---
source_files:
  - DTS Viewer/DTS.Viewer.Reports/DTS.Viewer.PSDReport/View/PSDReportMainView.xaml.cs
  - DTS Viewer/DTS.Viewer.Reports/DTS.Viewer.PSDReport/View/PSDReportMainViewGrid.xaml.cs
generated_at: "2026-04-16T11:03:50.028977+00:00"
model: "zai-org/GLM-5-FP8"
schema_version: 1
sha256: "7e23a726984c27b1"
---

# Documentation: DTS.Viewer.PSDReport Views

## 1. Purpose

This module provides WPF view components for the PSD (Power Spectral Density) Report feature within the DTS Viewer application. It contains two partial classes that serve as code-behind for XAML views: `PSDReportMainView` acts as a minimal container view, while `PSDReportMainViewGrid` manages tab focus behavior in response to graph loading events via Prism's event aggregation system.

---

## 2. Public Interface

### `PSDReportMainView` (class)
**Implements:** `IPSDReportMainView`

**Location:** `DTS.Viewer.PSDReport` namespace

| Member | Signature | Description |
|--------|-----------|-------------|
| Constructor | `public PSDReportMainView()` | Initializes the XAML component. Contains commented-out code for AvalonDock layout serialization. |

---

### `PSDReportMainViewGrid` (class)
**Implements:** `IPSDReportMainViewGrid`

**Location:** `DTS.Viewer.PSDReport` namespace

| Member | Signature | Description |
|--------|-----------|-------------|
| Constructor | `public PSDReportMainViewGrid()` | Initializes the XAML component and attaches a `Loaded` event handler. |
| `_eventAggregator` | `private IEventAggregator` | Backing field for the Prism event aggregator, resolved at runtime. |
| `SetFocus` | `private void SetFocus()` | Selects and focuses the `chartResultsTab` element. |
| `PSDReportMainViewGrid_Loaded` | `private void PSDReportMainViewGrid_Loaded(object sender, RoutedEventArgs e)` | Resolves `IEventAggregator` from the container and subscribes to `GraphLoadedCountNotification` events. |
| `OnGraphLoadedCountNotification` | `private void OnGraphLoadedCountNotification(GraphLoadedCountNotificationArg arg)` | Event handler that waits 3 seconds then sets focus to the chart results tab via `Dispatcher.BeginInvoke`. |

---

## 3. Invariants

- **Container Availability:** `PSDReportMainViewGrid` requires `ContainerLocator.Container` to be properly initialized before the `Loaded` event fires, otherwise `_eventAggregator` will be null.
- **DataContext Type:** The `DataContext` of `PSDReportMainViewGrid` must be castable to `IBaseViewModel` for the event filtering logic in `OnGraphLoadedCountNotification` to function correctly.
- **XAML Element Existence:** The `chartResultsTab` element (referenced in `SetFocus()`) must be defined in the associated XAML file.
- **Event Matching:** The `OnGraphLoadedCountNotification` handler only executes its focus logic when `arg.ParentVM` matches the view's `DataContext` (after casting to `IBaseViewModel`).

---

## 4. Dependencies

### This module depends on:
- `DTS.Common.Interface` — Provides `IPSDReportMainView`, `IPSDReportMainViewGrid`, and `IBaseViewModel`
- `DTS.Common.Base` — Referenced but specific types not visible in code-behind
- `DTS.Common.Events` — Provides `GraphLoadedCountNotification` event and `GraphLoadedCountNotificationArg`
- `Prism.Ioc` — Provides `ContainerLocator` for service resolution
- `Prism.Events` — Provides `IEventAggregator` for pub/sub messaging
- `System` — `Action` delegate
- `System.Threading` — `Thread.Sleep`
- `System.Threading.Tasks` — `Task.Run`

### What depends on this module:
- Not determinable from the provided source files alone. Consumers would be modules that instantiate `IPSDReportMainView` or `IPSDReportMainViewGrid` (likely via dependency injection or navigation).

---

## 5. Gotchas

1. **Hardcoded 3-Second Delay:** The `OnGraphLoadedCountNotification` method uses `Thread.Sleep(TimeSpan.FromSeconds(3))` before setting focus. This is a magic number with no configuration or explanation—likely a workaround for timing issues with graph rendering completion.

2. **Commented-Out AvalonDock Code:** `PSDReportMainView` contains significant commented-out code for layout serialization using `XmlLayoutSerializer` and a file path `.\DataProViewerAvalonDock.config`. This suggests dock panel persistence was previously implemented but intentionally disabled.

3. **Late Event Subscription:** Per the comment "FB 14797", the event subscription occurs in the `Loaded` event handler rather than the constructor. This means any `GraphLoadedCountNotification` events fired before the view is fully loaded will be missed.

4. **Silent Failure on Container Resolution:** The `_eventAggregator?.GetEvent<...>()` call uses a null-conditional operator. If `ContainerLocator.Container.Resolve<IEventAggregator>()` returns null, the subscription silently fails with no logging or error handling.

5. **Dispatcher Threading:** The focus operation is marshaled to the UI thread via `Dispatcher.BeginInvoke`, but the 3-second sleep runs on a background thread via `Task.Run`. This is intentional but could be a source of race conditions if the view is unloaded during the wait period.