├── .gitignore
├── DownloaderAsyncTask.cs
├── ExtensionMethods.cs
├── Hashset.cs
├── LRUCache.cs
├── MonoDroid.UrlImageViewHelper.csproj
├── README.md
├── SoftReference.cs
├── SoftReferenceHashTable.cs
├── UrlImageCache.cs
├── UrlImageViewCallback.cs
└── UrlImageViewHelper.cs


/.gitignore:
--------------------------------------------------------------------------------
1 | # Build Folders (you can keep bin if you'd like, to store dlls and pdbs)
2 | bin
3 | obj
4 | 
5 | # mstest test results
6 | TestResults


--------------------------------------------------------------------------------
/DownloaderAsyncTask.cs:
--------------------------------------------------------------------------------
 1 | 
 2 | using System;
 3 | using System.Collections.Generic;
 4 | using System.Linq;
 5 | using System.Net;
 6 | using System.Text;
 7 | 
 8 | using Android.App;
 9 | using Android.Content;
10 | using Android.Graphics.Drawables;
11 | using Android.Net.Http;
12 | using Android.OS;
13 | using Android.Runtime;
14 | using Android.Views;
15 | using Android.Widget;
16 | 
17 | namespace UrlImageViewHelper
18 | {
19 | 	public class AnonymousAsyncTask<TParam, TProgress, TResult> : AsyncTask<TParam, TProgress, TResult>
20 | 	{
21 | 		public AnonymousAsyncTask(Func<TParam[], TResult> runInBackgroundFunc, Action<TResult> postExecuteAction)
22 | 		{
23 | 			this.RunInBackgroundFunc = runInBackgroundFunc;
24 | 			this.PostExecuteAction = postExecuteAction;
25 | 		}
26 | 
27 | 		public Func<TParam[], TResult> RunInBackgroundFunc;
28 | 		public Action<TResult> PostExecuteAction;
29 | 
30 | 		protected override TResult RunInBackground (params TParam[] @params)
31 | 		{
32 | 			return this.RunInBackgroundFunc(@params);
33 | 		}
34 | 
35 | 		protected override Java.Lang.Object DoInBackground (params Java.Lang.Object[] native_parms)
36 | 		{
37 | 			return base.DoInBackground (native_parms);
38 | 		}
39 | 
40 | 		protected override void OnPostExecute (TResult result)
41 | 		{
42 | 			this.PostExecuteAction(result);
43 | 		}
44 | 	}
45 | }
46 | 
47 | 


--------------------------------------------------------------------------------
/ExtensionMethods.cs:
--------------------------------------------------------------------------------
 1 | 
 2 | using System;
 3 | using System.Collections.Generic;
 4 | using System.Linq;
 5 | using System.Text;
 6 | 
 7 | using Android.App;
 8 | using Android.Content;
 9 | using Android.Graphics.Drawables;
10 | using Android.OS;
11 | using Android.Runtime;
12 | using Android.Views;
13 | using Android.Widget;
14 | 
15 | namespace UrlImageViewHelper
16 | {
17 | 	public static class ExtensionMethods
18 | 	{
19 | 		public static void SetUrlDrawable(this ImageView imageView, string url, int defaultResource)
20 | 		{
21 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultResource);
22 | 		}
23 | 
24 | 		public static void SetUrlDrawable(this ImageView imageView, string url)
25 | 		{
26 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url);
27 | 		}
28 | 
29 | 		public static void SetUrlDrawable(this ImageView imageView, string url, Drawable defaultDrawable)
30 | 		{
31 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultDrawable);
32 | 		}
33 | 
34 | 		public static void SetUrlDrawable(this ImageView imageView, string url, int defaultResource, long cacheDurationMs)
35 | 		{
36 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultResource, cacheDurationMs);
37 | 		}
38 | 
39 | 		public static void SetUrlDrawable(this ImageView imageView, string url, Drawable defaultDrawable, long cacheDurationMs)
40 | 		{
41 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultDrawable, cacheDurationMs);
42 | 		}
43 | 
44 | 		public static void SetUrlDrawable(this ImageView imageView, string url, IUrlImageViewCallback callback) 
45 | 		{
46 |         	UrlImageViewHelper.SetUrlDrawable(imageView, url, callback);
47 | 	    }
48 | 
49 | 	    public static void SetUrlDrawable(this ImageView imageView, string url, Drawable defaultDrawable, IUrlImageViewCallback callback) 
50 | 		{
51 | 	        UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultDrawable, callback);
