自動調整ScrollView讓textField適應鍵盤高度

直接把我的code貼上來，重點是不要改變scrollView.contentSize，因為auto layout時會自動設定。

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//

//  BaseScrollViewController.swift

//  BaseSettings

//

//  Created by HarveyHu on 4/26/16.

//  Copyright © 2016 HarveyHu. All rights reserved.

//

import UIKit

import SnapKit

import RxSwift

class BaseScrollViewController: UIViewController {

    let contentView = UIView()

    let scrollView = UIScrollView()

    var originalContentInsets = UIEdgeInsetsZero

    

    override func viewDidLoad() {

        super.viewDidLoad()

        setUI()

    }

    override func viewDidAppear(animated: Bool) {

        super.viewWillAppear(animated)

        originalContentInsets = scrollView.contentInset

    }

    

    override func setUI() {

        super.setUI()

        self.scrollView.addSubview(contentView)

        self.view.addSubview(scrollView)

        

    }

    

    override func setUIConstraints() {

        super.setUIConstraints()

        

        scrollView.snp_makeConstraints { (make) in

            make.top.equalTo(self.view)

            make.bottom.equalTo(self.view)

            make.leading.equalTo(self.view)

            make.trailing.equalTo(self.view)

        }

        contentView.snp_updateConstraints { (make) in

            make.top.equalTo(self.scrollView)

            make.leading.equalTo(self.scrollView)

            make.trailing.equalTo(self.scrollView)

            make.bottom.equalTo(self.scrollView)

        }

    }

    

    // MARK: - Keyboard

    @objc override func keyboardWasShown(aNotification: NSNotification)

    {

        guard let info = aNotification.userInfo, kbSize = info[UIKeyboardFrameBeginUserInfoKey]?.CGRectValue().size else {

            return

        }

        

        let contentInsets = UIEdgeInsetsMake(originalContentInsets.top, originalContentInsets.left, kbSize.height, originalContentInsets.right)

        self.scrollView.contentInset = contentInsets

        self.scrollView.scrollIndicatorInsets = contentInsets

    }

    

    @objc override func keyboardWillBeHidden(aNotification: NSNotification)

    {

        let contentInsets = originalContentInsets

        self.scrollView.contentInset = contentInsets

        self.scrollView.scrollIndicatorInsets = contentInsets

    }

}

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要用的時候就繼承這個VC，把所有內容放到contentView上，但在contentView的constraints設定上要注意寛度可以固定，但高度不要寫死，要跟著內容高度而定。

contentView.snp_updateConstraints { (make) in

            make.width.equalTo(self.view)

            make.bottom.equalTo(self.theMostBottomView).offset(10)

        }