How to Apply Windows 10 Dark and Light Themes to Your Delphi VCL App
If you want to give your Delphi VCL app a modern and elegant look, you can use the built-in VCL styles that match the Windows 10 dark and light themes. In this article, we will show you how to check the Windows theme mode and apply the appropriate VCL style to your app.
Windows 10 IDE Dark,Light VCL Style Theme for Delphi Rio
To check whether the Windows theme mode is dark or light, you need to access the registry key Computer\\HKEY_CURRENT_USER\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize and read the value of AppsUseLightTheme. If the value is 1, then the Windows theme mode is light; if the value is 0, then the Windows theme mode is dark.
You can use the TRegistry class from the System.Win.Registry unit to read and write registry values. Here is an example of a function that returns true if the Windows theme mode is light and false otherwise:
function IsWindowsThemeLight: Boolean;
Reg := TRegistry.Create;
Reg.RootKey := HKEY_CURRENT_USER;
if Reg.OpenKeyReadOnly('\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize') then
Result := Reg.ReadInteger('AppsUseLightTheme') = 1
Result := True; // default to light theme if key not found
Applying the VCL Style
To apply a VCL style to your app, you need to include it in your project options. Go to Project -> Options -> Appearance and select the available styles that you want to use. For example, you can select Windows10 Dark and Windows10 styles for dark and light themes respectively.
Then, you need to use the TStyleManager class from the Vcl.Themes unit to set the active style at runtime. You can do this in the OnCreate event of your main form or in any other suitable place. Here is an example of how to set the appropriate style based on the Windows theme mode:
procedure TForm1.FormCreate(Sender: TObject);
if IsWindowsThemeLight then
Now, when you run your app, it will automatically adapt to the Windows theme mode and use the corresponding VCL style.
In this article, we have shown you how to apply Windows 10 dark and light themes to your Delphi VCL app using VCL styles. This way, you can give your app a modern and elegant look that matches the user's preference. You can also explore other VCL styles that are available in Delphi Rio and customize them according to your needs.
Using Styles from GetIt and DelphiStyles.com
If you want to use more VCL styles than the ones included in Delphi Rio, you can download additional styles from GetIt or from DelphiStyles.com. GetIt is a package manager that allows you to install libraries, components, and styles directly from the IDE. DelphiStyles.com is a website that offers premium VCL styles for various themes and platforms.
To use a style from GetIt, go to Tools -> GetIt Package Manager and search for \"VCL Style\". You will see a list of available styles that you can install by clicking the Install button. After installing a style, you need to add it to your project options and then use the TStyleManager class to set it as the active style.
To use a style from DelphiStyles.com, you need to purchase a subscription and download the style files. Then, you need to copy the style files to your project folder or to a common folder that you can access from your projects. After that, you need to add the style files to your project options and then use the TStyleManager class to set them as the active style.
Creating and Customizing Styles with the Bitmap Style Designer Tool
If you want to create your own VCL style or customize an existing one, you can use the Bitmap Style Designer tool that comes with Delphi Rio. The Bitmap Style Designer is a graphical tool that allows you to edit the appearance of various user interface elements, such as buttons, menus, scroll bars, etc.
To launch the Bitmap Style Designer, go to Tools -> Bitmap Style Designer. You can create a new style from scratch or open an existing style file (.vsf). You can also import a style from a FireMonkey style file (.style) or from a Windows theme file (.msstyles). Once you have opened or created a style, you can use the Object Inspector and the Preview pane to modify its properties and see the results.
To save your style, go to File -> Save As and choose a name and location for your style file (.vsf). Then, you need to add the style file to your project options and then use the TStyleManager class to set it as the active style. 29c81ba772