service-access.md

Service Access Reference

When to read this: You need to interact with Studio services from a ViewModel -- showing dialogs, detecting features, registering types, or obtaining auth tokens. This table lists every service available through the Services property on DesignPropertiesViewModel.

Cross-references

• ViewModel basics: ../design/viewmodel-basics.md
• Feature flags: feature-flags.md
• Complete example (ViewModel usage): ../examples/complete-example.md

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Service table

All services are obtained via Services.GetService<T>() inside a ViewModel.

Service	How to Access	Purpose
IWorkflowDesignApi	Services.GetService<IWorkflowDesignApi>()	Workflow/project APIs, feature detection via HasFeature()
IBusyService	Services.GetService<IBusyService>()	Show loading indicators during long-running operations
IDialogService	Services.GetService<IDialogService>()	Show dialogs and confirmation prompts to the user
IDesignerCustomTypesService	Services.GetService<IDesignerCustomTypesService>()	Register custom .NET types for use in expressions
IUserDesignContext	Services.GetService<IUserDesignContext>()	Check whether the activity is running in a Solutions context
ISolutionResources	Services.GetService<ISolutionResources>()	Manage and access Solutions resource files
IAccessProvider	Services.GetService<IAccessProvider>()	Obtain auth tokens for external API calls
IViewModelActionCallbackFactory	Services.GetService<IViewModelActionCallbackFactory>()	Create callbacks for link clicks and action buttons

Usage example

protected override void InitializeModel()
{
    base.InitializeModel();

    // Feature detection
    var api = Services.GetService<IWorkflowDesignApi>();
    if (api.HasFeature(DesignFeatureKeys.Settings))
    {
        // Project settings are supported -- configure accordingly
    }

    // Show a loading indicator during async initialization
    var busy = Services.GetService<IBusyService>();
    using (busy.ShowBusy())
    {
        // ... long-running init work ...
    }
}

Notes

• GetService<T>() returns null if the service is not available in the current host. Always null-check when the service may be absent (e.g., ISolutionResources is only present in Solutions-enabled Studio).
• IWorkflowDesignApi.HasFeature() is the primary way to check Studio capabilities at design time. See feature-flags.md for the list of known feature keys.