我尝试在将控件添加到UI的同时，将样式资源合并到应用资源中，为我的自定义控件应用新的样式，但是第一次应用新的样式并没有应用到控件中。
控件示例
自定义TextBoxExt.cs
public class CustomTextBoxExt : TextBox
{
static CustomTextBoxExt()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(CustomTextBoxExt), new FrameworkPropertyMetadata(typeof(CustomTextBoxExt)));
}
}
默认styleGeneric.xaml
<Style x:Key="TextBoxExtStyle" TargetType="{x:Type local:CustomTextBoxExt}">
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}" />
<Setter Property="BorderBrush" Value="Red" />
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="KeyboardNavigation.TabNavigation" Value="None" />
<Setter Property="HorizontalContentAlignment" Value="Left" />
<Setter Property="FocusVisualStyle" Value="{x:Null}" />
<Setter Property="AllowDrop" Value="True" />
<Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst" />
<Setter Property="Stylus.IsFlicksEnabled" Value="False" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:CustomTextBoxExt}">
<Border
x:Name="border"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="True">
<ScrollViewer
x:Name="PART_ContentHost"
Focusable="False"
HorizontalScrollBarVisibility="Hidden"
VerticalScrollBarVisibility="Hidden" />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="border" Property="Opacity" Value="0.56" />
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="#FF7EB4EA" />
</Trigger>
<Trigger Property="IsKeyboardFocused" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="#FF569DE5" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsInactiveSelectionHighlightEnabled" Value="True" />
<Condition Property="IsSelectionActive" Value="False" />
</MultiTrigger.Conditions>
<Setter Property="SelectionBrush" Value="{DynamicResource {x:Static SystemColors.InactiveSelectionHighlightBrushKey}}" />
</MultiTrigger>
</Style.Triggers>
</Style>
<Style BasedOn="{StaticResource TextBoxExtStyle}" TargetType="{x:Type local:CustomTextBoxExt}" />
自定义thematicTextBoxExtStyle.xaml。
<Style x:Key="MaterialTextBoxExtStyle" TargetType="{x:Type local:CustomTextBoxExt}">
<Setter Property="FocusVisualStyle" Value="{x:Null}" />
<Setter Property="Foreground" Value="#DD000000" />
<Setter Property="Background" Value="Transparent" />
<Setter Property="BorderBrush" Value="#FF9E9E9E" />
<Setter Property="BorderThickness" Value="0,0,0,1" />
<Setter Property="FontSize" Value="12" />
<Setter Property="FontWeight" Value="Normal" />
<Setter Property="SelectionBrush" Value="#FF0279FF" />
<Setter Property="AllowDrop" Value="true" />
<Setter Property="KeyboardNavigation.TabNavigation" Value="None" />
<Setter Property="HorizontalContentAlignment" Value="Left" />
<Setter Property="VerticalContentAlignment" Value="Center" />
<Setter Property="AllowDrop" Value="true" />
<Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst" />
<Setter Property="Stylus.IsFlicksEnabled" Value="False" />
<Setter Property="CaretBrush" Value="#DD000000" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:CustomTextBoxExt}">
<Grid>
<Border
x:Name="border"
Padding="{TemplateBinding Padding}"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="true">
<ScrollViewer
x:Name="PART_ContentHost"
Background="Transparent"
Focusable="False"
HorizontalScrollBarVisibility="Hidden"
VerticalScrollBarVisibility="Hidden" />
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="border" Property="BorderBrush" Value="#FF757575" />
<Setter TargetName="border" Property="Background" Value="Transparent" />
<Setter Property="Foreground" Value="#DD000000" />
<Setter Property="CaretBrush" Value="#DD000000" />
</Trigger>
<Trigger Property="IsKeyboardFocused" Value="true">
<Setter TargetName="border" Property="BorderBrush" Value="#FF0279FF" />
<Setter Property="BorderThickness" Value="0,0,0,2" />
<Setter Property="Padding" Value="0,0,0,-1" />
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="border" Property="Background" Value="Transparent" />
<Setter TargetName="border" Property="BorderBrush" Value="#FFE0E0E0" />
<Setter Property="Foreground" Value="#60000000" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style BasedOn="{StaticResource MaterialTextBoxExtStyle}" TargetType="{x:Type local:CustomTextBoxExt}" />
并使用附件属性，试图改变默认样式。
public class SkinExt
{
public static string GetTheme(DependencyObject obj)
{
return (string)obj.GetValue(ThemeProperty);
}
public static void SetTheme(DependencyObject obj, string value)
{
obj.SetValue(ThemeProperty, value);
}
// Using a DependencyProperty as the backing store for Theme. This enables animation, styling, binding, etc...
