2.UIImageView

来源：互联网发布：哥哥帅体验知乎编辑：程序博客网时间：2024/06/05 03:58

UIImageView

UIImageView用于显示图片,我们将学习UIImageView的常用方法.

1. 添加一张图片到项目中

添加图片

为什么使用这张图片呢? 因为本人是射手座!

2. 创建UIImageView

import UIKitclass ViewController: UIViewController {    override func viewDidLoad() {        super.viewDidLoad()        let imageView = UIImageView(image: UIImage(named: "image"))        self.view.addSubview(imageView)    }    override func didReceiveMemoryWarning() {        super.didReceiveMemoryWarning()    }}

现在我们看看效果:

UIImageView创建

3. 加载网络图片

加载网络图片的需求肯定是有的, 对于这种情况, 要善于使用第三方框架,这里我们使用AlamofireImage.

在项目目录下新建一个Podfile文件, 添加如下内容:

source 'https://github.com/CocoaPods/Specs.git'platform :ios, '8.0'use_frameworks!pod 'AlamofireImage', '~> 2.0'

然后在命令行中进入Podfile文件所在目录,执行下面命令:

pod install

然后添加代码:

let imageView = UIImageView(frame: CGRect(x: 100, y: 20, width: 200, height: 200))let URL = NSURL(string: "http://www.qq1234.org/uploads/allimg/150108/1153403130-5.jpg")!let placeholderImage = UIImage(named: "image")!imageView.af_setImageWithURL(URL, placeholderImage: placeholderImage)self.view.addSubview(imageView)

实际效果:

网络图片

需要注意的是: iOS9之后, 默认http是访问不到的,我们简单的设置一下:

在info.plist文件中, 添加NSAppTransportSecurity, 类型Dictionary, 然后在该字典中添加NSAllowsArbitraryLoads, Boolean类型, 值设置为YES

Http设置

4. 完整代码

import UIKitimport AlamofireImageclass ViewController: UIViewController {    override func viewDidLoad() {        super.viewDidLoad()//        let imageView = UIImageView(image: UIImage(named: "image"))//        self.view.addSubview(imageView)        let imageView = UIImageView(frame: CGRect(x: 100, y: 20, width: 200, height: 200))        let URL = NSURL(string: "http://www.qq1234.org/uploads/allimg/150108/1153403130-5.jpg")!        let placeholderImage = UIImage(named: "image")!        imageView.af_setImageWithURL(URL, placeholderImage: placeholderImage)        self.view.addSubview(imageView)    }    override func didReceiveMemoryWarning() {        super.didReceiveMemoryWarning()    }}

4 0