iOS项目之Swift新闻App(二)—网络数据请求和添加TableHeader

1.通过对知乎日报头条的url进行Json解析，并使用代理将网络请求之后的数据传回到ViewController当中。在这里利用了Swift中使用很多Alamofire网络库，可以直接在Cocoapod中进行安装下载。在该工程项目下建一个Podfile文件，里面添加如下所示命令。

platform :ios,'8.0'

use_frameworks!

pod 'Alamofire', '~>3.0'

    func alamofireRequest(url: String){
        var model: NewsCellModel?
        Alamofire.request(.GET, url, parameters: ["foo": "bar"])
            .responseJSON { response in
                if let JSON = response.result.value {
                    if let json = JSON.objectForKey("stories"){
                        for var i = 0; i<json.count; i = i + 1{
                            let str1 = json[i].objectForKey("id")as! Int
                            //注意images格式，字符串数组
                            let str2 = json[i].objectForKey("images")![0]as! String
                            let str3 = json[i].objectForKey("title")as! String
//                            print(str1)
//                            print(str2)
//                            print(str3)
                            model = NewsCellModel(id: str1, newsImageName: str2, newsTitle: str3)
                            self.item.append(model!)
                        }

                    }
                    if let json = JSON.objectForKey("top_stories"){
                        for var i = 0; i<json.count; i = i + 1{
                            let str1 = json[i].objectForKey("id")as! Int
                            //注意images格式，字符串数组
                            let str2 = json[i].objectForKey("image")as! String
                            let str3 = json[i].objectForKey("title")as! String
//                                                        print(str1)
//                                                        print(str2)
//                                                        print(str3)
                            model = NewsCellModel(id: str1, newsImageName: str2, newsTitle: str3)
                            self.item.append(model!)
                        }
                        
                    }
                    //调用代理方法
                    self.delegate?.transforValue(self.item)
                }
        }
    }

2.添加头条新闻

在TableView视图上面有一个TableHeader视图，可以将头条新闻展示在TableHeader位置。

    /**
     Description:加载TableHeader视图
     */
    func loadHeaderView(){
        headerView = UIView(frame: CGRectMake(0,0,width,height/3))
        self.tableView.tableHeaderView = headerView
        
        scrollView = UIScrollView(frame: CGRectMake(0,0,width,height/3))
        //        scrollView.backgroundColor = UIColor.redColor()
        //一定要加上scrollView的代理，不然不能进行回调
        scrollView.delegate = self
        scrollView.contentSize = CGSize(width: width*7, height: height/3)
        //按页移动
        scrollView.pagingEnabled = true
        scrollView.bounces = true
        //不显示水平移动的标记
        scrollView.showsHorizontalScrollIndicator = false
        headerView.addSubview(scrollView)
        //button的width要注意width*7
        button = UIButton(frame: CGRectMake(0,0,width*7,height/3))
        button.addTarget(self, action: "jumpNext", forControlEvents: UIControlEvents.TouchUpInside)
        scrollView.addSubview(button)
        
        pageControl = UIPageControl(frame: CGRectMake(width/3,height/3.5,width/2,23))
        pageControl.numberOfPages = 5
        pageControl.pageIndicatorTintColor = UIColor.yellowColor()
        pageControl.currentPageIndicatorTintColor = UIColor.redColor()
        headerView.addSubview(pageControl)
        
        
        for i in 1...self.items2.count{
            let model = self.items2[i - 1]
            let imageView = UIImageView(image: UIImage(data: NSData(contentsOfURL: NSURL(string: model.newsImageName)!)!))
            imageView.frame = CGRectMake(width*CGFloat(i), 0, width, height/3)
            scrollView.addSubview(imageView)
            
            let label = UILabel(frame: CGRectMake(100 + CGFloat(i) * width,100,width/2,height/9))
            label.text = model.newsTitle
            label.textColor = UIColor.whiteColor()
            label.shadowColor = UIColor.blackColor()
            label.numberOfLines = 3
            scrollView.addSubview(label)
        }
        //添加第一页和最后一页
        let imageView1 = UIImageView(image: UIImage(data: NSData(contentsOfURL: NSURL(string: self.items2.last!.newsImageName)!)!))
        let label1 = UILabel(frame: CGRectMake(100 + CGFloat(0) * width,100,width/2,height/9))
        label1.text = self.items2[4].newsTitle
        label1.textColor = UIColor.whiteColor()
        label1.shadowColor = UIColor.blackColor()
        label1.numberOfLines = 3
        imageView1.frame = CGRectMake(width*CGFloat(0), 0, width, height/3)
        
        let imageView2 = UIImageView(image: UIImage(data: NSData(contentsOfURL: NSURL(string: self.items2.first!.newsImageName)!)!))
        let label2 = UILabel(frame: CGRectMake(100 + CGFloat(6) * width,100,width/2,height/9))
        label2.text = self.items2[0].newsTitle
        label2.textColor = UIColor.whiteColor()
        label2.shadowColor = UIColor.blackColor()
        label2.numberOfLines = 3
        imageView2.frame = CGRectMake(width*CGFloat(6), 0, width, height/3)
        
        scrollView.addSubview(imageView1)
        scrollView.addSubview(label1)
        scrollView.addSubview(imageView2)
        scrollView.addSubview(label2)
        
    }

3.具体代码请见我的Github ，欢迎star~