public static readonly DependencyProperty ThemeProperty =
DependencyProperty.RegisterAttached("Theme", typeof(string), typeof(SkinExt), new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.Inherits, new PropertyChangedCallback(OnVisualStyleChanged)));
private static void OnVisualStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
if (e.NewValue != e.OldValue && !string.IsNullOrEmpty(e.NewValue.ToString()) /*&& d is FrameworkElement && (d as FrameworkElement).IsLoaded*/)
{
SkinExt.ApplyTheme(d, e.NewValue.ToString());
}
}
internal static void ApplyTheme(DependencyObject obj, string style)
{
Type itemType = obj.GetType();
List<string> styles = GetDictionaries(obj.GetType().Name.ToString(), style);
if (styles != null && styles.Count > 0)
{
foreach (var path in styles)
{
var rdict = new ResourceDictionary() { Source = new Uri(path, UriKind.RelativeOrAbsolute) };
bool alreadyExist = false;
foreach (var dictionaryFiles in Application.Current.Resources.MergedDictionaries)
{
if (dictionaryFiles.Source.OriginalString.Contains(path))
{
alreadyExist = true;
break;
}
}
if (!alreadyExist)
{
Application.Current.Resources.MergedDictionaries.Add(rdict);
Console.WriteLine(path);
}
}
}
}
internal static List<string> GetDictionaries(String type, string style)
{
List<string> styles = new List<string>();
#region Switch
switch (type)
{
case "CustomTextBoxExt":
styles.Add("/TextBoxExt;component/TextBoxExt/TextBoxExtStyle.xaml");
break;
case "ButtonExt":
styles.Add("/TextBoxExt;component/ButtonExt/ButtonExtStyle.xaml");
break;
case "Label":
styles.Add("/TextBoxExt;component/LabelStyle.xaml");
break;
}
# endregion
return styles;
}
}
设置
local:SkinExt.Theme="Material"
当直接添加子代时，mainwindowgrid中的样式可以正常工作。但是，当使用下面的lazyextension样式时，却无法工作。
public static class LazyLoadExtensions
{
public static LazyUIElementCollection GetLazyChildrens(DependencyObject obj)
{
return (LazyUIElementCollection)obj.GetValue(LazyChildrensProperty);
}
public static void SetLazyChildrens(DependencyObject obj, LazyUIElementCollection value)
{
obj.SetValue(LazyChildrensProperty, value);
}
public static readonly DependencyProperty LazyChildrensProperty =
DependencyProperty.RegisterAttached("LazyChildrens", typeof(LazyUIElementCollection), typeof(LazyLoadExtensions), new PropertyMetadata(OnLazyChildrensChanged));
private static void OnLazyChildrensChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var wrapPanel = d as WrapPanel;
var childrens = LazyLoadExtensions.GetLazyChildrens(wrapPanel);
for (int i = 0; i < childrens.Count; i++)
{
var child = childrens[i];
wrapPanel.Children.Add(child);
}
}
}
public class LazyUIElementCollection : List<UIElement>
{
public LazyUIElementCollection()
{
}
}
工作
<Grid local:SkinExt.Theme="Material">
<WrapPanel x:Name="wrapPanel">
<!--<local:LazyLoadExtensions.LazyChildrens>-->
<!--<local:LazyUIElementCollection>-->
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="MS Label" />
<Label
Width="200"
Height="25"
Content="Material" />
</StackPanel>
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="Custom TextBox" />
<local:CustomTextBoxExt
Width="200"
Height="25"
