-
Notifications
You must be signed in to change notification settings - Fork 4.7k
/
TapGestureHandler.kt
168 lines (149 loc) · 4.74 KB
/
TapGestureHandler.kt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
package versioned.host.exp.exponent.modules.api.components.gesturehandler
import android.os.Handler
import android.os.Looper
import android.view.MotionEvent
import versioned.host.exp.exponent.modules.api.components.gesturehandler.GestureUtils.getLastPointerX
import versioned.host.exp.exponent.modules.api.components.gesturehandler.GestureUtils.getLastPointerY
import kotlin.math.abs
class TapGestureHandler : GestureHandler<TapGestureHandler>() {
private var maxDeltaX = MAX_VALUE_IGNORE
private var maxDeltaY = MAX_VALUE_IGNORE
private var maxDistSq = MAX_VALUE_IGNORE
private var maxDurationMs = DEFAULT_MAX_DURATION_MS
private var maxDelayMs = DEFAULT_MAX_DELAY_MS
private var numberOfTaps = DEFAULT_NUMBER_OF_TAPS
private var minNumberOfPointers = DEFAULT_MIN_NUMBER_OF_POINTERS
private var currentMaxNumberOfPointers = 1
private var startX = 0f
private var startY = 0f
private var offsetX = 0f
private var offsetY = 0f
private var lastX = 0f
private var lastY = 0f
private var handler: Handler? = null
private var tapsSoFar = 0
private val failDelayed = Runnable { fail() }
init {
setShouldCancelWhenOutside(true)
}
override fun resetConfig() {
super.resetConfig()
maxDeltaX = MAX_VALUE_IGNORE
maxDeltaY = MAX_VALUE_IGNORE
maxDistSq = MAX_VALUE_IGNORE
maxDurationMs = DEFAULT_MAX_DURATION_MS
maxDelayMs = DEFAULT_MAX_DELAY_MS
numberOfTaps = DEFAULT_NUMBER_OF_TAPS
minNumberOfPointers = DEFAULT_MIN_NUMBER_OF_POINTERS
}
fun setNumberOfTaps(numberOfTaps: Int) = apply {
this.numberOfTaps = numberOfTaps
}
fun setMaxDelayMs(maxDelayMs: Long) = apply {
this.maxDelayMs = maxDelayMs
}
fun setMaxDurationMs(maxDurationMs: Long) = apply {
this.maxDurationMs = maxDurationMs
}
fun setMaxDx(deltaX: Float) = apply {
maxDeltaX = deltaX
}
fun setMaxDy(deltaY: Float) = apply {
maxDeltaY = deltaY
}
fun setMaxDist(maxDist: Float) = apply {
maxDistSq = maxDist * maxDist
}
fun setMinNumberOfPointers(minNumberOfPointers: Int) = apply {
this.minNumberOfPointers = minNumberOfPointers
}
private fun startTap() {
if (handler == null) {
handler = Handler(Looper.getMainLooper()) // TODO: lazy init (handle else branch correctly)
} else {
handler!!.removeCallbacksAndMessages(null)
}
handler!!.postDelayed(failDelayed, maxDurationMs)
}
private fun endTap() {
if (handler == null) {
handler = Handler(Looper.getMainLooper())
} else {
handler!!.removeCallbacksAndMessages(null)
}
if (++tapsSoFar == numberOfTaps && currentMaxNumberOfPointers >= minNumberOfPointers) {
activate()
} else {
handler!!.postDelayed(failDelayed, maxDelayMs)
}
}
private fun shouldFail(): Boolean {
val dx = lastX - startX + offsetX
if (maxDeltaX != MAX_VALUE_IGNORE && abs(dx) > maxDeltaX) {
return true
}
val dy = lastY - startY + offsetY
if (maxDeltaY != MAX_VALUE_IGNORE && abs(dy) > maxDeltaY) {
return true
}
val dist = dy * dy + dx * dx
return maxDistSq != MAX_VALUE_IGNORE && dist > maxDistSq
}
override fun onHandle(event: MotionEvent) {
val state = state
val action = event.actionMasked
if (state == STATE_UNDETERMINED) {
offsetX = 0f
offsetY = 0f
startX = event.rawX
startY = event.rawY
}
if (action == MotionEvent.ACTION_POINTER_UP || action == MotionEvent.ACTION_POINTER_DOWN) {
offsetX += lastX - startX
offsetY += lastY - startY
lastX = getLastPointerX(event, true)
lastY = getLastPointerY(event, true)
startX = lastX
startY = lastY
} else {
lastX = getLastPointerX(event, true)
lastY = getLastPointerY(event, true)
}
if (currentMaxNumberOfPointers < event.pointerCount) {
currentMaxNumberOfPointers = event.pointerCount
}
if (shouldFail()) {
fail()
} else if (state == STATE_UNDETERMINED) {
if (action == MotionEvent.ACTION_DOWN) {
begin()
}
startTap()
} else if (state == STATE_BEGAN) {
if (action == MotionEvent.ACTION_UP) {
endTap()
} else if (action == MotionEvent.ACTION_DOWN) {
startTap()
}
}
}
override fun activate(force: Boolean) {
super.activate(force)
end()
}
override fun onCancel() {
handler?.removeCallbacksAndMessages(null)
}
override fun onReset() {
tapsSoFar = 0
currentMaxNumberOfPointers = 0
handler?.removeCallbacksAndMessages(null)
}
companion object {
private const val MAX_VALUE_IGNORE = Float.MIN_VALUE
private const val DEFAULT_MAX_DURATION_MS: Long = 500
private const val DEFAULT_MAX_DELAY_MS: Long = 200
private const val DEFAULT_NUMBER_OF_TAPS = 1
private const val DEFAULT_MIN_NUMBER_OF_POINTERS = 1
}
}