of the scroll position for the currently active bezel scroll.
46 // |delta| has the same meaning as in ScrollBegin().
47 virtual void BezelScrollUpdate(float delta) = 0;
49 // Should return false if the delegate isn't going to react to the scroll
51 virtual bool BezelCanScroll() = 0;
54 explicit BezelController(aura::Window* container);
55 virtual ~BezelController() {}
57 // Set the delegate to handle the gestures from left and right bezels.
58 // Two touch points are need to perform the bezel scroll gesture from
59 // the left and right bezel.
60 void set_left_right_delegate(ScrollDelegate* delegate) {
61 left_right_delegate_ = delegate;
67 IGNORE_CURRENT_SCROLL,
68 BEZEL_GESTURE_STARTED,
69 BEZEL_SCROLLING_ONE_FINGER,
70 BEZEL_SCROLLING_TWO_FINGERS,
73 void SetState(State state);
74 // |scroll_delta| only needs to be passed when |state| is one of the
75 // BEZEL_SROLLING states.
76 void SetState(State state, float scroll_delta);
78 // ui::EventHandler overrides
79 virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
81 aura::Window* container_;
85 // The bezel where the currently active scroll was started.
88 // The target of the bezel scroll gesture. Used to filter out other gestures
89 // when the bezel scroll is in progress.
90 ui::EventTarget* scroll_target_;
92 // Responsible for handling gestures started from the left and right bezels.
94 ScrollDelegate* left_right_delegate_;
96 DISALLOW_COPY_AND_ASSIGN(BezelController);
101 #endif // ATHENA_WM_BEZEL_CONTROLLER_H_