DP44/enriched-qwen3-coder-next/Common/DTS.CommonCore/Interface/Viewer.md

---
source_files:
  - Common/DTS.CommonCore/Interface/Viewer/IMainView.cs
  - Common/DTS.CommonCore/Interface/Viewer/IMenuView.cs
  - Common/DTS.CommonCore/Interface/Viewer/IFilterView.cs
  - Common/DTS.CommonCore/Interface/Viewer/INavigationView.cs
  - Common/DTS.CommonCore/Interface/Viewer/ITestDefinitionListView.cs
  - Common/DTS.CommonCore/Interface/Viewer/IMenuViewModel.cs
  - Common/DTS.CommonCore/Interface/Viewer/INavigationViewModel.cs
  - Common/DTS.CommonCore/Interface/Viewer/IFilterViewModel.cs
  - Common/DTS.CommonCore/Interface/Viewer/ITestDefinitionListViewModel.cs
  - Common/DTS.CommonCore/Interface/Viewer/IMainViewModel.cs
generated_at: "2026-04-16T02:22:43.523517+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "d625778ef337fcd6"
---

# Viewer Interface Module Documentation

## 1. Purpose  
This module defines a set of interfaces that establish the contract for the *view* and *view model* layers in a modular UI architecture, specifically for a test definition and analysis application. It establishes a standardized structure for core UI regions—main view, menu, navigation, filter, and test summary list—by defining their corresponding view (`*View`) and view model (`*ViewModel`) interfaces, all inheriting from base interfaces in `DTS.Common.Base`. The module serves as a contract layer enabling decoupled UI composition, likely used in a region-based navigation framework (e.g., Prism), where views and view models are loosely coupled and injected into named regions of a shell application.

## 2. Public Interface  

### View Interfaces (all inherit `IBaseView`):
- **`IMainView`**  
  Represents the main shell/window view. No additional members beyond `IBaseView`.

- **`IMenuView`**  
  Represents the menu view (e.g., top-level menu bar or context menu container). No additional members beyond `IBaseView`.

- **`IFilterView`**  
  Represents the filter/search view (e.g., search bar, filter controls). No additional members beyond `IBaseView`.

- **`INavigationView`**  
  Represents the navigation view (e.g., side navigation panel). No additional members beyond `IBaseView`.

- **`ITestSummaryListView`** *(note: interface name mismatch with file name)*  
  Represents the list view for test definitions/summaries. No additional members beyond `IBaseView`.  
  ⚠️ *File declares `ITestDefinitionListView`, but interface is named `ITestSummaryListView`.*

### View Model Interfaces (all inherit `IBaseViewModel`):
- **`IMenuViewModel`**  
  - `IMenuView View { get; }` — Returns the associated menu view instance.

- **`INavigationViewModel`**  
  - `INavigationView NavigationView { get; }` — Returns the associated navigation view instance.

- **`IFilterViewModel`**  
  - `IBaseView View { get; }` — Returns the associated filter/search view instance.  
  - `IBaseViewModel Parent { get; }` — Reference to the parent view model (likely `IMainViewModel`).  
  - `object ContextSearchRegion { get; set; }` — Holds a reference to the UI region (e.g., content control) where search/filter results are displayed.

- **`ITestSummaryListViewModel`** *(note: interface name mismatch with file name)*  
  - `ITestSummaryListView TestSummaryListView { get; }` — Returns the associated test summary list view.  
  - `ObservableCollection<ITestSummary> TestSummaryList { get; set; }` — Collection of test summaries displayed in the list.  
  - `List<ITestSummary> SelectedTestSummaryList { get; set; }` — Currently selected test summaries.  
  - `void PublishSelectedTestSummaryList()` — Triggers publication of the selected list (e.g., for downstream processing or event broadcasting).

