1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.camera.ui;
18 
19 import android.content.Context;
20 import android.view.GestureDetector;
21 import android.view.InputDevice;
22 import android.view.KeyEvent;
23 import android.view.MotionEvent;
24 import android.view.ScaleGestureDetector;
25 
26 import com.android.camera.debug.Log;
27 
28 // This class aggregates two gesture detectors: GestureDetector,
29 // ScaleGestureDetector.
30 public class FilmstripGestureRecognizer {
31     @SuppressWarnings("unused")
32     private static final Log.Tag TAG = new Log.Tag("FStripGestureRecog");
33 
34     public interface Listener {
onSingleTapUp(float x, float y)35         boolean onSingleTapUp(float x, float y);
onDoubleTap(float x, float y)36         boolean onDoubleTap(float x, float y);
onScroll(float x, float y, float dx, float dy)37         boolean onScroll(float x, float y, float dx, float dy);
onMouseScroll(float hscroll, float vscroll)38         boolean onMouseScroll(float hscroll, float vscroll);
onFling(float velocityX, float velocityY)39         boolean onFling(float velocityX, float velocityY);
onScaleBegin(float focusX, float focusY)40         boolean onScaleBegin(float focusX, float focusY);
onScale(float focusX, float focusY, float scale)41         boolean onScale(float focusX, float focusY, float scale);
onDown(float x, float y)42         boolean onDown(float x, float y);
onUp(float x, float y)43         boolean onUp(float x, float y);
onLongPress(float x, float y)44         void onLongPress(float x, float y);
onScaleEnd()45         void onScaleEnd();
46     }
47 
48     private final GestureDetector mGestureDetector;
49     private final ScaleGestureDetector mScaleDetector;
50     private final Listener mListener;
51 
FilmstripGestureRecognizer(Context context, Listener listener)52     public FilmstripGestureRecognizer(Context context, Listener listener) {
53         mListener = listener;
54         mGestureDetector = new GestureDetector(context, new MyGestureListener(),
55                 null, true /* ignoreMultitouch */);
56         mGestureDetector.setOnDoubleTapListener(new MyDoubleTapListener());
57         mScaleDetector = new ScaleGestureDetector(
58                 context, new MyScaleListener());
59     }
60 
onTouchEvent(MotionEvent event)61     public boolean onTouchEvent(MotionEvent event) {
62         final boolean gestureProcessed = mGestureDetector.onTouchEvent(event);
63         final boolean scaleProcessed = mScaleDetector.onTouchEvent(event);
64         if (event.getAction() == MotionEvent.ACTION_UP) {
65             mListener.onUp(event.getX(), event.getY());
66         }
67         return (gestureProcessed | scaleProcessed);
68     }
69 
onGenericMotionEvent(MotionEvent event)70     public boolean onGenericMotionEvent(MotionEvent event) {
71         if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) {
72             switch (event.getAction()) {
73                 case MotionEvent.ACTION_SCROLL: {
74                     final float hscroll = event.getAxisValue(MotionEvent.AXIS_HSCROLL);
75                     final float vscroll = -event.getAxisValue(MotionEvent.AXIS_VSCROLL);
76 
77                     if (hscroll != 0.0f || vscroll != 0.0f) {
78                         mListener.onMouseScroll(hscroll, vscroll);
79                     }
80                 }
81             }
82         }
83 
84         return true;
85     }
86 
87     private class MyGestureListener
88                 extends GestureDetector.SimpleOnGestureListener {
89         @Override
onLongPress(MotionEvent e)90         public void onLongPress(MotionEvent e) {
91             mListener.onLongPress(e.getX(), e.getY());
92         }
93 
94         @Override
onScroll( MotionEvent e1, MotionEvent e2, float dx, float dy)95         public boolean onScroll(
96                 MotionEvent e1, MotionEvent e2, float dx, float dy) {
97             return mListener.onScroll(e2.getX(), e2.getY(), dx, dy);
98         }
99 
100         @Override
onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)101         public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
102                 float velocityY) {
103             return mListener.onFling(velocityX, velocityY);
104         }
105 
106         @Override
onDown(MotionEvent e)107         public boolean onDown(MotionEvent e) {
108             mListener.onDown(e.getX(), e.getY());
109             return super.onDown(e);
110         }
111     }
112 
113     /**
114      * The listener that is used to notify when a double-tap or a confirmed
115      * single-tap occur.
116      */
117     private class MyDoubleTapListener implements GestureDetector.OnDoubleTapListener {
118 
119         @Override
onSingleTapConfirmed(MotionEvent e)120         public boolean onSingleTapConfirmed(MotionEvent e) {
121             return mListener.onSingleTapUp(e.getX(), e.getY());
122         }
123 
124         @Override
onDoubleTap(MotionEvent e)125         public boolean onDoubleTap(MotionEvent e) {
126             return mListener.onDoubleTap(e.getX(), e.getY());
127         }
128 
129         @Override
onDoubleTapEvent(MotionEvent e)130         public boolean onDoubleTapEvent(MotionEvent e) {
131             return true;
132         }
133     }
134 
135     private class MyScaleListener
136             extends ScaleGestureDetector.SimpleOnScaleGestureListener {
137         @Override
onScaleBegin(ScaleGestureDetector detector)138         public boolean onScaleBegin(ScaleGestureDetector detector) {
139             return mListener.onScaleBegin(
140                     detector.getFocusX(), detector.getFocusY());
141         }
142 
143         @Override
onScale(ScaleGestureDetector detector)144         public boolean onScale(ScaleGestureDetector detector) {
145             return mListener.onScale(detector.getFocusX(),
146                     detector.getFocusY(), detector.getScaleFactor());
147         }
148 
149         @Override
onScaleEnd(ScaleGestureDetector detector)150         public void onScaleEnd(ScaleGestureDetector detector) {
151             mListener.onScaleEnd();
152         }
153     }
154 }
155