swift - How do I move an object back and forth with touch in iOS -

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i need move image , forth based on user's finger. want able touch screen , image move towards touch. image should move left right not , down , add limits how far image can go towards 1 side of screen.

i know sounds lot have tried many things of have caused problems. first time able click , drag image when clicked somewhere else image appear there wouldn't move there appeared.

the second thing tried allowed me drag image when clicked out of image wouldn't move towards finger @ all. @ point i'm frustrated , appreciate help. here code.

import uikit  class viewcontroller: uiviewcontroller {      @iboutlet var person: uiimageview!       override func viewdidload() {         super.viewdidload()      }       override func touchesbegan(touches: set<uitouch>, withevent event: uievent?) {         touch in (touches ){           let location = touch.locationinview(self.view)                 if person.frame.contains(location){                 person.center = location             }         }     }       override func touchesmoved(touches: set<uitouch>, withevent event: uievent?) {         touch in (touches ){             let location = touch.locationinview(self.view)                 if person.frame.contains(location){                 person.center = location             }         }     }       override func didreceivememorywarning() {         super.didreceivememorywarning()         // dispose of resources can recreated.     }   }

i assume you're using touchesbegan(_:withevent:) , touchesmoved(_:withevent:) touch events. these methods give uitouch can convert cgpoint using locationinview(_:).

when touch begins (i.e. touchesbegan(_:withevent:)), should animate custom view cgpoint of touch. e.g.:

uiview.animatewithduration(0.3, animations: {      // adjust x, not y, restrict movement along x-axis.     // check x value of point see if reached limit.     self.squareview.frame.origin.x = point.x })

when touch moves (i.e. touchesmoved(_:withevent:)), should set custom view's location cgpoint of new touch. e.g.:

// adjust x, not y, restrict movement along x-axis. // check x value of point see if reached limit. squareview.frame.origin.x = point.x

some suggestions

  1. only use first uitouch set of touches, can rid of for-loop.
  2. the line if person.frame.contains(location){ wrong because moving person if touch within person's frame, remove , set frame's origin uitouch's point (or animate using code above).

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