CODEWITHSUNDEEP
iosswiftuigesturerecognizeruipangesturerecognizercgpoint
Eco Apps
Eco Apps

Reputation: 53

How to access the initial point of a Pan Gesture in it's .Ended state

I am trying to implement a Pan Gesture in my app where I need to access the initial point in the .Ended state.

Here is the code.

func handleTestViewTap (panRecognizer: UIPanGestureRecognizer){

    var locationOfBeganTap: CGPoint?

    if panRecognizer.state == UIGestureRecognizerState.Began {           
        locationOfBeganTap = panRecognizer.locationInView(view)
        print("locationOfBeganTap in BEGAN State -> .\(locationOfBeganTap)")

    } else if panRecognizer.state == UIGestureRecognizerState.Ended {            
        print("locationOfBeganTap -> .\(locationOfBeganTap)")
        print("locationOfBeganTap in ENDED State -> .\(locationOfBeganTap)")

    }     
}

Now, here is the output:

locationOfBeganTap in BEGAN State -> .Optional((195.5, 120.0))
locationOfBeganTap in ENDED State -> .nil

I am unable to understand why the locationOfBeganTap is nil in the .Ended state

Can someone please share the code to access locationOfBeganTap in .Ended state...

Upvotes: 0

Views: 1194

Answers (2)

Jed Fox
Jed Fox

Reputation: 3025

The way you are doing this doesn’t work. Instead, calculate it all at the end:

func handleTestViewTap (panRecognizer: UIPanGestureRecognizer){

    if panRecognizer.state == UIGestureRecognizerState.Ended {            
        print("locationOfBeganTap -> (.\(touch.locationInView(view).x - touch.translationInView(view).x), .\(touch.locationInView(view).y - touch.translationInView(view).y))")
        print("location in ENDED State -> .\(touch.locationInView(view))")
    }     
}

Upvotes: 1

rmaddy
rmaddy

Reputation: 318794

You need to move locationOfBeganTap to be an instance variable instead of a local variable.

class WhatEverClassThisIs {
    var locationOfBeganTap: CGPoint?

    // and the rest of your stuff

    func handleTestViewTap (panRecognizer: UIPanGestureRecognizer){
        if panRecognizer.state == UIGestureRecognizerState.Began {           
            locationOfBeganTap = panRecognizer.locationInView(view)
            print("locationOfBeganTap in BEGAN State -> .\(locationOfBeganTap)")
        } else if panRecognizer.state == UIGestureRecognizerState.Ended {            
            print("locationOfBeganTap -> .\(locationOfBeganTap)")
            print("locationOfBeganTap in ENDED State -> .\(locationOfBeganTap)")
        }     
    }
}

Upvotes: 0

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