Set control Background color using Dynamic Resource in WPF?

Question

This is my XAML

<Grid.Resources>             <SolidColorBrush x:Key="DynamicBG"/> </Grid.Resources> <Label name="MyLabel" Content="Hello" Background="{DynamicResource DynamicBG} /> 

So I have two questions:

Q1: How do I go about setting the DynamicBG key value to Red in my code now? (When the window loads, I'd like to set it to red)

Q2: Is this how dynamic resources are supposed to be used?

Thank you

Answer 1

To gain access to the Resource of the code must identify them in the file App.xaml:

<Application.Resources>     <SolidColorBrush x:Key="DynamicBG" /> </Application.Resources> 

XAML example

<Grid>            <Label Name="MyLabel"             Content="Hello"             Background="{DynamicResource DynamicBG}" />      <Button Content="Change color"             Width="100"              Height="30"              Click="Button_Click" /> </Grid> 

The Resource can be changed in code line of the form:

Application.Current.Resources["MyResource"] = MyNewValue; 

Example:

Code behind

// using ContentRendered event private void Window_ContentRendered(object sender, EventArgs e) {     SolidColorBrush MyBrush = Brushes.Aquamarine;      // Set the value     Application.Current.Resources["DynamicBG"] = MyBrush;          }  private void Button_Click(object sender, RoutedEventArgs e) {     SolidColorBrush MyBrush = Brushes.CadetBlue;      // Set the value     Application.Current.Resources["DynamicBG"] = MyBrush; } 

Principle, DynamicResources were designed, so they can be changed. Where to change - it is the task of the developer. In the case of Color, it is one of the most common methods. See the MSDN, for more information.

P. S. I recommend using App.xaml, because there have been cases where a StaticResource has been used successfully, but not DynamicResource (resources are placed in the Window.Resources). But after moving the resource in App.xaml, everything started to work.