MyImage 控件

Plain Craft Launcher 2/Controls/MyImage.vb

@@ -0,0 +1,73 @@
+Imports System.Threading.Tasks
+
+Public Class MyImage
+    Inherits Image
+
+    '事件
+
+    Private _SourceData As String = ""
+    Private _UseCache As Boolean = False
+    Private _DownloadTask As Task
+
+    Private FileCacheExpiredTime As TimeSpan = New TimeSpan(7, 0, 0, 0) ' 一个星期的缓存有效期
+
+    Public Property UseCache As Boolean
+        Get
+            Return _UseCache
+        End Get
+        Set(value As Boolean)
+            _UseCache = value
+        End Set
+    End Property
+
+    ''' <summary>
+    ''' 重写Image的Source属性
+    ''' </summary>
+    Public Shadows Property Source As String
+        Get
+            Return _SourceData
+        End Get
+        Set(value As String)
+            If String.IsNullOrEmpty(value) Then Exit Property
+            _SourceData = value
+            Try
+                If Not value.StartsWithF("http") Then ' 本地资源直接使用
+                    MyBase.Source = New MyBitmap(_SourceData)
+                    Exit Property
+                End If
+                If _DownloadTask IsNot Nothing AndAlso Not _DownloadTask.IsCompleted Then ' 之前下载任务还在，直接砍了
+                    _DownloadTask.Dispose()
+                End If
+                Dim NeedDownload As Boolean = True '是否需要下载/本地是否有有效缓存
+                Dim TempFilePath As String = PathTemp & "Cache\MyImage\" & GetHash(_SourceData) & ".png"
+                If _UseCache And File.Exists(TempFilePath) And (DateTime.Now - File.GetCreationTime(TempFilePath)) < FileCacheExpiredTime Then NeedDownload = False ' 缓存文件存在且未过期，不需要重下
+                If Not NeedDownload Then
+                    MyBase.Source = New MyBitmap(TempFilePath)
+                    Exit Property
+                End If
+                ' 异步下载图片
+                Dim TaskID = 0
+                _DownloadTask = New Task(Sub()
+                                             NetDownload(_SourceData, TempFilePath, True)
+                                         End Sub)
+                TaskID = _DownloadTask.Id
+                _DownloadTask.Start()
+                _DownloadTask.ContinueWith(Sub(t)
+                                               If t.IsCompleted AndAlso t.Id = TaskID Then ' 任务没有被干掉
+                                                   MyBase.Source = New MyBitmap(TempFilePath)
+                                               End If
+                                           End Sub, TaskScheduler.FromCurrentSynchronizationContext())
+            Catch ex As Exception
+                Log(ex, "加载图片失败")
+            End Try
+        End Set
+    End Property
+    Public Shared Shadows ReadOnly SourceProperty As DependencyProperty = DependencyProperty.Register("Source", GetType(String), GetType(MyImage), New PropertyMetadata(New PropertyChangedCallback(
+                                                                                                                                                               Sub(sender As DependencyObject, e As DependencyPropertyChangedEventArgs)
+                                                                                                                                                                   If Not IsNothing(sender) Then
+                                                                                                                                                                       If String.IsNullOrEmpty(e.NewValue.ToString()) Then Exit Sub
+                                                                                                                                                                       CType(sender, MyImage).Source = e.NewValue.ToString()
+                                                                                                                                                                   End If
+                                                                                                                                                               End Sub)))
+
+End Class

Plain Craft Launcher 2/Modules/Base/MyBitmap.vb

@@ -152,4 +152,4 @@ Public Class MyBitmap
         End Using
     End Sub
 
-End Class
+End Class

Plain Craft Launcher 2/Plain Craft Launcher 2.vbproj

@@ -191,9 +191,7 @@
     <Compile Include="Controls\MyIconTextButton.xaml.vb">
       <DependentUpon>MyIconTextButton.xaml</DependentUpon>
     </Compile>
-
-
-
+    <Compile Include="Controls\MyImage.vb" />
     <Compile Include="Modules\Minecraft\ModComp.vb" />
     <Compile Include="Modules\Minecraft\ModJava.vb" />
     <Compile Include="Modules\Minecraft\ModMod.vb" />
@@ -478,7 +476,6 @@
       <DependentUpon>FormMain.xaml</DependentUpon>
       <SubType>Code</SubType>
     </Compile>
-
     <Page Include="Modules\Minecraft\MyLocalModItem.xaml">
       <Generator>MSBuild:Compile</Generator>
       <SubType>Designer</SubType>
@@ -913,7 +910,6 @@
     <Resource Include="Images\Heads\MCBBS.png" />
   </ItemGroup>
   <ItemGroup>
-
   </ItemGroup>
   <ItemGroup>
     <Resource Include="Images\Blocks\NeoForge.png" />