using System;

using System.Collections.Generic;

using Foundation;

using UIKit;

namespace ddd

{

    public partial class ViewController : UIViewController

    {

        private List<UIImage> collectionData;

        private UICollectionView collectionView;

        private UICollectionViewFlowLayout collectionViewLayout;

        protected ViewController(IntPtr handle) : base(handle)

        {

            // Note: this .ctor should not contain any initialization logic.

        }

        public override void ViewDidLoad()

        {

            base.ViewDidLoad();

            uiConfig();

        }

        private void uiConfig()

        {

            //设置假的数据源数组

            collectionData = new List<UIImage>();

            for (int i = ; i < ; i++)

            {

                collectionData.Add(UIImage.FromFile("1.jpg"));

            }

            //初始化UICollectionView

            collectionViewLayout = new UICollectionViewFlowLayout();

            collectionViewLayout.MinimumLineSpacing = 20f;//设置行距

            collectionViewLayout.MinimumInteritemSpacing = 10f;//设置列距

            collectionViewLayout.SectionInset = new UIEdgeInsets(, , , );//设置边界

            collectionViewLayout.ItemSize = new CoreGraphics.CGSize(70f, 70f);//设置网格大小  

            collectionView = new UICollectionView(this.View.Bounds, collectionViewLayout);

            collectionView.BackgroundColor = UIColor.LightTextColor;

            collectionView.RegisterNibForCell(ImageCell.Nib, "ImageCell");

            collectionView.Source = new collectionSource(this);

            this.View.AddSubview(collectionView);

        }

        public override void DidReceiveMemoryWarning()

        {

            base.DidReceiveMemoryWarning();

            // Release any cached data, images, etc that aren't in use.

        } 

        private class collectionSource : UICollectionViewSource

        {

            ViewController owner;

            public collectionSource(ViewController owner)

            {

                this.owner = owner;

            }

            //设置网格个数

            public override nint GetItemsCount(UICollectionView collectionView, nint section)

            {

                return owner.collectionData.Count;

            }

            //设置网格中的内容

            public override UICollectionViewCell GetCell(UICollectionView collectionView, NSIndexPath indexPath)

            {

                ImageCell cell = (ImageCell)collectionView.DequeueReusableCell((NSString)ImageCell.Key, indexPath);

                cell.ImageView.Image = owner.collectionData[indexPath.Row];

                return cell;

            }

            //选中某一个网格

            public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)

            {

                UIAlertView alert = new UIAlertView();

                alert.Title = string.Format("你选择了第{0}个网格", indexPath.Row);

                alert.AddButton("确定");

                alert.Show();

            }

        }

    }

    public partial class ImageCell : UICollectionViewCell

    {

        public static readonly NSString Key = new NSString("ImageCell");

        public static readonly UINib Nib;

        static ImageCell()

        {

            Nib = UINib.FromName("ImageCell", NSBundle.MainBundle);

        }

        protected ImageCell(IntPtr handle) : base(handle)

        {

            // Note: this .ctor should not contain any initialization logic.

            this.Initialize();              //调用初始化方法

        }

        //设置属性

        public UIImageView ImageView

        {

            get;

            private set;

        }

        //初始化

        private void Initialize()

        {

            this.ImageView = new UIImageView(this.ContentView.Bounds);          //实例化对象

            this.ImageView.ContentMode = UIViewContentMode.ScaleAspectFit;      //设置显示模式

            this.ContentView.AddSubview(this.ImageView);                        //添加

        }

    }

}