UIViewに重力を適用させる

Preview uikit075

Swift3.0

//
//  ViewController.swift
//  UIKit075
//
//  Created by Misato Morino on 2016/08/15.
//  Copyright © 2016年 Misato Morino. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    //UIDynamicAnimatorはインスタンスを保存しなければアニメーションが実行されない
    var animator : UIDynamicAnimator!

    var gravity : UIGravityBehavior!

    override func viewDidLoad() {

        super.viewDidLoad()

        self.view.backgroundColor = UIColor.cyan

        // Labelを作成.
        let myLabel: UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 40))
        myLabel.backgroundColor = UIColor.orange
        myLabel.layer.masksToBounds = true
        myLabel.layer.cornerRadius = 20.0
        myLabel.text = "Hello Swift!!"
        myLabel.textColor = UIColor.white
        myLabel.shadowColor = UIColor.gray
        myLabel.textAlignment = NSTextAlignment.center
        myLabel.layer.position = CGPoint(x: self.view.bounds.width/2,y: -200)
        self.view.addSubview(myLabel)

        // Buttonを作成.
        let myButton = UIButton(frame: CGRect(x: 0, y: 0, width: 200, height: 50))
        myButton.layer.position = CGPoint(x: self.view.frame.midX, y: 500)
        myButton.layer.masksToBounds = true
        myButton.layer.cornerRadius = 20.0
        myButton.setTitleColor(UIColor.white, for: UIControlState.normal)
        myButton.setTitleColor(UIColor.black, for: UIControlState.highlighted)
        myButton.backgroundColor = UIColor.red
        myButton.setTitle("Dropped!", for: UIControlState.normal)
        myButton.addTarget(self, action: #selector(ViewController.onClickMyButton(sender:)), for: UIControlEvents.touchUpInside)
        self.view.addSubview(myButton)

        // UIDynamiAnimatorの生成とインスタンスの保存.
        animator = UIDynamicAnimator(referenceView: self.view)

        // 重量を作り、Viewに適用させる.
        gravity = UIGravityBehavior(items: [myLabel])

        // Collisionを作成、Viewに適用させる.
        let collision = UICollisionBehavior(items: [myLabel])

        // 透明な四角形の当たり判定を作る.
        collision.addBoundary(

            // Identifier.
            withIdentifier: "barrier",

            // ベジエで四角形の図形を作る.
            for: UIBezierPath(rect:
                CGRect(x: self.view.frame.midX, y: self.view.frame.midY, width: self.view.frame.maxX, height: 10)
            )
        )

        // Collisionのアニメーションを実行.
        animator.addBehavior(collision)
    }

    func onClickMyButton(sender : UIButton){

        // Gravityのアニメーションを実行.
        animator.addBehavior(gravity)
    }
}

Swift 2.3

//
//  ViewController.swift
//  UIKit075
//
//  Created by Misato Morino on 2016/08/15.
//  Copyright © 2016年 Misato Morino. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    //UIDynamicAnimatorはインスタンスを保存しなければアニメーションが実行されない
    var animator : UIDynamicAnimator!

    var gravity : UIGravityBehavior!

    override func viewDidLoad() {

        super.viewDidLoad()

        self.view.backgroundColor = UIColor.cyanColor()

        // Labelを作成.
        let myLabel: UILabel = UILabel(frame: CGRectMake(0,0,200,40))
        myLabel.backgroundColor = UIColor.orangeColor()
        myLabel.layer.masksToBounds = true
        myLabel.layer.cornerRadius = 20.0
        myLabel.text = "Hello Swift!!"
        myLabel.textColor = UIColor.whiteColor()
        myLabel.shadowColor = UIColor.grayColor()
        myLabel.textAlignment = NSTextAlignment.Center
        myLabel.layer.position = CGPoint(x: self.view.bounds.width/2,y: -200)
        self.view.addSubview(myLabel)

        // Buttonを作成.
        let myButton = UIButton(frame: CGRectMake(0, 0, 200, 50))
        myButton.layer.position = CGPointMake(self.view.frame.midX, 500)
        myButton.layer.masksToBounds = true
        myButton.layer.cornerRadius = 20.0
        myButton.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
        myButton.setTitleColor(UIColor.blackColor(), forState: UIControlState.Highlighted)
        myButton.backgroundColor = UIColor.redColor()
        myButton.setTitle("Dropped!", forState: UIControlState.Normal)
        myButton.addTarget(self, action: #selector(ViewController.onClickMyButton(_:)), forControlEvents: UIControlEvents.TouchUpInside)
        self.view.addSubview(myButton)

        // UIDynamiAnimatorの生成とインスタンスの保存.
        animator = UIDynamicAnimator(referenceView: self.view)

        // 重量を作り、Viewに適用させる.
        gravity = UIGravityBehavior(items: [myLabel])

        // Collisionを作成、Viewに適用させる.
        let collision = UICollisionBehavior(items: [myLabel])

        // 透明な四角形の当たり判定を作る.
        collision.addBoundaryWithIdentifier(

            // Identifier.
            "barrier",

            // ベジエで四角形の図形を作る.
            forPath: UIBezierPath(rect:
                CGRectMake(self.view.frame.midX, self.view.frame.midY, self.view.frame.maxX, 10)
            )
        )

        // Collisionのアニメーションを実行.
        animator.addBehavior(collision)
    }

    func onClickMyButton(sender : UIButton){

        // Gravityのアニメーションを実行.
        animator.addBehavior(gravity)
    }
}

2.3と3.0の差分

  • addBoundaryWithIdentifier から addBoundary に変更

Reference