前言

自定義控件的時(shí)候，經(jīng)常會(huì)不僅在代碼中創(chuàng)建該控件，現(xiàn)在還越來(lái)越多的在Storyboard和XIB中直接創(chuàng)建，如果僅僅是為了修改某些屬性，或者在運(yùn)行過(guò)程中不需要修改的東西，我們就不需要每次都拖線，修改屬性。

示例1：按鈕的圓角、邊框

在可視化創(chuàng)建UI的過(guò)程中，總有需要設(shè)置按鈕的圓角、邊框的情況，在最開(kāi)始，作者都是使用的 1.拖線，2.修改屬性。此類方法。
后來(lái)發(fā)現(xiàn),可以直接在User Defined Runtime Attributes中添加運(yùn)行時(shí)修改的屬性，于是，再也不需要為僅僅做展示用的一些控件拖線來(lái)修改layer了。

注：上圖中的borderColorFromUIColor和shadowColorFromUIColor用于設(shè)置邊框顏色和陰影顏色，直接設(shè)置是UIColor，但對(duì)應(yīng)的屬性是CGColor，所以需要為CALayer添加分類：

#import <QuartzCore/QuartzCore.h>

#import <UIKit/UIKit.h>
@interface CALayer (Addition)

@property(nonatomic, strong) UIColor *borderColorFromUIColor;
@property(nonatomic, strong) UIColor *shadowColorFromUIColor;
- (void)setBorderColorFromUIColor:(UIColor *)color;
- (void)setShadowColorFromUIColor:(UIColor *)color;
@end

#import "CALayer+Addition.h"
#import <objc/runtime.h>

@implementation CALayer (Addition)
//static const void *borderColorFromUIColorKey = &borderColorFromUIColorKey;

//@dynamic borderColorFromUIColor;


- (UIColor *)borderColorFromUIColor {
    return objc_getAssociatedObject(self, @selector(borderColorFromUIColor));
}

-(void)setBorderColorFromUIColor:(UIColor *)color

{
    objc_setAssociatedObject(self, @selector(borderColorFromUIColor), color, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    [self setBorderColorFromUI:self.borderColorFromUIColor];
}

- (void)setBorderColorFromUI:(UIColor *)color

{
    self.borderColor = color.CGColor;
    
}
- (UIColor *)shadowColorFromUIColor {
    return objc_getAssociatedObject(self, @selector(shadowColorFromUIColor));
}

-(void)setShadowColorFromUIColor:(UIColor *)color

{
    objc_setAssociatedObject(self, @selector(shadowColorFromUIColor), color, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    [self setShadowColorFromUI:self.borderColorFromUIColor];
}

- (void)setShadowColorFromUI:(UIColor *)color

{
    self.shadowColor = color.CGColor;
}
@end

但是后來(lái)發(fā)現(xiàn)，每次都為了添加圓角，復(fù)制一大堆Key Path：

• layer.cornerRadius
• layer.borderWidth
• layer.borderColorFromUIColor
• layer.masksToBounds
  然后修改值，不僅手酸，還不能直接X(jué)IB文件中看到效果，必須運(yùn)行起來(lái)查看。
  于是就找到了新的方法：IB_DESIGNABLE / IBInspectable，不過(guò)目前只能用于UIView的子類
  具體方法如下：

import UIKit
//@IBDesignable告訴編譯器，此類可以被nib識(shí)別使用
@IBDesignable class BoardButton: UIButton {

    //@IBInspectable告訴編譯器,這個(gè)屬性是可視化的
    @IBInspectable var borderWidth : CGFloat = 0{
        didSet{
            layer.borderWidth = borderWidth
        }
    }
    
    @IBInspectable var borderColor : UIColor = UIColor.clear{
        didSet{
            layer.borderColor = borderColor.cgColor
        }
    }
    
    @IBInspectable var cornerRadius : CGFloat = 0{
        didSet{
            layer.cornerRadius = cornerRadius
        }
    }
    
    @IBInspectable var masksToBounds : Bool = false{
        didSet{
            layer.masksToBounds = masksToBounds
        }
    }

}

這樣直接在XIB文件中添加一個(gè)UIButton，并設(shè)置好約束，修改類別為BoardButton，就可以看到具體的屬性了。

這樣是不是很輕松呢，以后可以直接把你寫(xiě)好的按鈕拿到新的項(xiàng)目中，就可以直接設(shè)置layer的一些屬性了，你也可以添加陰影，方法是一樣的。

示例2：點(diǎn)擊上傳圖片或照片的view

做好了上面的按鈕后，正好需要提取一個(gè)上傳照片的工具類，我就準(zhǔn)備把它集成到一個(gè)view上面去，先說(shuō)說(shuō)這個(gè)view的功能：