52 | 	    }
53 | 
54 | 	    public static void SetUrlDrawable(this ImageView imageView, string url, int defaultResource, long cacheDurationMs, IUrlImageViewCallback callback) 
55 | 		{
56 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultResource, cacheDurationMs, callback);
57 | 	    }
58 | 
59 | 	    public static void SetUrlDrawable(this ImageView imageView, string url, Drawable defaultDrawable, long cacheDurationMs, IUrlImageViewCallback callback) 
60 | 		{
61 | 			UrlImageViewHelper.SetUrlDrawable(imageView, url, defaultDrawable, cacheDurationMs, callback);
62 | 	    }
63 | 	}
64 | }
65 | 
66 | 


--------------------------------------------------------------------------------
/Hashset.cs:
--------------------------------------------------------------------------------
 1 | 
 2 | using System;
 3 | using System.Collections.Generic;
 4 | using System.Linq;
 5 | using System.Text;
 6 | 
 7 | using Android.App;
 8 | using Android.Content;
 9 | using Android.OS;
10 | using Android.Runtime;
11 | using Android.Views;
12 | using Android.Widget;
13 | 
14 | namespace UrlImageViewHelper
15 | {
16 | 	public class HashTable<TKey, TValue>
17 | 	{
18 | 		object lockObj = new object();
19 | 		Dictionary<TKey, TValue> hashset = new Dictionary<TKey, TValue>();
20 | 
21 | 		public void Put(TKey key, TValue value)
22 | 		{
23 | 			lock(lockObj)
24 | 			{
25 | 				if (hashset.ContainsKey(key))
26 | 					hashset[key] = value;
27 | 				else
28 | 					hashset.Add(key, value);
29 | 			}
30 | 		}
31 | 
32 | 		public TValue Get(TKey key)
33 | 		{
34 | 			TValue result = default(TValue);
35 | 
36 | 			lock (lockObj)
37 | 			{
38 | 				if (hashset.ContainsKey(key))
39 | 					result = hashset[key];
40 | 			}
41 | 
42 | 			return result;
43 | 		}
44 | 
45 | 		public void Remove(TKey key)
46 | 		{
47 | 			lock(lockObj)
48 | 			{
49 | 				hashset.Remove(key);
50 | 			}
51 | 		}
52 | 
53 | 	}
54 | }
55 | 
56 | 


--------------------------------------------------------------------------------
/LRUCache.cs:
--------------------------------------------------------------------------------
  1 | using System;
  2 | using System.Collections.Generic;
  3 | using System.Linq;
  4 | using System.Text;
  5 | 
  6 | namespace UrlImageViewHelper
  7 | {
  8 | 	public class LRUCache<TKey, TValue> : IDictionary<TKey, TValue>
  9 | 	{
 10 | 		object sync = new object();
 11 | 		Dictionary<TKey, TValue> data;
 12 | 		IndexedLinkedList<TKey> lruList = new IndexedLinkedList<TKey>();
 13 | 		ICollection<KeyValuePair<TKey, TValue>> dataAsCollection;
 14 | 		int capacity;
 15 | 
 16 | 		public LRUCache(int capacity)
 17 | 		{
 18 | 
 19 | 			if (capacity <= 0)
 20 | 			{
 21 | 				throw new ArgumentException("capacity should always be bigger than 0");
 22 | 			}
 23 | 
 24 | 			data = new Dictionary<TKey, TValue>(capacity);
 25 | 			dataAsCollection = data;
 26 | 			this.capacity = capacity;
 27 | 		}
 28 | 
 29 | 		public void Add(TKey key, TValue value)
 30 | 		{
 31 | 			if (!ContainsKey(key))
 32 | 			{
 33 | 				this[key] = value;
 34 | 			}
 35 | 			else
 36 | 			{
 37 | 				throw new ArgumentException("An attempt was made to insert a duplicate key in the cache.");
 38 | 			}
 39 | 		}
 40 | 
 41 | 		public bool ContainsKey(TKey key)
 42 | 		{
 43 | 			return data.ContainsKey(key);
 44 | 		}
 45 | 
 46 | 		public ICollection<TKey> Keys
 47 | 		{
 48 | 			get
 49 | 			{
 50 | 				return data.Keys;
 51 | 			}
 52 | 		}
 53 | 
 54 | 		public bool Remove(TKey key)
 55 | 		{
 56 | 			bool existed = data.Remove(key);
 57 | 			lruList.Remove(key);
 58 | 			return existed;
 59 | 		}
 60 | 
 61 | 		public bool TryGetValue(TKey key, out TValue value)
 62 | 		{
 63 | 			return data.TryGetValue(key, out value);
 64 | 		}
 65 | 
 66 | 		public ICollection<TValue> Values
 67 | 		{
 68 | 			get { return data.Values; }
 69 | 		}
 70 | 
 71 | 		public TValue this[TKey key]
 72 | 		{
 73 | 			get
 74 | 			{
 75 | 				var value = data[key];
 76 | 				lruList.Remove(key);
 77 | 				lruList.Add(key);
 78 | 				return value;
 79 | 			}
 80 | 			set
 81 | 			{
