WPF和MVVM-动态更改主题 [英] WPF and MVVM - changing themes dynamically
问题描述
我正在使用MVVM进行WPF项目，并且正在尝试实现可动态更改主题的功能.主题信息位于单独的xaml文件(即Theme1.xaml，Theme2.xaml)中.由于各种原因，我想在ViewModel类中而不是在View.xaml文件后面的代码中进行实际的主题更改.
I'm working on a WPF project using MVVM and I'm trying to implement a feature that changes the theme dynamically. The theming info is located in separate xaml files (ie Theme1.xaml, Theme2.xaml). I want to do the actual theme changing in the ViewModel class rather than in the code behind file of View.xaml for various reasons.
我尝试了几个主意，但什么也没用:
I've tried a couple ideas but can't get anything to work:
-
我尝试将View的ResourceDictionary绑定到ViewModel中的变量，但被告知无法在ResourceDictionary类型的Source属性上设置绑定
I tried binding the ResourceDictionary of View to a variable in ViewModel but am told that a binding cannot be set on the Source property of type ResourceDictionary
我的ViewModel类中没有任何可调用"UpdateTheme"方法的View对象
I don't have any sort of View object in my ViewModel class on which to call a "UpdateTheme" method
关于如何从ViewModel类更改View类中的MergedDictionary引用的任何想法?
Any ideas on how I can change the MergedDictionary reference in my View class from the ViewModel class?
谢谢！
推荐答案
我在前面已经解决了同一时间问题，在此情况下我所做的可能是它可以为您提供帮助.
I have worked with the same time problem earlier here what i did in my case may be it can help you out.
将所有主题文件(theme1.xaml，theme2.xaml ...)复制到exe路径下的Themes文件夹中.并尝试使用以下示例代码.使用绑定
Copy all you theme files (theme1.xaml, theme2.xaml...) into Themes folder at you exe path. and try with below sample code. using Bindings
public partial class MainWindow : Window, INotifyPropertyChanged
{
private FileInfo _SelectTheme;
public FileInfo SelectedTheme
{
get { return _SelectTheme; }
set
{
_SelectTheme = value;
OnChanged("SelectedTheme");
ChangeTheme(_SelectTheme);
}
}
private void ChangeTheme(FileInfo _SelectTheme)
{
App.Current.Resources.Clear();
App.Current.Resources.Source = new Uri(_SelectTheme.FullName, UriKind.Absolute);
}
private ObservableCollection<FileInfo> _files;
public ObservableCollection<FileInfo> Files
{
get { return _files; }
set { _files = value; OnChanged("Files"); }
}
public MainWindow()
{
this.InitializeComponent();
Dispatcher.BeginInvoke(DispatcherPriority.Background, new Action(() =>
{
var localthemes = new System.IO.DirectoryInfo("Themes").GetFiles();
if (Files == null)
Files = new ObservableCollection<FileInfo>();
foreach (var item in localthemes)
{
Files.Add(item);
}
SelectedTheme = Files[0];
}));
this.DataContext = this;
}
public event PropertyChangedEventHandler PropertyChanged;
public void OnChanged(string name)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
<Window x:Class="WPFTheme.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Name="Window"
Title="MainWindow"
Width="640"
Height="480">
<Grid x:Name="LayoutRoot" Background="{DynamicResource DisabledForegroundBrush}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="0.285*" />
<ColumnDefinition Width="0.365*" />
<ColumnDefinition Width="0.35*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="0.132*" />
<RowDefinition Height="0.162*" />
<RowDefinition Height="0.403*" />
<RowDefinition Height="0.168*" />
<RowDefinition Height="0.135*" />
</Grid.RowDefinitions>
<Button Width="57"
Margin="15,13,0,10.872"
HorizontalAlignment="Left"