• 可以預(yù)先設(shè)置，view的背景顏色
• 可以預(yù)先設(shè)置，點(diǎn)擊view是直接選擇照片還是直接拍照，或者彈出提示框，手動(dòng)選擇。（其實(shí)這個(gè)設(shè)置是為了適配公司項(xiàng)目的要求，默認(rèn)的是手動(dòng)選擇）
• 可以預(yù)先設(shè)置，是否需要?jiǎng)h除按鈕（大小及圖片），默認(rèn)需要設(shè)置。點(diǎn)擊刪除按鈕，通過(guò)閉包傳出，外面持有這個(gè)view的父控件或者控制器做處理，如果沒(méi)有刪除按鈕，再次點(diǎn)擊圖片，彈出提示框，重新選擇圖片或刪除。
  具體實(shí)現(xiàn)代碼如下：文件名AddImageView.swift

import UIKit
import SVProgressHUD
@IBDesignable class AddImageView: UIView ,UIActionSheetDelegate{
    // 成功選擇了一張圖片
    var didSelectedPicture : ((_ imageUrl: String) -> ())?
    // 選擇圖片失敗
    var failedSelectedPicture : ((_ info: String) -> ())?
    // 選擇了刪除圖片
    var didClickDeletePicture : (() -> ())?
    // 彈出視圖的viewController
    var presentViewController : UIViewController? = {
        return UIApplication.shared.keyWindow?.rootViewController
    }()
    //刪除照片的模式,false:通過(guò)點(diǎn)擊圖片刪除,true:通過(guò)刪除按鈕刪除
    @IBInspectable var bgColor : UIColor = UIColor.white {
        didSet {
            backgroundColor = bgColor
        }
    }
    //選擇相冊(cè)的模式，如果都選擇FALSE，則都改為TRUE
    @IBInspectable var fromPhoto : Bool = true {
        didSet {
        }
    }
    //選擇拍照的模式，如果都選擇FALSE，則都改為TRUE
    @IBInspectable var fromCamera : Bool = true {
        didSet {
        }
    }
    //刪除照片的模式,false:通過(guò)點(diǎn)擊圖片刪除,true:通過(guò)刪除按鈕刪除
    @IBInspectable var delbtnBtntype : Bool = false {
        didSet {
        }
    }
    //刪除按鈕圖片
    @IBInspectable var delbtnImage : UIImage? {
        didSet {
        }
    }
    //刪除按鈕size
    @IBInspectable var delbtnSize : CGSize = CGSize(width: 10, height:10) {
        didSet {
        }
    }
    // 默認(rèn)背景圖片
    @IBInspectable var defaultImage : UIImage?{
        didSet{
            imageView.image = defaultImage
        }
    }
    //默認(rèn)背景圖片的size
    @IBInspectable var defaultImageSize : CGSize = CGSize(width: 10, height:10) {
        didSet {
        }
    }
    //選中的照片
    var selectedImage : UIImage? {
        didSet{
            imageView.contentMode = .scaleAspectFit
            imageView.image = selectedImage
        }
    }
    // 刪除按鈕
    var deleteButton : UIButton
    // 整個(gè)ImageView
    var imageView : UIImageView
    // 圖片選擇器界面
    var imagePickerController: UIImagePickerController?
    // 代碼創(chuàng)建時(shí)
    override init(frame: CGRect) {
        imageView = UIImageView()
        deleteButton = UIButton()
        super.init(frame: frame)
        addSubview(imageView)
        addSubview(deleteButton)
        addTapOnImageView()
    }
    // XIB創(chuàng)建時(shí)
    required init?(coder aDecoder: NSCoder) {
        imageView = UIImageView()
        deleteButton = UIButton()
        super.init(coder: aDecoder)
        addSubview(imageView)
        addSubview(deleteButton)
        addTapOnImageView()
    }
    func addTapOnImageView() {
        let tap = UITapGestureRecognizer(target: self, action: #selector(tapImageView))
        imageView.isUserInteractionEnabled = true
        imageView.addGestureRecognizer(tap)
    }
    @objc private func tapImageView() {
        if fromPhoto == true && fromCamera == false {
            if selectedImage == nil {//初次選擇照片
                addPhonto(type:.photoLibrary)
            }else{
                let alert = UIActionSheet.init(title: nil, delegate: self, cancelButtonTitle: "取消", destructiveButtonTitle: nil, otherButtonTitles: "重新選擇","刪除")
                alert.tag = 103
                if presentViewController != nil {
                    alert.show(in: (presentViewController?.view)!)
                }
            }
        }else if fromPhoto == false && fromCamera == true {
            if selectedImage == nil {//初次選擇照片
                addPhonto(type:.camera)
            }else{
                let alert = UIActionSheet.init(title: nil, delegate: self, cancelButtonTitle: "取消", destructiveButtonTitle: nil, otherButtonTitles: "重新拍照","刪除")
                alert.tag = 102
                if presentViewController != nil {
                    alert.show(in: (presentViewController?.view)!)
                }
            }
        }else{
            let alert = UIActionSheet.init(title: nil, delegate: self, cancelButtonTitle: "取消", destructiveButtonTitle: nil, otherButtonTitles: "相冊(cè)","相機(jī)")
            alert.tag = 101
            if presentViewController != nil {
                alert.show(in: (presentViewController?.view)!)
            }
        }
    }
    func actionSheet(_ actionSheet: UIActionSheet, clickedButtonAt buttonIndex: Int) {
        if actionSheet.tag == 101 {
            switch buttonIndex {
            case 1:
                addPhonto(type:.photoLibrary)
            case 2:
                addPhonto(type:.camera)
            default: break
            }
        }else if actionSheet.tag == 102 {
            switch buttonIndex {
            case 1:
                addPhonto(type:.camera)
            case 2:
                deletePhoto()
            default: break
            }