- **`IMainViewModel`**  
  - `IBaseView View { get; }` — Returns the main shell view instance.  
  - `object ContextNavigationRegion { get; set; }` — Reference to the navigation region container.  
  - `object ContextGraphRegion { get; set; }` — Reference to the primary graph region container.  
  - `object ContextTestsRegion { get; set; }` — Reference to the tests region container.  
  - `object ContextGraphsRegion { get; set; }` — Reference to the graphs region container (plural).  
  - `object ContextLegendRegion { get; set; }` — Reference to the legend region container.  
  - `object ContextDiagRegion { get; set; }` — Reference to the diagnostics region container.  
  - `object ContextStatsRegion { get; set; }` — Reference to the statistics region container.  
  - `object ContextCursorRegion { get; set; }` — Reference to the cursor/overlay region container.  
  - `object ContextPropertyRegion { get; set; }` — Reference to the property inspection region container.  
  - `List<FrameworkElement> GetRegions()` — Returns a list of all region containers as `FrameworkElement` instances.

## 3. Invariants  
- All view interfaces (`*View`) must be implemented by UI controls (e.g., `UserControl`, `Window`) that inherit from `IBaseView`.  
- All view model interfaces (`*ViewModel`) must be implemented by view models that inherit from `IBaseViewModel`.  
- Each view model *must* expose a reference to its corresponding view via the `View`-typed property (e.g., `INavigationViewModel.NavigationView`, `IFilterViewModel.View`).  
- `IFilterViewModel` requires a `Parent` reference, implying a hierarchical view model structure.  
- `IMainViewModel` defines a fixed set of named region contexts (`Context*Region`)—these are expected to be non-null after initialization and must correspond to actual UI regions in the shell.  
- `GetRegions()` must return a list containing *all* region containers, including those not explicitly named (e.g., `Context*Region` properties), to support generic region enumeration.

## 4. Dependencies  
### Dependencies *on* this module:  
- **`DTS.Common.Base`**: All interfaces inherit from `IBaseView` and `IBaseViewModel`, implying this module depends on the base layer for core contracts.  
- **`DTS.Common.Interface.TestDefinition`**: `ITestSummaryListViewModel` references `ITestSummary`, indicating a dependency on the `TestDefinition` sub-namespace (likely defining test metadata models).  
- **`System.Collections.Generic`, `System.Collections.ObjectModel`**: Used for list/collection properties in `ITestSummaryListViewModel`.  
- **`System.Windows`**: `IMainViewModel.GetRegions()` returns `FrameworkElement`, indicating a WPF-specific dependency.

### Dependencies *of* this module:  
- This module is *consumed* by higher-level UI composition layers (e.g., shell application, region managers, or DI containers) that instantiate and wire views/view models.  
- Likely consumed by implementations in `DTS.App.*` or similar application projects.

## 5. Gotchas  
- **Interface name mismatch**:  
  - File `ITestDefinitionListView.cs` declares interface `ITestSummaryListView` (not `ITestDefinitionListView`).  
  - File `ITestDefinitionListViewModel.cs` declares interface `ITestSummaryListViewModel` (not `ITestDefinitionListViewModel`).  
  This may cause confusion during code navigation or refactoring.  
- **Ambiguous region semantics**:  
  `Context*Region` properties are typed as `object`, with no compile-time guarantee of their expected type (e.g., `ContentControl`, `Grid`). Consumers must assume runtime type compatibility.  
- **Missing `INavigationView` vs. `NavigationView` naming**:  
  `INavigationViewModel.NavigationView` returns `INavigationView`, but the interface is named `INavigationView` (not `INavigationView`), which is consistent—but the *region* is named `ContextNavigationRegion`, not `ContextShellRegion`, suggesting potential naming inconsistency with other regions.  
- **No explicit region registration**:  
  The interfaces define region *references* but no mechanism to register or validate region names—consumers must rely on external configuration (e.g., XAML region names matching property names like `ContextTestsRegion`).  
- **`IFilterViewModel.ContextSearchRegion`**:  
  The name `ContextSearchRegion` suggests search-specific behavior, but the interface is named `IFilterView`—this may indicate legacy naming or incomplete refactoring.  
- **No documentation for `GetRegions()` behavior**:  
  It is unclear whether `GetRegions()` includes *only* the explicitly named `Context*Region` properties or also other regions; implementation may vary.  

None identified beyond the above.