winforms-themes

This project adds support for themes in .NET WinForms applications. This project supports both out-of-the-box and custom themes and uses our winforms-stylable-controls project to style controls which are lacking style support.

License

ToC

• WinForms Themes
  • License
  • Development
  • Usage
  • Extended Usage
  • Contributions

Development

Test Coverage

First, install the reportgenerator tool:

dotnet tool install -g dotnet-reportgenerator-globaltool

Next, build a debug version of the project:

dotnet build WinFormsThemes/WinFormsThemes.sln -c Debug

The test coverage report can then be created using:

rmdir /s /q WinFormsThemes\TestProject\TestResults
dotnet test WinFormsThemes/TestProject --no-build --verbosity normal --collect:"XPlat Code Coverage"
reportgenerator -reports:WinFormsThemes\TestProject\TestResults\*\coverage.cobertura.xml -targetdir:WinFormsThemes\TestProject\TestResults\html -reporttypes:Html -sourcedirs:WinFormsThemes\WinFormsThemes
start "" WinFormsThemes\TestProject\TestResults\html\index.html

Mutation testing

We use Stryker.NET for mutation testing. To run the mutation tests, use:

dotnet tool restore
dotnet stryker

Important: Do not start stryker in the project directory - you need to start it in the solution dir, otherwise the config will not be found!

Usage

To use this project, you need to add a reference to our nuget package (dotnet add package AssortedDevelopment.WinFormsThemes) first.

Note: Currently, this project requires .NET 6.0 or higher.

Next, you need to configure the themes:

var registry = ThemeRegistryHolder.GetBuilder().Build();
var theme = registry.ThemeRegistry.GetTheme();

This can, for example, be placed in the Program.cs of your application and uses the default settings to lookup the themes, return the registry and use its standard theme.

At last, you need to provide the theme to all forms to be themed and add a single line in the Load event:

theme.Apply(this);

This will apply this theme on the given Form and all children.

Extended Usage

Of course, you can extend this library and customize the handling to fit your needs. Here are a few examples:

Logging

If you want to debug an issue with this library, you can enable logging in the IThemeRegistryBuilder:

ThemeRegistryHolder.GetBuilder().SetLoggerFactory(LoggerFactory).Build();

This will log all actions of the library to the given ILoggerFactory.

Note: Any calls before calling SetLoggerFactory will not be affected so we advise to call SetLoggerFactory as early as possible.

Making IThemeRegistry and ITheme globally available

When you do not have a dependency injection available in your project, we provide utilities to make both IThemeRegistry and ITheme globally available:

1. IThemeRegistry For the IThemeRegistry, we provide the ThemeRegistryHolder class which can be used to store the registry and retrieve it later:

ThemeRegistryHolder.ThemeRegistry = ThemeRegistryHolder.GetBuilder().Build();

After this, you can retrieve the registry from anywhere in your application using: var registry = ThemeRegistryHolder.ThemeRegistry;

2. ITheme For the ITheme, the IThemeRegistry provides a Current property which can be used to retrieve the current theme. For this to work though, you need to configure a selector that defines the current theme:

private ITheme SelectCurrentTheme(IThemeRegistry registry)
{
	//logic to select theme here
}
...
ThemeRegistryHolder.ThemeRegistry =  ThemeRegistryHolder.GetBuilder().WithCurrentThemeSelector(SelectCurrentTheme).Build();

This enables you to use IThemeRegistry.Current to retrieve the current theme and IThemeRegistry.OnThemeChanged to be notified of changes:

var mytheme = ThemeRegistryHolder.ThemeRegistry.Current;
ThemeRegistryHolder.ThemeRegistry.OnThemeChanged += (sender, args) =>
{
	//logic to handle theme change here
};

Customize theme selection

By default, our library will honor the settings of the operating system in regard to dark mode and high contrast when calling GetTheme. If you want to add additional selection criteria or you want to give the user an option to override this selection you can do that easily. Instead of relying on the default settings in IThemeRegistry.GetTheme() you can set IThemeRegistry.Current to any theme you want by providing a CurrentThemeSelector:

IThemeRegistry registry = ThemeRegistryHolder.GetBuilder()
                .WithCurrentThemeSelector(registry => registry.GetTheme())
				.Build();
var selectedTheme = registry.CurrentTheme;

Add custom themes

Out of the box, there are 2 ways you can add custom themes:

• Files with the file ending .theme.json stored in a themes directory of the working dir.
• Assembly resources in any assembly where the name starts with CONFIG_THEMING_THEME_

Both ways use the same JSON format for the theme definition(the version defines the format of the file). A simple example of this could be:

{
    "name": "theme-name",
    "capabilities": ["DarkMode", "HighContrast"],
    "version": 3,
    "variables": {
        "backColor": "#082a56",
        "foreColor": "#082a57"
    },
    "colors": {
        "backColor": "backColor",
        "foreColor": "foreColor",
        "controls": {
            "backColor": "backColor",
            "foreColor": "foreColor"
        }
    }
}

For the complete list of available settings please check our JSON schema here.

If those 2 ways are not flexible enough, you can implement a theme by yourself and register it using a custom theme source (see below): The prefered way is to subclass AbstractTheme as you just need to implement the base colors and optionally override the extended colors - styling the controls is done by the base class.

The more advanced way is implementing the ITheme interface. This only supports the basic infrastructure like theme capabilities but the styling is completely in your hands.

The views can be added by either implementing an IThemeLookup (see below) or by adding it directly to the builder:

ThemeRegistryHolder.GetBuilder()
    .WithThemes()
        .AddDefaultThemes()
        .AddTheme(new MySuperDarkTheme())
        .FinishThemeList()
    .Build();

Add custom theme source

If you want to add another theme source besides files and resources (e.g. when implementing custom ITheme or AbstractTheme implementations) or you just want to change the folder path, you can add a custom IThemeLookup implementation which handles the search for available themes:

    internal class MyThemeLookup : IThemeLookup
    {
        public int Order => 999; //highest order wins when 2 lookups return the same theme name

        public List<ITheme> Lookup()
        {
            List<ITheme> results = new List<ITheme>();
            //implement search for themes here
            return results;
        }
    }
}

After this, you need to register this class in the builder:

 ThemeRegistryHolder.GetBuilder()
     .WithThemes()
         .AddDefaultThemes()
         .WithLookup()
         .FinishThemeList()
     .Build();

Add third-party controls theme support

As we do not want to force you to use a specific WinForms control library, we currently only support styling of standard controls and controls from our winforms-stylable-controls project. As we understand you may want to also style other controls, we support adding specialised plugins to handle styling of a specific type of control. To do this, you need to implement ``:

    internal class MyCustomControlThemePlugin : AbstractThemePlugin<MyCustomControl>
    {
        protected override void ApplyPlugin(MyCustomControl mcc, AbstractTheme theme)
        {
            //style control based on the colors available in the Theme
        }
    }

At last, you just need to register it for the correct type:

 ThemeRegistryHolder.GetBuilder()
     .AddThemePlugin(new MyCustomControlThemePlugin())
     .Build();

Note: Currently, we only support directly registered types. Subclasses will not be styled automatically!

Contributions

Please view the contributing guide for more information.