        }else if actionSheet.tag == 103 {
            switch buttonIndex {
            case 1:
                addPhonto(type:.photoLibrary)
            case 2:
                 deletePhoto()
            default: break
            }
        }
    }
    func layoutImageViewAndButton() {
        var width_background : CGFloat = 0.0
        var height_background : CGFloat = 0.0
        var y_background : CGFloat = 0.0
        if delbtnBtntype == false{//如果是點(diǎn)擊圖片的方式刪除圖片,沒(méi)有刪除按鈕
            width_background = width
            height_background = height
            deleteButton.removeFromSuperview()
        }else{//如果是點(diǎn)擊刪除按鈕的方式刪除圖片
            y_background = delbtnSize.height / CGFloat(2.0)
            width_background = width - delbtnSize.width / 2.0
            height_background = height - delbtnSize.height / 2.0
            deleteButton.frame = CGRect(origin: CGPoint(x: width_background, y: 0), size: delbtnSize)
            deleteButton.addTarget(self, action: #selector(didClickDeleteBtn), for: .touchUpInside)
            deleteButton.setBackgroundImage(delbtnImage, for: .normal)
            backgroundColor = UIColor.white
            let backView = UIView.init(frame: CGRect(x: 0.0, y: y_background, width: width_background, height: height_background))
            backView.backgroundColor = bgColor
            insertSubview(backView, at: 0)
        }
        imageView.frame = CGRect(x: 0.0, y: y_background, width: width_background, height: height_background)
        if selectedImage == nil{//沒(méi)有選中的圖片了，展示默認(rèn)圖
            if defaultImage != nil {//有默認(rèn)圖
                if (defaultImageSize.width) <= width_background && (defaultImageSize.height) <= height_background {//設(shè)置的默認(rèn)圖的size比自身size小
                    UIGraphicsBeginImageContextWithOptions(defaultImageSize,false,UIScreen.main.scale)
                    defaultImage?.draw(in: CGRect(x:0, y:0, width:defaultImageSize.width, height:defaultImageSize.height))
                    let reSizeImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()!
                    UIGraphicsEndImageContext();
                    imageView.contentMode = .center
                    imageView.image = reSizeImage
                }else{
                    imageView.contentMode = .scaleAspectFit
                    imageView.image = defaultImage
                }
            }
        }else{//有選中的圖片了，不展示默認(rèn)圖
            imageView.contentMode = .scaleAspectFit
        }
    }
    @objc private func didClickDeleteBtn() {
        deletePhoto()
    }
    override func layoutSubviews() {
        super.layoutSubviews()
        layoutImageViewAndButton()
    }
}
extension AddImageView {
    func deletePhoto() {
        selectedImage = nil
        layoutImageViewAndButton()
        if didClickDeletePicture != nil {
            didClickDeletePicture!()
        }
    }
    func upLoadSeletecdImage(image: UIImage) {
        // 上傳圖片的方法，可以設(shè)置到此view中
        NetworkTool.sharedInstance.uploadImage(image: selectedImage!, progressing:{(progress:Double)in
            SVProgressHUD.showProgress(Float(progress))
        },success: { (result, isSuccess) in
            SVProgressHUD.dismiss()
            if isSuccess{
                if let returnUrl = result["body"]["picurl"]["returnUrl"].string {
                    if self.didSelectedPicture != nil{
                        self.didSelectedPicture!(returnUrl)
                    }
                }else{
                    if self.failedSelectedPicture != nil{
                        self.failedSelectedPicture!("上傳圖片失敗")
                    }
                }
            }
            
        }) { (error) in
            SVProgressHUD.dismiss()
        }
    }
}
extension AddImageView: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    //MARK:- present選擇照片
    func addPhonto(type :UIImagePickerControllerSourceType) {
        if UIImagePickerController.isSourceTypeAvailable(type) == false {
            if failedSelectedPicture != nil {
                failedSelectedPicture!("該設(shè)備不支持相機(jī)")
            }
            return
        }
        imagePickerController = UIImagePickerController()
        imagePickerController?.delegate = self
        imagePickerController?.sourceType = type
        imagePickerController?.allowsEditing = true
        // 打開(kāi)圖片選擇器
        presentViewController?.present(imagePickerController!, animated: true, completion: nil)
    }
    //MARK: 返回照片信息
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
        presentViewController?.dismiss(animated: true, completion: nil)
        selectedImage = info[UIImagePickerControllerEditedImage] as? UIImage
        if selectedImage != nil{
            upLoadSeletecdImage(image: selectedImage!)
        }
        if failedSelectedPicture != nil && selectedImage == nil {
            failedSelectedPicture!("未獲取到圖片信息")
        }
    }
}

AddimageView屬性

具體內(nèi)容稍后會(huì)放在GitHub并不斷優(yōu)化，歡迎下載嘗試。