1 #ifndef DALI_INTERNAL_ACCESSIBILITY_GESTURE_DETECTOR_H
2 #define DALI_INTERNAL_ACCESSIBILITY_GESTURE_DETECTOR_H
5 * Copyright (c) 2019 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
24 #include <dali/devel-api/adaptor-framework/accessibility-gesture-handler.h>
25 #include <dali/devel-api/adaptor-framework/accessibility-gesture-event.h>
26 #include <dali/integration-api/scene.h>
43 * Detects an accessibility pan gesture and sends it to the gesture handler.
45 class AccessibilityGestureDetector : public RefObject
52 AccessibilityGestureDetector();
57 ~AccessibilityGestureDetector() override;
60 * Set the handler to handle accessibility gestures.
61 * @param[in] handler The Accessibility gesture handler.
62 * @note Handlers should remove themselves when they are destroyed.
64 void SetGestureHandler(AccessibilityGestureHandler& handler);
66 void SendEvent(const Integration::TouchEvent& event);
68 void SendEvent(Integration::Scene& scene, const Integration::TouchEvent& event)
77 * Emits the pan gesture event (performs some smoothing operation).
78 * @param[in] state The state of the pan.
79 * @param[in] currentEvent The latest touch event.
81 void SendPan(AccessibilityGestureEvent::State state, const Integration::TouchEvent& currentEvent);
84 * Emits the pan gesture event to the gesture handler.
85 * @param[in] gesture The pan gesture event.
87 void EmitPan(const AccessibilityGestureEvent gesture);
92 * Internal state machine.
96 CLEAR, ///< No gesture detected.
97 POSSIBLE, ///< The current touch event data suggests that a gesture is possible.
98 STARTED, ///< A gesture has been detected.
99 FINISHED, ///< A previously started pan gesture has finished.
100 FAILED, ///< Current touch event data suggests a pan gesture is not possible.
103 State mState; ///< The current state of the detector.
105 Integration::Scene* mScene;
106 AccessibilityGestureHandler* mGestureHandler; ///< The pointer of accessibility gesture handler
107 bool mPanning; ///< Keep track of panning state, when panning is occuring, this is true.
109 std::vector<Integration::TouchEvent> mTouchEvents; ///< A container of all touch events after an initial down event.
111 Vector2 mPrimaryTouchDownLocation; ///< The initial touch down point.
112 Vector2 mThresholdAdjustmentPerFrame; ///< The adjustment per frame at the start of a slow pan.
113 Vector2 mPreviousPosition; ///< The previous position.
115 unsigned int mThresholdAdjustmentsRemaining; ///< No. of threshold adjustments still to apply (for a slow-pan).
116 unsigned int mThresholdTotalAdjustments; ///< The total number of adjustments required.
118 uint32_t mPrimaryTouchDownTime; ///< The initial touch down time.
119 unsigned int mMinimumTouchesRequired; ///< The minimum touches required before a pan should be emitted.
120 unsigned int mMaximumTouchesRequired; ///< The maximum touches after which a pan should not be emitted.
121 unsigned int mMinimumDistanceSquared; ///< The minimum distance squared before pan should start.
122 unsigned int mMinimumMotionEvents; ///< The minimum motion events before pan should start.
123 unsigned int mMotionEvents; ///< The motion events received so far (before pan is emitted).
126 using AccessibilityGestureDetectorPtr = Dali::IntrusivePtr<AccessibilityGestureDetector>;
128 } // namespace Adaptor
130 } // namespace Internal
134 #endif // DALI_INTERNAL_ACCESSIBILITY_GESTURE_DETECTOR_H