 82 | 				data[key] = value;
 83 | 				lruList.Remove(key);
 84 | 				lruList.Add(key);
 85 | 
 86 | 				if (data.Count > capacity)
 87 | 				{
 88 | 					Remove(lruList.First);
 89 | 					lruList.RemoveFirst();
 90 | 				}
 91 | 			}
 92 | 		}
 93 | 
 94 | 		public void Add(KeyValuePair<TKey, TValue> item)
 95 | 		{
 96 | 			Add(item.Key, item.Value);
 97 | 		}
 98 | 
 99 | 		public void Clear()
100 | 		{
101 | 			data.Clear();
102 | 			lruList.Clear();
103 | 		}
104 | 
105 | 		public bool Contains(KeyValuePair<TKey, TValue> item)
106 | 		{
107 | 			return dataAsCollection.Contains(item);
108 | 		}
109 | 
110 | 		public void ReclaimLRU(int itemsToReclaim)
111 | 		{
112 | 			while (--itemsToReclaim >= 0 && lruList.First != null)
113 | 				Remove(lruList.First);
114 | 		}
115 | 
116 | 		public void CopyTo(KeyValuePair<TKey, TValue>[] array, int arrayIndex)
117 | 		{
118 | 			dataAsCollection.CopyTo(array, arrayIndex);
119 | 		}
120 | 
121 | 		public int Count
122 | 		{
123 | 			get { return data.Count; }
124 | 		}
125 | 
126 | 		public bool IsReadOnly
127 | 		{
128 | 			get { return false; }
129 | 		}
130 | 
131 | 		public bool Remove(KeyValuePair<TKey, TValue> item)
132 | 		{
133 | 
134 | 			bool removed = dataAsCollection.Remove(item);
135 | 			if (removed)
136 | 			{
137 | 				lruList.Remove(item.Key);
138 | 			}
139 | 			return removed;
140 | 		}
141 | 
142 | 
143 | 		public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
144 | 		{
145 | 			return dataAsCollection.GetEnumerator();
146 | 		}
147 | 
148 | 
149 | 		System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
150 | 		{
151 | 			return ((System.Collections.IEnumerable)data).GetEnumerator();
152 | 		}
153 | 
154 | 	}
155 | 
156 | 	public class IndexedLinkedList<T>
157 | 	{
158 | 
159 | 		LinkedList<T> data = new LinkedList<T>();
160 | 		Dictionary<T, LinkedListNode<T>> index = new Dictionary<T, LinkedListNode<T>>();
161 | 
162 | 		public void Add(T value)
163 | 		{
164 | 			index[value] = data.AddLast(value);
165 | 		}
166 | 
167 | 		public void RemoveFirst()
168 | 		{
169 | 			index.Remove(data.First.Value);
170 | 			data.RemoveFirst();
171 | 		}
172 | 
173 | 		public void Remove(T value)
174 | 		{
175 | 			LinkedListNode<T> node;
176 | 			if (index.TryGetValue(value, out node))
177 | 			{
178 | 				data.Remove(node);
179 | 				index.Remove(value);
180 | 			}
181 | 		}
182 | 
183 | 		public int Count
184 | 		{
185 | 			get
186 | 			{
187 | 				return data.Count;
188 | 			}
189 | 		}
190 | 
191 | 		public void Clear()
192 | 		{
193 | 			data.Clear();
194 | 			index.Clear();
195 | 		}
196 | 
197 | 		public T First
198 | 		{
199 | 			get
200 | 			{
201 | 				return data.First.Value;
202 | 			}
203 | 		}
204 | 	}
205 | 
206 | }


--------------------------------------------------------------------------------
/MonoDroid.UrlImageViewHelper.csproj:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="utf-8"?>
 2 | <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
 3 |   <PropertyGroup>
 4 |     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
 5 |     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
 6 |     <ProductVersion>10.0.0</ProductVersion>
 7 |     <SchemaVersion>2.0</SchemaVersion>
 8 |     <ProjectGuid>{57444E6A-23D9-443A-BA83-040CB9561E66}</ProjectGuid>
 9 |     <ProjectTypeGuids>{EFBA0AD7-5A72-4C68-AF49-83D382785DCF};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
10 |     <OutputType>Library</OutputType>
11 |     <RootNamespace>UrlImageViewHelper</RootNamespace>
12 |     <MonoAndroidResourcePrefix>Resources</MonoAndroidResourcePrefix>
13 |     <MonoAndroidAssetsPrefix>Assets</MonoAndroidAssetsPrefix>
14 |     <AssemblyName>UrlImageViewHelper</AssemblyName>
15 |   </PropertyGroup>
16 |   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
17 |     <DebugSymbols>True</DebugSymbols>
18 |     <DebugType>full</DebugType>
19 |     <Optimize>False</Optimize>
20 |     <OutputPath>bin\Debug</OutputPath>
21 |     <DefineConstants>DEBUG;</DefineConstants>
22 |     <ErrorReport>prompt</ErrorReport>
23 |     <WarningLevel>4</WarningLevel>
24 |     <ConsolePause>False</ConsolePause>
