CameraFragment with some gestures and animations

CameraFragment.kt

package eram.ir.camerapager

import android.os.Bundle
import android.support.v4.app.Fragment
import kotlinx.android.synthetic.main.camera_fragment.*
import android.view.*
import android.widget.FrameLayout
import android.animation.ValueAnimator
import android.content.res.Resources
import android.view.animation.DecelerateInterpolator
import android.util.DisplayMetrics
import android.util.TypedValue
import com.otaliastudios.cameraview.Facing


class CameraFragment : Fragment() {


    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        return LayoutInflater.from(context).inflate(R.layout.camera_fragment, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)


        val viewPager = view.parent as CViewPager
        viewPager.setOnExitListener(object : CViewPager.ExitListener {
            override fun onExit() {

                (viewPager).enabledScroll = true
                viewPager.setCurrentItem(1, true)

                val margin = dpToPx(100f).toInt()
                val parentWidth = parent.measuredWidth - margin
                val widthAnimator = ValueAnimator.ofInt(cv.width, parentWidth)
                widthAnimator.duration = 700
                widthAnimator.interpolator = DecelerateInterpolator()
                widthAnimator.addUpdateListener { animation ->
                    cv.layoutParams.width = animation.animatedValue as Int
                    cv.layoutParams.height = FrameLayout.LayoutParams.WRAP_CONTENT
                    cv.requestLayout()
                }

                val scaleAnimator = ValueAnimator.ofFloat(viewPager.scaleX, 1f)
                scaleAnimator.duration = 400
                scaleAnimator.interpolator = DecelerateInterpolator()
                scaleAnimator.addUpdateListener { animation ->
                    viewPager.scaleX = animation.animatedValue as Float
                    viewPager.scaleY = animation.animatedValue as Float
                }

                widthAnimator.start()
                scaleAnimator.start()
            }
        })
        camera.setOnTouchListener { _, event ->
            if (event.action == MotionEvent.ACTION_UP) {

                (viewPager).enabledScroll = false
                viewPager.setCurrentItem(1, true)

                val parentWidth = parent.measuredWidth
                val widthAnimator = ValueAnimator.ofInt(cv.width, parentWidth)
                widthAnimator.duration = 700
                widthAnimator.interpolator = DecelerateInterpolator()
                widthAnimator.addUpdateListener { animation ->
                    cv.layoutParams.width = animation.animatedValue as Int
                    cv.layoutParams.height = animation.animatedValue as Int
                    cv.requestLayout()
                }

                val scaleAnimator = ValueAnimator.ofFloat(viewPager.scaleX, 1.5f)
                scaleAnimator.duration = 400
                scaleAnimator.interpolator = DecelerateInterpolator()
                scaleAnimator.addUpdateListener { animation ->
                    viewPager.scaleX = animation.animatedValue as Float
                    viewPager.scaleY = animation.animatedValue as Float
                }

                widthAnimator.start()
                scaleAnimator.start()
                true
            } else
//            cv.layoutParams= FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,FrameLayout.LayoutParams.MATCH_PARENT)
                false
        }

    }

    override fun onResume() {
        super.onResume()
        camera.facing = Facing.BACK
        camera.start()
    }

    override fun onPause() {
        camera.stop()
        super.onPause()
    }

    override fun onDestroyView() {
        super.onDestroyView()
        camera.destroy()
    }

    fun dpToPx(dp: Float): Float {
        return (dp * Resources.getSystem().getDisplayMetrics().density);
    }


}