introducing RotationGestureDetector in the new TextViewSizeAwareTouch…

…Listener
Automattic · Nov 23, 2019 · a8e9e4f · a8e9e4f
1 parent d405539
commit a8e9e4f
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Showing 3 changed files with 93 additions and 2 deletions.
diff --git a/photoeditor/src/main/java/com/automattic/photoeditor/PhotoEditor.kt b/photoeditor/src/main/java/com/automattic/photoeditor/PhotoEditor.kt
@@ -339,7 +339,6 @@ class PhotoEditor private constructor(builder: Builder) :
                 })
             }
 
-            // TODO: will uncomment and remove TextViewSizeAwareTouchListener class accordingly in a later PR
 //            val multiTouchListenerInstance = newMultiTouchListener
 //            multiTouchListenerInstance.setOnGestureControl(object : MultiTouchListener.OnGestureControl {
 //                override fun onClick() {

diff --git a/photoeditor/src/main/java/com/automattic/photoeditor/gesture/RotationGestureDetector.kt b/photoeditor/src/main/java/com/automattic/photoeditor/gesture/RotationGestureDetector.kt
@@ -0,0 +1,80 @@
+package com.automattic.photoeditor.gesture
+
+import android.view.MotionEvent
+import android.view.View
+
+class RotationGestureDetector(private val mListener: OnRotationGestureListener?) {
+    private var fX: Float = 0.toFloat()
+    private var fY: Float = 0.toFloat()
+    private var sX: Float = 0.toFloat()
+    private var sY: Float = 0.toFloat()
+    private var ptrID1: Int = 0
+    private var ptrID2: Int = 0
+    var angle: Float = 0.toFloat()
+        private set
+
+    init {
+        ptrID1 = INVALID_POINTER_ID
+        ptrID2 = INVALID_POINTER_ID
+    }
+
+    fun onTouchEvent(view: View, event: MotionEvent): Boolean {
+        when (event.actionMasked) {
+            MotionEvent.ACTION_DOWN -> ptrID1 = event.getPointerId(event.actionIndex)
+            MotionEvent.ACTION_POINTER_DOWN -> {
+                ptrID2 = event.getPointerId(event.actionIndex)
+                sX = event.getX(event.findPointerIndex(ptrID1))
+                sY = event.getY(event.findPointerIndex(ptrID1))
+                fX = event.getX(event.findPointerIndex(ptrID2))
+                fY = event.getY(event.findPointerIndex(ptrID2))
+            }
+            MotionEvent.ACTION_MOVE -> if (ptrID1 != INVALID_POINTER_ID && ptrID2 != INVALID_POINTER_ID) {
+                val nfX: Float
+                val nfY: Float
+                val nsX: Float
+                val nsY: Float
+                nsX = event.getX(event.findPointerIndex(ptrID1))
+                nsY = event.getY(event.findPointerIndex(ptrID1))
+                nfX = event.getX(event.findPointerIndex(ptrID2))
+                nfY = event.getY(event.findPointerIndex(ptrID2))
+
+                angle = angleBetweenLines(fX, fY, sX, sY, nfX, nfY, nsX, nsY)
+                mListener?.onRotation(view, angle)
+            }
+            MotionEvent.ACTION_UP -> ptrID1 = INVALID_POINTER_ID
+            MotionEvent.ACTION_POINTER_UP -> ptrID2 = INVALID_POINTER_ID
+            MotionEvent.ACTION_CANCEL -> {
+                ptrID1 = INVALID_POINTER_ID
+                ptrID2 = INVALID_POINTER_ID
+            }
+        }
+        return true
+    }
+
+    private fun angleBetweenLines(
+        fX: Float,
+        fY: Float,
+        sX: Float,
+        sY: Float,
+        nfX: Float,
+        nfY: Float,
+        nsX: Float,
+        nsY: Float
+    ): Float {
+        val angle1 = Math.atan2((fY - sY).toDouble(), (fX - sX).toDouble()).toFloat()
+        val angle2 = Math.atan2((nfY - nsY).toDouble(), (nfX - nsX).toDouble()).toFloat()
+
+        var angle = Math.toDegrees((angle1 - angle2).toDouble()).toFloat() % 360
+        if (angle < -180f) angle += 360.0f
+        if (angle > 180f) angle -= 360.0f
+        return angle
+    }
+
+    interface OnRotationGestureListener {
+        fun onRotation(view: View, angle: Float)
+    }
+
+    companion object {
+        private val INVALID_POINTER_ID = -1
+    }
+}
diff --git a/...editor/src/main/java/com/automattic/photoeditor/gesture/TextViewSizeAwareTouchListener.kt b/...editor/src/main/java/com/automattic/photoeditor/gesture/TextViewSizeAwareTouchListener.kt
@@ -3,8 +3,10 @@ package com.automattic.photoeditor.gesture
 import android.annotation.SuppressLint
 import android.view.MotionEvent
 import android.view.View
+import com.automattic.photoeditor.gesture.RotationGestureDetector.OnRotationGestureListener
 
-class TextViewSizeAwareTouchListener(val minWidth: Int, val minHeight: Int) : View.OnTouchListener {
+class TextViewSizeAwareTouchListener(val minWidth: Int, val minHeight: Int) : View.OnTouchListener,
+    OnRotationGestureListener {
     private var originX = 0f
     private var originY = 0f
     private var secondOriginX = 0f
@@ -14,9 +16,19 @@ class TextViewSizeAwareTouchListener(val minWidth: Int, val minHeight: Int) : Vi
 
     private var originUp = false
     private var secondOriginUp = false
+    private var rotationDetector: RotationGestureDetector
+
+    init {
+        rotationDetector = RotationGestureDetector(this)
+    }
+
+    override fun onRotation(view: View, angle: Float) {
+        view.rotation = angle
+    }
 
     @SuppressLint("ClickableViewAccessibility")
     override fun onTouch(view: View, event: MotionEvent): Boolean {
+        rotationDetector.onTouchEvent(view, event)
         event.offsetLocation(event.rawX - event.x, event.rawY - event.y)
 
         when (event.actionMasked) {