25 |     <AndroidLinkMode>None</AndroidLinkMode>
26 |   </PropertyGroup>
27 |   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
28 |     <DebugType>none</DebugType>
29 |     <Optimize>True</Optimize>
30 |     <OutputPath>bin\Release</OutputPath>
31 |     <ErrorReport>prompt</ErrorReport>
32 |     <WarningLevel>4</WarningLevel>
33 |     <ConsolePause>False</ConsolePause>
34 |     <AndroidLinkMode>SdkOnly</AndroidLinkMode>
35 |     <AndroidUseSharedRuntime>False</AndroidUseSharedRuntime>
36 |   </PropertyGroup>
37 |   <ItemGroup>
38 |     <Reference Include="System" />
39 |     <Reference Include="System.Xml" />
40 |     <Reference Include="System.Core" />
41 |     <Reference Include="Mono.Android" />
42 |   </ItemGroup>
43 |   <Import Project="$(MSBuildExtensionsPath)\Novell\Novell.MonoDroid.CSharp.targets" />
44 |   <ItemGroup>
45 |     <Compile Include="LRUCache.cs" />
46 |     <Compile Include="SoftReference.cs" />
47 |     <Compile Include="SoftReferenceHashTable.cs" />
48 |     <Compile Include="UrlImageCache.cs" />
49 |     <Compile Include="UrlImageViewCallback.cs" />
50 |     <Compile Include="UrlImageViewHelper.cs" />
51 |     <Compile Include="DownloaderAsyncTask.cs" />
52 |     <Compile Include="Hashset.cs" />
53 |     <Compile Include="ExtensionMethods.cs" />
54 |   </ItemGroup>
55 | </Project>


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | MonoDroid.UrlImageViewHelper
 2 | ============================
 3 | 
 4 | C# / Mono for Android Port of koush's UrlImageViewHelper
 5 | 
 6 | You can see Koush's original project here: https://github.com/koush/UrlImageViewHelper
 7 | 
 8 | Sample Usage
 9 | ------------
10 | 
11 | It's really easy to use, there are a number of ExtensionMethods in the UrlImageViewHelper namespace for the ImageView class that take a couple different arguments as options.  Here's a very simple example of loading an image from a url, but initially displaying a default image while the image from a url is loading:
12 | 
13 | ```csharp
14 | var img = this.FindViewById<ImageView>(Resource.Id.SomeImageView);
15 | img.SetUrlDrawable("http://site.com/image.png", Resource.Drawable.DefaultUrlImage);
16 | ```
17 | 


--------------------------------------------------------------------------------
/SoftReference.cs:
--------------------------------------------------------------------------------
 1 | using System;
 2 | using System.Collections.Generic;
 3 | using System.Linq;
 4 | using System.Text;
 5 | 
 6 | using Android.App;
 7 | using Android.Content;
 8 | using Android.OS;
 9 | using Android.Runtime;
10 | using Android.Views;
11 | using Android.Widget;
12 | 
13 | namespace UrlImageViewHelper
14 | {
15 |     //class SoftReference : WeakReference { public SoftReference(object target) : base(target) { NonWebCache[Guid.NewGuid().ToString()] = target; } }
16 | 
17 |     // Switched to trusting the GC for mono, so using WeakReference instead
18 |    // public class SoftReference<T> : WeakReference /* where T : Object */ { 
19 |    //     public SoftReference(T target) : base(target)
20 |    //     {
21 |    //     }
22 | 	public class SoftReference<T> 
23 | 	{
24 | 		public SoftReference(T target)
25 | 		{
26 | 			_target = target;
27 | 		}
28 | 
29 | 		T _target = default(T);
30 | 
31 |         public T Get()
32 |         {
33 | 			return _target;
34 | 
35 | 			//Android.Util.Log.Debug(UrlImageViewHelper.LOGTAG, "SoftReference OK? " + base.IsAlive.ToString());
36 | 
37 | 			//if (!base.IsAlive)
38 | 			//{
39 | 			//	Android.Util.Log.Debug(UrlImageViewHelper.LOGTAG, "Lost SoftReference");
40 | 			//	return default(T);
41 | 				
42 | 			//	//throw new Exception("Lost SoftReference");
43 | 			//}
44 | 			//return (T)base.Target;
45 |         }
46 |     }
47 | }


--------------------------------------------------------------------------------
/SoftReferenceHashTable.cs:
--------------------------------------------------------------------------------
  1 | 
  2 | using System;
  3 | using System.Collections;
  4 | using System.Collections.Generic;
  5 | using System.Linq;
  6 | using System.Text;
