//
//  PageCollectionViewFlowLayout.swift
//  DNSPageView
//
//  Created by Daniels on 2018/2/24.
//  Copyright © 2018 Daniels. All rights reserved.
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included in
//  all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//  THE SOFTWARE.
//

import UIKit

/// 通过设置 offset 的值，达到初始化的 pageView 默认显示某一页的效果，默认显示第一页
public class PageCollectionViewFlowLayout: UICollectionViewFlowLayout {
    var offset: CGFloat?
    
    public override func prepare() {
        super.prepare()
        guard let offset = offset else { return }
        collectionView?.contentOffset = CGPoint(x: offset, y: 0)
    }
    
    public override var flipsHorizontallyInOppositeLayoutDirection: Bool {
        return true
    }
}