Text="Material" />
</StackPanel>
<!--</local:LazyUIElementCollection>-->
<!--</local:LazyLoadExtensions.LazyChildrens>-->
</WrapPanel>
</Grid>
不工作
<Grid local:SkinExt.Theme="Material">
<WrapPanel x:Name="wrapPanel">
<local:LazyLoadExtensions.LazyChildrens>
<local:LazyUIElementCollection>
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="MS Label" />
<Label
Width="200"
Height="25"
Content="Material" />
</StackPanel>
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="Custom TextBox" />
<local:CustomTextBoxExt
Width="200"
Height="25"
Text="Material" />
</StackPanel>
</local:LazyUIElementCollection>
</local:LazyLoadExtensions.LazyChildrens>
</WrapPanel>
</Grid>
适用于第二个项目
正确应用第二个自定义文本框ext的样式
<Grid local:SkinExt.Theme="Material">
<WrapPanel x:Name="wrapPanel">
<local:LazyLoadExtensions.LazyChildrens>
<local:LazyUIElementCollection>
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="MS Label" />
<Label
Width="200"
Height="25"
Content="Material" />
</StackPanel>
<StackPanel Margin="10">
<TextBlock Margin="0,0,0,8" Text="Custom TextBox" />
<local:CustomTextBoxExt
Width="200"
Height="25"
Text="Material" />
<local:CustomTextBoxExt
Width="200"
Height="25"
Text="Material" />
</StackPanel>
</local:LazyUIElementCollection>
</local:LazyLoadExtensions.LazyChildrens>
</WrapPanel>
</Grid>
可复制的样本。https:/drive.google.comopen?id=1iB9sY90T7aRaaRTzVc1EvE2qFU13fHG7。
查看上面的样本，并告诉我你的想法。
很酷的项目!
我不太清楚为什么会出现这个问题，但似乎是一个时间问题。
我发现了以下的变通方法：在LazyLoadExtensions中。
private static void OnLazyChildrensChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var wrapPanel = d as WrapPanel;
var childrens = LazyLoadExtensions.GetLazyChildrens(wrapPanel);
for (int i = 0; i < childrens.Count; i++)
{
var child = childrens[i];
//The dictionaries containing the styles are added
SkinExt.SetTheme(child, SkinExt.GetTheme(wrapPanel));
wrapPanel.Children.Add(child);
}
}
这样包含样式的字典就会在添加子代之前被合并，而样式也会被正确应用。
编辑：在LazyLoadExtensions中：这样就可以在添加子代之前合并包含样式的字典，并正确应用样式。 由于你不能改变LazyLoadExtensions类。
在SkinExt类中
internal static void ApplyTheme(DependencyObject obj, string style)
{
Type itemType = obj.GetType();
List<string> styles = GetDictionaries(obj.GetType().Name.ToString(), style);
if (styles != null && styles.Count > 0)
{
foreach (var path in styles)
{
var rdict = new ResourceDictionary() { Source = new Uri(path, UriKind.RelativeOrAbsolute) };
bool alreadyExist = false;
foreach (var dictionaryFiles in Application.Current.Resources.MergedDictionaries)
{
if (dictionaryFiles.Source.OriginalString.Contains(path))
{
alreadyExist = true;
break;
}
}
if (!alreadyExist)
{
Application.Current.Resources.MergedDictionaries.Add(rdict);
if (obj is FrameworkElement frameworkElement && frameworkElement.IsInitialized)
{
//The style won't be applied automaticaly
frameworkElement.Style = rdict.Values.OfType<Style>().First(s => s.TargetType == itemType);
}
else
{
//Nothing to do, style will be applied automaticaly
}
Console.WriteLine(path);
}
}
}
}
如果IsInitialized属性为真，添加的ressourceDictionnary的样式就不会被应用，你可以在调试器中检查。
如果有帮助的话，在dispatcher里面应用主题可以达到预期的效果。
d.Dispatcher.BeginInvoke(new Action(() =>
{
SkinExt.ApplyTheme(d, e.NewValue.ToString());
}));