  7 | 
  8 | using Android.App;
  9 | using Android.Content;
 10 | using Android.OS;
 11 | using Android.Runtime;
 12 | using Android.Views;
 13 | using Android.Widget;
 14 | 
 15 | namespace UrlImageViewHelper
 16 | {
 17 | 	public class SoftReferenceHashTable<TKey, TValue>
 18 | 	{
 19 | 		/*
 20 | 		Dictionary<TKey, SoftReference<TValue>> table = new Dictionary<TKey, SoftReference<TValue>>();
 21 | 		
 22 | 		public TValue Put(TKey key, TValue value)
 23 | 		{
 24 | 			var newVal = new SoftReference<TValue>(value);
 25 | 
 26 | 			if (table.ContainsKey(key))
 27 | 				table[key] = newVal;
 28 | 			else
 29 | 				table.Add(key, newVal);
 30 | 
 31 | 			return newVal.Get();
 32 | 		}
 33 | 
 34 | 		public TValue Get(TKey key)
 35 | 		{
 36 | 			if (!table.ContainsKey(key))
 37 | 				return default(TValue);
 38 | 
 39 | 			var val = table[key];
 40 | 
 41 | 			if (val == null || val.Get() == null)
 42 | 			{
 43 | 				Android.Util.Log.Debug(UrlImageViewHelper.LOGTAG, key.ToString() + " Lost Reference");
 44 | 				table.Remove(key);
 45 | 				return default(TValue);
 46 | 			}
 47 | 
 48 | 			return val.Get();
 49 | 		}
 50 | 		 */
 51 | 
 52 | 		object cacheLock = new object();
 53 | 		LRUCache<TKey, TValue> cache = new LRUCache<TKey, TValue>(100);
 54 | 
 55 | 		public TValue Put(TKey key, TValue value)
 56 | 		{
 57 | 			//var newVal = new SoftReference<TValue>(value);
 58 | 			lock (cacheLock)
 59 | 			{
 60 | 				if (cache.ContainsKey(key))
 61 | 					cache[key] = value;
 62 | 				else
 63 | 					cache.Add(key, value);
 64 | 
 65 | 				return value;
 66 | 			}
 67 | 		}
 68 | 
 69 | 		public TValue Get(TKey key)
 70 | 		{
 71 | 			lock (cacheLock)
 72 | 			{
 73 | 				if (!cache.ContainsKey(key))
 74 | 					return default(TValue);
 75 | 
 76 | 				var val = cache[key];
 77 | 
 78 | 				if (val == null)
 79 | 				{
 80 | 					Android.Util.Log.Debug(UrlImageViewHelper.LOGTAG, key.ToString() + " Lost Reference");
 81 | 					cache.Remove(key);
 82 | 					return default(TValue);
 83 | 				}
 84 | 
 85 | 				return val;
 86 | 			}
 87 | 		}
 88 | //		
 89 | //		 Hashtable<K, SoftReference<V>> mTable = new Hashtable<K, SoftReference<V>>();
 90 | //    
 91 | //    public V put(K key, V value) {
 92 | //        SoftReference<V> old = mTable.put(key, new SoftReference<V>(value));
 93 | //        if (old == null)
 94 | //            return null;
 95 | //        return old.get();
 96 | //    }
 97 | //    
 98 | //    public V get(K key) {
 99 | //        SoftReference<V> val = mTable.get(key);
100 | //        if (val == null)
101 | //            return null;
102 | //        V ret = val.get();
103 | //        if (ret == null)
104 | //            mTable.remove(key);
105 | //        return ret;
106 | //    }
107 | 	}
108 | }
109 | 
110 | 


--------------------------------------------------------------------------------
/UrlImageCache.cs:
--------------------------------------------------------------------------------
 1 | 
 2 | using System;
 3 | using System.Collections.Generic;
 4 | using System.Linq;
 5 | using System.Text;
 6 | 
 7 | using Android.App;
 8 | using Android.Content;
 9 | using Android.Graphics.Drawables;
10 | using Android.OS;
11 | using Android.Runtime;
12 | using Android.Views;
13 | using Android.Widget;
14 | 
15 | namespace UrlImageViewHelper
16 | {
17 | 	public class UrlImageCache : SoftReferenceHashTable<string, Drawable>
18 | 	{
19 | 		static UrlImageCache instance;
20 | 
21 | 		public static UrlImageCache Instance
22 | 		{
23 | 			get 
24 | 			{ 
25 | 				if (instance == null) 
26 | 					instance = new UrlImageCache(); 
27 | 			
28 | 				return instance;
29 | 			}
30 | 		}
31 | 
32 | 
33 | 	}
34 | }
35 | 
36 | 


--------------------------------------------------------------------------------
/UrlImageViewCallback.cs:
--------------------------------------------------------------------------------
 1 | 
 2 | using System;
 3 | using System.Collections.Generic;
 4 | using System.Linq;
 5 | using System.Text;
 6 | 
 7 | using Android.App;
 8 | using Android.Content;
 9 | using Android.Graphics.Drawables;
10 | using Android.OS;
