---
source_files:
  - DTS Viewer/DTS.Viewer.Modules/DTS.Viewer.GraphList/Classes/VirtualToggleButton.cs
generated_at: "2026-04-17T15:59:03.091690+00:00"
model: "zai-org/GLM-5-FP8"
schema_version: 1
sha256: "b9f03ca53fe295ee"
---

# VirtualToggleButton Documentation

## 1. Purpose

`VirtualToggleButton` is a static utility class that provides attached dependency properties to imbue any WPF element with toggle button behavior. It allows arbitrary `DependencyObject` instances (specifically those implementing `IInputElement`) to respond to mouse and keyboard input as if they were `ToggleButton` controls, raising the standard `Checked`, `Unchecked`, and `Indeterminate` routed events. This enables toggle-style interactions on elements that cannot inherit from `ToggleButton` directly, such as `TreeViewItem` or custom controls in the `DTS.Viewer.GraphList` module.

---

## 2. Public Interface

### Attached Properties

#### `IsLockedProperty`
```csharp
public static readonly DependencyProperty IsLockedProperty
```
- **Type:** `Nullable<bool>`
- **Default Value:** `false`
- **Metadata Flags:** `BindsTwoWayByDefault | Journal`
- **Description:** Represents the toggle state of the virtual button. When set to `true`, raises `ToggleButton.CheckedEvent`; when `false`, raises `ToggleButton.UncheckedEvent`; when `null`, raises `ToggleButton.IndeterminateEvent`.

#### `IsThreeStateProperty`
```csharp
public static readonly DependencyProperty IsThreeStateProperty
```
- **Type:** `bool`
- **Default Value:** `false`
- **Description:** Determines whether the control supports three states. When `true`, `IsLocked` can cycle through `null` as a third state.

#### `IsVirtualToggleButtonProperty`
```csharp
public static readonly DependencyProperty IsVirtualToggleButtonProperty
```
- **Type:** `bool`
- **Default Value:** `false`
- **Description:** When set to `true` on an element implementing `IInputElement`, attaches mouse and keyboard handlers to enable toggle button behavior.

### Getter/Setter Methods

```csharp
public static Nullable<bool> GetIsLocked(DependencyObject d)
public static void SetIsLocked(DependencyObject d, Nullable<bool> value)

public static bool GetIsThreeState(DependencyObject d)
public static void SetIsThreeState(DependencyObject d, bool value)

public static bool GetIsVirtualToggleButton(DependencyObject d)
public static void SetIsVirtualToggleButton(DependencyObject