捏缩放并滚动imageView（缩放时摇动）

Question

我实现了一个可缩放和可滚动的GestrueDetector。我不想要自定义imageView或自定义视图，仅希望通过它实现它。

当我们使用此缩放功能时，它会导致图像滚动或晃动，您可以调用它！

我不能使用customView，因为我使用的是github libphotoeditor，它给了我一个imageView类型的sourceView

要在以下类别下使用：myView.setOnTouchListener(AppScaleGestureDetector(this))

class AppScaleGestureDetector(c: Context?) :
OnTouchListener, OnScaleGestureListener, GestureDetector.OnGestureListener, GestureDetector.OnDoubleTapListener {

private var view: View? = null
private val gesture = GestureDetector(c, this)
private val gestureScale: ScaleGestureDetector = ScaleGestureDetector(c, this)
private var scaleFactor = 1f
private var inScale = false
private var isZoomed: Boolean = false

override fun onTouch(view: View?, event: MotionEvent?): Boolean {
    this.view = view
    gesture.onTouchEvent(event)
    gestureScale.onTouchEvent(event)
    return true
}

override fun onScale(p0: ScaleGestureDetector?): Boolean {
    if(p0 != null) {
        scaleFactor *= p0.scaleFactor
        scaleFactor = if (scaleFactor < 1f) 1f else scaleFactor
        isZoomed = scaleFactor > 1f
        scaleFactor = (scaleFactor * 100).toInt().toFloat() / 100
        view?.scaleX = scaleFactor
        view?.scaleY = scaleFactor
        onScroll(null, null, 0f, 0f)
        return true
    }
    return false
}


override fun onScaleBegin(detector: ScaleGestureDetector?): Boolean {
    inScale = true
    return true
}

override fun onScaleEnd(detector: ScaleGestureDetector?) {
    inScale = false
    onScroll(null, null, 0f, 0f)
}

override fun onShowPress(p0: MotionEvent?) {
}

override fun onSingleTapUp(p0: MotionEvent?): Boolean {
    return true
}

override fun onDown(p0: MotionEvent?): Boolean {
    return true
}

override fun onFling(p0: MotionEvent?, p1: MotionEvent?, p2: Float, p3: Float): Boolean {
    return true
}

override fun onScroll(event1: MotionEvent?, event2: MotionEvent?, x: Float, y: Float): Boolean {
    var newX = view!!.x
    var newY = view!!.y
    if (!inScale) {
        newX -= x
        newY -= y
    }
    val wm = view!!.context
        .getSystemService(Context.WINDOW_SERVICE) as WindowManager
    val d = wm.defaultDisplay
    val p = Point()
    d.getSize(p)

    if (newX > (view!!.width * scaleFactor - p.x) / 2) {
        newX = (view!!.width * scaleFactor - p.x) / 2
    } else if (newX < -((view!!.width * scaleFactor - p.x) / 2)) {
        newX = -((view!!.width * scaleFactor - p.x) / 2)
    }

    if (newY > (view!!.height * scaleFactor - p.y) / 2) {
        newY = (view!!.height * scaleFactor - p.y) / 2
    } else if (newY < -((view!!.height * scaleFactor - p.y) / 2)) {
        newY = -((view!!.height * scaleFactor - p.y) / 2)
    }

    if(!inScale) {
        view!!.x = newX
        view!!.y = newY
    }


    return true
}

override fun onLongPress(p0: MotionEvent?) {
}

override fun onDoubleTap(p0: MotionEvent?): Boolean {
    if (isZoomed) {
        view?.scaleY = 1.0f
        view?.scaleX = 1.0f
        view?.x = 0f
        view?.y = 0f
        isZoomed = false
    }else {
        view?.scaleY = 5.0f
        view?.scaleX = 5.0f
        view?.x = 0f
        view?.y = 0f
        isZoomed = true
    }

    return true
}

override fun onDoubleTapEvent(p0: MotionEvent?): Boolean {
    return true
}

override fun onSingleTapConfirmed(p0: MotionEvent?): Boolean {
    return true
}

}