11 | using Android.Runtime;
12 | using Android.Views;
13 | using Android.Widget;
14 | 
15 | namespace UrlImageViewHelper
16 | {
17 | 	public interface IUrlImageViewCallback
18 | 	{
19 | 		void OnLoaded(ImageView imageView, Drawable loadedDrawable, string url, bool loadedFromCache);
20 | 	}
21 | }
22 | 
23 | 


--------------------------------------------------------------------------------
/UrlImageViewHelper.cs:
--------------------------------------------------------------------------------
  1 | 
  2 | using System;
  3 | using System.Collections.Generic;
  4 | using System.Linq;
  5 | using System.Text;
  6 | 
  7 | using Android.App;
  8 | using Android.Content;
  9 | using Android.Graphics.Drawables;
 10 | using Android.OS;
 11 | using Android.Runtime;
 12 | using Android.Views;
 13 | using Android.Widget;
 14 | 
 15 | namespace UrlImageViewHelper
 16 | {
 17 | 	public class UrlImageViewHelper
 18 | 	{
 19 | 		public const string LOGTAG = "UrlImageViewHelper";
 20 | 		public const int CACHE_DURATION_INFINITE = int.MaxValue;
 21 |     	public const int CACHE_DURATION_ONE_DAY = 1000 * 60 * 60 * 24;
 22 |     	public const int CACHE_DURATION_TWO_DAYS = CACHE_DURATION_ONE_DAY * 2;
 23 |     	public const int CACHE_DURATION_THREE_DAYS = CACHE_DURATION_ONE_DAY * 3;
 24 |     	public const int CACHE_DURATION_FOUR_DAYS = CACHE_DURATION_ONE_DAY * 4;
 25 |     	public const int CACHE_DURATION_FIVE_DAYS = CACHE_DURATION_ONE_DAY * 5;
 26 |     	public const int CACHE_DURATION_SIX_DAYS = CACHE_DURATION_ONE_DAY * 6;
 27 |     	public const int CACHE_DURATION_ONE_WEEK = CACHE_DURATION_ONE_DAY * 7;
 28 | 
 29 | 		public static void SetUrlDrawable(ImageView imageView, string url, int defaultResource)
 30 | 		{
 31 | 			SetUrlDrawable(imageView.Context, imageView, url, defaultResource, CACHE_DURATION_THREE_DAYS);
 32 | 		}
 33 | 
 34 | 		public static void SetUrlDrawable(ImageView imageView, string url)
 35 | 		{
 36 | 			SetUrlDrawable(imageView.Context, imageView, url, null, CACHE_DURATION_THREE_DAYS, null);
 37 | 		}
 38 | 
 39 | 		public static void LoadDrawable(Context context, string url)
 40 | 		{
 41 | 			 SetUrlDrawable(context, null, url, null, CACHE_DURATION_THREE_DAYS, null);
 42 | 		}
 43 | 
 44 | 		public static void SetUrlDrawable(ImageView imageView, string url, Drawable defaultDrawable)
 45 | 		{
 46 | 			SetUrlDrawable(imageView.Context, imageView, url, defaultDrawable, CACHE_DURATION_THREE_DAYS, null);
 47 | 		}
 48 | 
 49 | 		public static void SetUrlDrawable(ImageView imageView, string url, int defaultResource, long cacheDurationMs)
 50 | 		{
 51 | 			SetUrlDrawable(imageView.Context, imageView, url, defaultResource, cacheDurationMs);
 52 | 		}
 53 | 
 54 | 		public static void LoadUrlDrawable(Context context, string url, long cacheDurationMs)
 55 | 		{
 56 | 			SetUrlDrawable(context, null, url, null, cacheDurationMs, null);
 57 | 		}
 58 | 
 59 | 		public static void SetUrlDrawable(ImageView imageView, string url, Drawable defaultDrawable, long cacheDurationMs)
 60 | 		{
 61 | 			SetUrlDrawable(imageView.Context, imageView, url, defaultDrawable, cacheDurationMs, null);
 62 | 		}
 63 | 
 64 | 		private static void SetUrlDrawable(Context context, ImageView imageView, string url, int defaultResource, long cacheDurationMs)
 65 | 		{
 66 | 			Drawable d = null;
 67 | 			if (defaultResource != 0)
 68 | 				d = imageView.Resources.GetDrawable(defaultResource);
 69 | 			SetUrlDrawable(context, imageView, url, d, cacheDurationMs, null);
 70 | 		}
 71 | 
 72 | 		public static void SetUrlDrawable(ImageView imageView, string url, IUrlImageViewCallback callback) 
 73 | 		{
 74 |         	SetUrlDrawable(imageView.Context, imageView, url, null, CACHE_DURATION_THREE_DAYS, callback);
 75 | 	    }
 76 | 
 77 | 	    public static void LoadUrlDrawable(Context context, string url, IUrlImageViewCallback callback) 
 78 | 		{
 79 | 	        SetUrlDrawable(context, null, url, null, CACHE_DURATION_THREE_DAYS, callback);
 80 | 	    }
 81 | 
 82 | 	    public static void SetUrlDrawable(ImageView imageView, string url, Drawable defaultDrawable, IUrlImageViewCallback callback) 