Content="Enabled" />
<Button Width="72"
Margin="0,14,17.12,10.872"
HorizontalAlignment="Right"
Content="Disabled"
IsEnabled="False" />
<TextBlock Grid.Column="1"
Width="69"
Margin="11.88,15,0,27.872"
HorizontalAlignment="Left"
Text="TextBlock"
TextWrapping="Wrap" />
<TextBox Grid.Column="1"
Width="64"
Height="21"
Margin="9.88,0,0,4.872"
HorizontalAlignment="Left"
VerticalAlignment="Bottom"
Text="TextBox"
TextWrapping="Wrap" />
<TextBox Grid.Column="1"
Height="21"
Margin="88.88,0,35.8,3.872"
VerticalAlignment="Bottom"
IsEnabled="False"
Text="TextBox Disabled"
TextWrapping="Wrap" />
<CheckBox Grid.Row="1"
Width="71"
Height="14"
Margin="11,7.128,0,0"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Content="CheckBox" />
<CheckBox Grid.Row="1"
Width="71"
Height="14"
Margin="0,8.128,15.12,0"
HorizontalAlignment="Right"
VerticalAlignment="Top"
Content="Disabled"
IsEnabled="False" />
<ComboBox Grid.Column="2"
Width="94"
Margin="8.2,18,0,11.872"
HorizontalAlignment="Left"
ItemsSource="{Binding Files}"
SelectedItem="{Binding SelectedTheme,
Mode=TwoWay,
UpdateSourceTrigger=PropertyChanged}" />
<ComboBox Grid.Column="2"
Width="94"
Margin="0,17,14,12.872"
HorizontalAlignment="Right"
IsEnabled="False"
ItemsSource="{Binding Files}" />
<DataGrid Grid.Row="2"
Grid.Column="1"
Margin="8.88,6.876,7.8,62.862"
AutoGenerateColumns="True"
ItemsSource="{Binding Files}" />
<DatePicker Grid.Row="2"
Height="23"
Margin="10,0,15,147"
VerticalAlignment="Bottom" />
<GroupBox Grid.Row="2"
Grid.Column="2"
Margin="6.2,2.876,6,5.862"
Header="GroupBox">
<ScrollViewer Margin="6,0.723,1,1" ScrollViewer.HorizontalScrollBarVisibility="Visible">
<ListBox Width="161"
Height="108"
ItemsSource="{Binding Files}" />
</ScrollViewer>
</GroupBox>
<ListView Grid.Row="2"
Grid.Column="1"
Height="59"
Margin="12.88,0,5.8,-4.138"
VerticalAlignment="Bottom"
ItemsSource="{Binding Files}">
<ListView.View>
<GridView>
<GridViewColumn Header="File Name">
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}" />
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
<ProgressBar x:Name="progressBar"
Grid.Row="1"
Grid.Column="1"
Height="20"
Margin="5.88,6.128,61.8,0"
VerticalAlignment="Top"
Value="50" />
<RadioButton Grid.Row="1"
Width="64"
Margin="11,25.128,0,29.124"
HorizontalAlignment="Left"
Content="RadioButton" />
<RadioButton Grid.Row="1"
Width="51"
Margin="0,25.128,33.12,29.124"
HorizontalAlignment="Right"
Content="RadioButton"
IsEnabled="False" />
<Slider Grid.Row="1"
Grid.Column="1"
Margin="11.88,34.128,38.8,15.124"
AutoToolTipPlacement="BottomRight"
Maximum="{Binding Maximum,
ElementName=progressBar}"
Minimum="{Binding Minimum,
ElementName=progressBar}"
Value="{Binding Value,
ElementName=progressBar}" />
<TabControl Grid.Row="1"
Grid.Column="2"
Margin="7.2,9.128,9,0.124">
<TabItem Header="TabItem">
<Grid Background="#FFE5E5E5" />
</TabItem>
<TabItem Header="TabItem">
<Grid Background="#FFE5E5E5" />
</TabItem>
</TabControl>
<TreeView Grid.Row="3"
Margin="8,5.138,12.12,1.79"
ItemsSource="{Binding Files}" />
<ToolBar Grid.Row="4"
Grid.ColumnSpan="2"
Margin="10,9.21,104.8,17">
<Button />
<CheckBox />
<ComboBoxItem />
<MenuItem />
<Separator />
<TabItem />
</ToolBar>
</Grid>
</Window>
这篇关于WPF和MVVM-动态更改主题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
