Languages

This page is also available in 简体中文 and 日本語.

Diagnostics reference

Compiler diagnostics are defined in Prism.SourceGenerators/Diagnostics/DiagnosticDescriptors.cs on master. Titles below match the descriptor title; see the compiler message for parameterised text.

Help link

Descriptors point at the product README diagnostics section; this page is the preferred human index.

PSG0001–PSG0004 — partial requirements

ID	Severity	Title
PSG0001	Error	Class with [ObservableProperty] members must be partial
PSG0002	Error	Class with command generation attribute must be partial
PSG0003	Error	Property with [ObservableProperty] must be partial
PSG0004	Error	Class with [BindableBase] must be partial
PSG0005	Error	Class with [BindableValidator] must be partial
PSG0006	Error	[BindableValidator] is only supported on classes

Code fix: MakePartial is available for PSG0001–PSG0005 in the IDE (Ctrl+. / Alt+Enter).

PSG1001–PSG1002 — command signatures

ID	Severity	Title
PSG1001	Error	Invalid [DelegateCommand] method signature
PSG1002	Error	Invalid [AsyncDelegateCommand] method signature

See DelegateCommand and AsyncDelegateCommand.

PSG2001–PSG2006 — names, handlers, signatures

ID	Severity	Title
PSG2001	Warning	Catch handler not found
PSG2002	Warning	Catch handler has incompatible signature
PSG2003	Warning	CanExecute member not found
PSG2004	Warning	Observed property not found
PSG2005	Warning	[NotifyCanExecuteChangedFor] command not found
PSG2006	Warning	CanExecute member has incompatible signature

PSG3002 — AsyncDelegateCommand package

ID	Severity	Title
PSG3002	Error	AsyncDelegateCommand package required for Prism prior to 9.0

Install MvvmAIO.Prism.SourceGenerators and, on Prism.Core 8.1.97, MvvmAIO.Prism.Bcl.Commands, or upgrade to Prism 9+.

PSG4001–PSG4002 — container registration

ID	Severity	Title
PSG4001	Warning	ServiceType is not assignable from implementation type
PSG4002	Warning	ViewModelType could not be resolved

See Container registration.

PSG5001 — validation

ID	Severity	Title
PSG5001	Warning	[NotifyDataErrorInfo] requires BindableValidator base type

[NotifyDataErrorInfo] is only effective when the containing type inherits from BindableValidator or is annotated with [BindableValidator]. Without it the generated setter will not call ValidateProperty. See BindableValidator.

PSG6001 — partial property suggestion

ID	Severity	Title
PSG6001	Info	Use partial property for [ObservableProperty] (C# 13+)

Code fix: Convert field-backed [ObservableProperty] to a partial property when C# 13+ is enabled.

PSG0007–PSG0008 — Navigation & dialog awareness

ID	Severity	Title
PSG0007	Error	Class with [NavigationAware] must be partial
PSG0008	Error	Class with [DialogAware] must be partial

Code fix: MakePartial is available in the IDE.

See NavigationAware and DialogAware.

PSG7001–PSG7005 — region navigation commands

ID	Severity	Title
PSG7001	Error	IRegionManager member not found
PSG7002	Error	Region is required for [NavigateCommand]
PSG7003	Error	Target is required for [NavigateCommand]
PSG7004	Error	[NavigateOnChanged] requires [ObservableProperty]
PSG7005	Error	TargetMember is required for [NavigateOnChanged]

See NavigateCommand.

PSG7101–PSG7102 — dialog service commands

ID	Severity	Title
PSG7101	Error	IDialogService member not found
PSG7102	Error	Name is required for [ShowDialogCommand]

See ShowDialogCommand.

PSG7006–PSG7008 — [FromNavigationParameter]

ID	Severity	Title
PSG7006	Error	[FromNavigationParameter] can only be applied to fields or properties
PSG7007	Warning	[FromNavigationParameter] requires [ObservableProperty]
PSG7008	Error	[FromNavigationParameter] key cannot be empty

See NavigationAware.

PSG7103–PSG7105 — [FromDialogParameter]

ID	Severity	Title
PSG7103	Error	[FromDialogParameter] can only be applied to fields or properties
PSG7104	Warning	[FromDialogParameter] requires [ObservableProperty]
PSG7105	Error	[FromDialogParameter] key cannot be empty

See DialogAware.

Next

• Generators overview
• Contributing