 83 | 		{
 84 | 	        SetUrlDrawable(imageView.Context, imageView, url, defaultDrawable, CACHE_DURATION_THREE_DAYS, callback);
 85 | 	    }
 86 | 
 87 | 	    public static void SetUrlDrawable(ImageView imageView, string url, int defaultResource, long cacheDurationMs, IUrlImageViewCallback callback) 
 88 | 		{
 89 | 	        SetUrlDrawable(imageView.Context, imageView, url, defaultResource, cacheDurationMs, callback);
 90 | 	    }
 91 | 
 92 | 	    public static void LoadUrlDrawable(Context context, string url, long cacheDurationMs, IUrlImageViewCallback callback) 
 93 | 		{
 94 | 	        SetUrlDrawable(context, null, url, null, cacheDurationMs, callback);
 95 | 	    }
 96 | 
 97 | 	    public static void SetUrlDrawable(ImageView imageView, string url, Drawable defaultDrawable, long cacheDurationMs, IUrlImageViewCallback callback) 
 98 | 		{
 99 | 	        SetUrlDrawable(imageView.Context, imageView, url, defaultDrawable, cacheDurationMs, callback);
100 | 	    }
101 | 
102 | 	    private static void SetUrlDrawable(Context context, ImageView imageView, string url, int defaultResource, long cacheDurationMs, IUrlImageViewCallback callback) 
103 | 		{
104 | 	        Drawable d = null;
105 | 	        if (defaultResource != 0)
106 | 				d = imageView.Resources.GetDrawable(defaultResource);
107 | 	        SetUrlDrawable(context, imageView, url, d, cacheDurationMs, callback);
108 | 	    }
109 | 
110 | 		protected static HashTable<ImageView, string> pendingViews = new HashTable<ImageView, string>();
111 | 		protected static HashTable<string, List<ImageView>> pendingDownloads = new HashTable<string, List<ImageView>>();
112 | 		static bool hasCleaned = false;
113 | 
114 | 		static Android.Content.Res.Resources mResources;
115 |     	static Android.Util.DisplayMetrics mMetrics;
116 | 	    
117 | 		private static void PrepareResources(Context context) 
118 | 		{
119 | 	        if (mMetrics != null)
120 | 	            return;
121 | 			mMetrics = new Android.Util.DisplayMetrics();
122 | 	        Activity act = (Activity)context;
123 | 			act.WindowManager.DefaultDisplay.GetMetrics(mMetrics);
124 | 			var mgr = context.Assets;
125 | 	        mResources = new Android.Content.Res.Resources(mgr, mMetrics, context.Resources.Configuration);
126 | 	    }
127 | 
128 | 	    public static BitmapDrawable LoadDrawableFromFile(Context context, string filename) 
129 | 		{
130 | 	        PrepareResources(context);
131 | 	        
132 | 			var bitmap = Android.Graphics.BitmapFactory.DecodeFile(filename);
133 | 
134 | 			//var bitmap = Android.Graphics.BitmapFactory.DecodeStream(stream);
135 | 	        //Log.i(LOGTAG, String.format("Loaded bitmap (%dx%d).", bitmap.getWidth(), bitmap.getHeight()));
136 | 	        return new BitmapDrawable(mResources, bitmap);
137 | 	    }
138 | 
139 | 		private static void Cleanup(Context context)
140 | 		{
141 | 			if (hasCleaned)
142 | 				return;
143 | 
144 | 			hasCleaned = true;
145 | 
146 | 			try
147 | 			{
148 | 				var baseDir = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
149 | 
150 | 				var files = System.IO.Directory.GetFiles(baseDir);
151 | 
152 | 				if (files == null || files.Length <= 0)
153 | 					return;
154 | 
155 | 				foreach (var file in files)
156 | 				{
157 | 					if (!file.EndsWith(".urlimage"))
158 | 						continue;
159 | 
160 | 					
161 | 					var f = new System.IO.FileInfo(file);
162 | 					if (DateTime.UtcNow > f.LastWriteTimeUtc)
163 | 						f.Delete();
164 | 				}
165 | 			}
166 | 			catch { }
167 | 		}
168 | 
169 | 		private static string GetFilenameForUrl(string url)
170 | 		{
171 | 			var hashCode = url.GetHashCode().ToString().Replace("-", "N");
172 | 			return hashCode + ".urlimage";
173 | 		}
174 | 
175 | 		private static void SetUrlDrawable(Context context, ImageView imageView, string url, Drawable defaultDrawable, long cacheDurationMs, IUrlImageViewCallback callback)
176 | 		{
177 | 			Cleanup(context);
178 | 
179 | 			if (imageView != null)
180 | 				pendingViews.Remove(imageView);
181 | 
182 | 			if (string.IsNullOrEmpty(url))
183 | 			{
184 | 				if (imageView != null)
