ComponentResourceKey as DynamicResource问题

Question

我在使用ComponentResourceKey时看到了一些意想不到的行为。出现这个问题是因为我使用了SystemColors类中使用的名称。

考虑以下代码：

首先，我将a中的ComponentResourceKey公开为静态属性：

public enum ColorKeys
{
    ControlColor
}

public class MyColors
{
    public static ComponentResourceKey ControlColorKey
    {
        get 
        { 
            return new ComponentResourceKey(typeof(MyColors), ColorKeys.ControlColor); 
        }
    }
}

使用标记中的键将资源分配给该键。使用ComponentResourceKey标记将该资源作为DynamicResource调用是可行的。但是使用静态属性调用相同的资源将解析为SystemColors.ControlColorKey资源。

下面是xaml：

<Window.Resources>
    <Color x:Key="{x:Static l:MyColors.ControlColorKey}">#FF0000FF</Color>
    <SolidColorBrush x:Key="UsingVerbose" 
                     Color="{DynamicResource {ComponentResourceKey TypeInTargetAssembly={x:Type l:MyColors}, 
                                ResourceId={x:Static l:ColorKeys.ControlColor}}}"/>
    <SolidColorBrush x:Key="UsingStatic" 
                     Color="{DynamicResource {x:Static l:MyColors.ControlColorKey}}"/>                
</Window.Resources>
<Grid>
    <StackPanel>
        <Button Height="20" Width="80" Background="{DynamicResource UsingVerbose}" Content="Verbose"/>
        <Button Height="20" Width="80" Background="{DynamicResource UsingStatic}" Content="Static"/>
    </StackPanel>
</Grid>

当窗口显示时，"Verbose“按钮相应地显示蓝色背景。但下方的“静态”按钮显示的是SystemColors.ControlColorKey颜色。

将静态属性的名称更改为另一个名称可使两个画笔都解析为正确的颜色。

但是我不确定为什么DynamicResource对于键的静态实例和由标记实例化的实例的解析是不同的？

谢谢,

K

PS:下面是ResourceDictionarySource的相关跟踪输出

System.Windows.ResourceDictionary Start: 10 : New resource dictionary set; Owner='TestMergedDictionaries.Window1'; Owner.HashCode='64923656'; Owner.Type='TestMergedDictionaries.Window1'; OldDictionary='0'; NewDictionary='System.Windows.ResourceDictionary'; NewDictionary.HashCode='44624228'; NewDictionary.Type='System.Windows.ResourceDictionary'
System.Windows.ResourceDictionary Stop: 10 : 
System.Windows.ResourceDictionary Start: 12 : Deferred resource has been added to ResourceDictionary; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'
System.Windows.ResourceDictionary Stop: 12 : 
System.Windows.ResourceDictionary Start: 12 : Deferred resource has been added to ResourceDictionary; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='UsingVerbose'
System.Windows.ResourceDictionary Stop: 12 : 
System.Windows.ResourceDictionary Start: 12 : Deferred resource has been added to ResourceDictionary; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='UsingStatic'
System.Windows.ResourceDictionary Stop: 12 : 
System.Windows.ResourceDictionary Start: 11 : Searching for resource; Element='System.Windows.Controls.Button'; Element.HashCode='52727599'; Element.Type='System.Windows.Controls.Button'; ResourceKey='UsingVerbose'
System.Windows.ResourceDictionary Start: 3 : Found resource item on an element; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='UsingVerbose'; Value='System.Windows.DeferredResourceReference'; Value.HashCode='14347911'; Value.Type='System.Windows.DeferredResourceReference'
System.Windows.ResourceDictionary Stop: 3 : 
System.Windows.ResourceDictionary Stop: 11 : Searching for resource; Element='System.Windows.Controls.Button'; Element.HashCode='52727599'; Element.Type='System.Windows.Controls.Button'; ResourceKey='UsingVerbose'

... removed uninteresting traces ...

System.Windows.ResourceDictionary Start: 11 : Searching for resource; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'
System.Windows.ResourceDictionary Start: 3 : Found resource item on an element; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'; Value='System.Windows.DeferredResourceReference'; Value.HashCode='23488915'; Value.Type='System.Windows.DeferredResourceReference'
System.Windows.ResourceDictionary Stop: 3 : 
System.Windows.ResourceDictionary Stop: 11 : Searching for resource; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'

System.Windows.ResourceDictionary Start: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='23264094'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='System.Windows.Controls.TextBlock'; Value='DefAttributeKeyType typeId=TextBlock'; Value.HashCode='23521433'; Value.Type='System.Windows.Markup.BamlDefAttributeKeyTypeRecord'
System.Windows.ResourceDictionary Stop: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='23264094'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='System.Windows.Controls.TextBlock'; Value='System.Windows.Style'; Value.HashCode='5'; Value.Type='System.Windows.Style'

System.Windows.ResourceDictionary Start: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='UsingStatic'; Value='DefAttributeKeyString'; Value.HashCode='24854661'; Value.Type='System.Windows.Markup.BamlDefAttributeKeyStringRecord'
System.Windows.ResourceDictionary Start: 11 : Searching for resource; Element=''; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'
System.Windows.ResourceDictionary Start: 8 : Found resource item in theme; Dictionary='System.Windows.SystemResourceHost'; Dictionary.HashCode='65273341'; Dictionary.Type='System.Windows.SystemResourceHost'; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'; Value='#FFF0F0F0'
System.Windows.ResourceDictionary Stop: 8 : 
System.Windows.ResourceDictionary Stop: 11 : Searching for resource; Element=''; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'
System.Windows.ResourceDictionary Stop: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='UsingStatic'; Value='#FFF0F0F0'; Value.HashCode='12408161'; Value.Type='System.Windows.Media.SolidColorBrush'

System.Windows.ResourceDictionary Start: 11 : Searching for resource; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'
System.Windows.ResourceDictionary Start: 8 : Found resource item in theme; Dictionary='System.Windows.SystemResourceHost'; Dictionary.HashCode='65273341'; Dictionary.Type='System.Windows.SystemResourceHost'; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'; Value='#FFF0F0F0'
System.Windows.ResourceDictionary Stop: 8 : 
System.Windows.ResourceDictionary Stop: 11 : Searching for resource; Element='TestMergedDictionaries.Window1'; Element.HashCode='64923656'; Element.Type='TestMergedDictionaries.Window1'; ResourceKey='ControlColor'; ResourceKey.HashCode='35'; ResourceKey.Type='System.Windows.SystemResourceKey'

System.Windows.ResourceDictionary Start: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'; Value='KeyElementStart typeId=StaticExtension'; Value.HashCode='54371668'; Value.Type='System.Windows.Markup.BamlKeyElementStartRecord'
System.Windows.ResourceDictionary Stop: 2 : Delayed creation of resource; Dictionary='System.Windows.ResourceDictionary'; Dictionary.HashCode='44624228'; Dictionary.Type='System.Windows.ResourceDictionary'; ResourceKey='TargetType=TestMergedDictionaries.MyColors ID=ControlColor'; ResourceKey.HashCode='1936592'; ResourceKey.Type='System.Windows.ComponentResourceKey'; Value='#FF0000FF'

Answer 1

在静态ControlColorKey中，每次访问getter时都会创建一个新的ComponentResourceKey实例。因此，第二次使用引用了不同的对象，并且没有获得更新后的颜色。如果您将代码更改为简单的静态字段，它将按预期工作：

public static ComponentResourceKey ControlColorKey = new ComponentResourceKey(typeof(MyColors), ColorKeys.ControlColor);