185 | 					imageView.SetImageDrawable(defaultDrawable);
186 | 
187 | 				return;
188 | 			}
189 | 
190 | 			var cache = UrlImageCache.Instance;
191 | 			var drawable = cache.Get(url);
192 | 
193 | 			if (drawable != null)
194 | 			{
195 | 				if (imageView != null)
196 | 					imageView.SetImageDrawable(drawable);
197 | 				if (callback != null)
198 | 					callback.OnLoaded(imageView, drawable, url, true);
199 | 				return;
200 | 			}
201 | 
202 | 			var baseDir = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
203 | 			var filename = System.IO.Path.Combine(baseDir, GetFilenameForUrl(url));
204 | 					
205 | 			var file = new System.IO.FileInfo(filename);
206 | 			if (file.Exists)
207 | 			{
208 | 				try
209 | 				{
210 | 					if (cacheDurationMs == CACHE_DURATION_INFINITE || DateTime.UtcNow < file.LastWriteTimeUtc.AddMilliseconds(cacheDurationMs))
211 | 					{
212 | 						drawable = LoadDrawableFromFile(context, filename);
213 | 						//var fis = context.OpenFileInput(filename);
214 | 						//drawable = LoadDrawableFromStream(context, fis);
215 | 						//fis.Close();
216 | 
217 | 						if (imageView != null)
218 | 							imageView.SetImageDrawable(drawable);
219 | 
220 | 						cache.Put(url, drawable);
221 | 
222 | 						if (callback != null)
223 | 							callback.OnLoaded(imageView, drawable, url, true);
224 | 
225 | 						return;
226 | 					}
227 | 					else
228 | 					{
229 | 						//TODO: File cache expired, refreshing
230 | 						Android.Util.Log.Debug(LOGTAG, "File Cache Expired: " + file.Name);
231 | 					}
232 | 				}
233 | 				catch (Exception ex)
234 | 				{
235 | 					Android.Util.Log.Debug(LOGTAG, "File Cache Exception " + ex.ToString());
236 | 				}
237 | 			}
238 | 
239 | 			if (imageView != null)
240 | 				imageView.SetImageDrawable(defaultDrawable);
241 | 
242 | 			if (imageView != null)
243 | 				pendingViews.Put(imageView, url);
244 | 
245 | 			//Check to see if another view is already waiting for this url so we don't download it again
246 | 			var currentDownload = pendingDownloads.Get(url);
247 | 			if (currentDownload != null)
248 | 			{
249 | 				if (imageView != null)
250 | 					currentDownload.Add(imageView);
251 | 
252 | 				return;
253 | 			}
254 | 
255 | 			var downloads = new List<ImageView>();
256 | 			if (imageView != null)
257 | 				downloads.Add(imageView);
258 | 
259 | 			pendingDownloads.Put(url, downloads);
260 | 
261 | 			var downloaderTask = new AnonymousAsyncTask<string, string, BitmapDrawable>((p) => 
262 | 			{
263 | 				try
264 | 				{
265 | 					var client = new System.Net.WebClient();
266 | 					var data = client.DownloadData(url);
267 | 
268 | 					System.IO.File.WriteAllBytes(filename, data);
269 | 
270 | 					return LoadDrawableFromFile(context, filename);
271 | 				}
272 | 				catch (Exception ex) 
273 | 				{
274 | 					Android.Util.Log.Debug(LOGTAG, "Download Error: " + ex.ToString());
275 | 					return null; 
276 | 				}
277 | 
278 | 
279 | 			}, (bd) => 
280 | 			{
281 | 				try
282 | 				{
283 | 					var usableResult = bd;
284 | 					if (usableResult == null)
285 | 						usableResult = (BitmapDrawable)defaultDrawable;
286 | 
287 | 					pendingDownloads.Remove(url);
288 | 
289 | 					cache.Put(url, usableResult);
290 | 
291 | 					foreach (var iv in downloads)
292 | 					{
293 | 						var pendingUrl = pendingViews.Get (iv);
294 | 						if (!url.Equals(pendingUrl))
295 | 							continue;
296 | 						pendingViews.Remove(iv);
297 | 
298 | 						if (usableResult != null)
299 | 						{
300 | 							var fnewImage = usableResult;
301 | 							var fimageView = iv;
302 | 
303 | 							fimageView.SetImageDrawable(fnewImage);
304 | 
305 | 							if (callback != null)
306 | 								callback.OnLoaded(fimageView, bd, url, false);
307 | 						}
308 | 					}
309 | 				}
310 | 				catch (Exception ex)
311 | 				{
312 | 					Android.Util.Log.Debug(LOGTAG, "PostExecute Error: " + ex.ToString()); 
313 | 				}
314 | 
315 | 			});
316 | 
317 | 			downloaderTask.Execute(new Java.Lang.Object[]{});
318 | 		}
319 | 	}
320 | }
321 | 
322 | 


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