# Winui Wpf Migration

> Migrate WPF applications to WinUI 3 — namespace replacement (System.Windows → Microsoft.UI.Xaml), control mapping (DataGrid→ListView, WrapPanel→ItemsRepeater, TabControl→TabView), threading (Dispatcher→DispatcherQueue), imaging (System.Drawing→BitmapImage), MVVM conversion to CommunityToolkit.Mvvm, and DynamicResource→ThemeResource. Use when converting WPF code, replacing WPF namespaces, or fixin…

- **Type:** Skill
- **Install:** `agentstack add skill-microsoft-win-dev-skills-winui-wpf-migration`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [microsoft](https://agentstack.voostack.com/s/microsoft)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [microsoft](https://github.com/microsoft)
- **Source:** https://github.com/microsoft/win-dev-skills/tree/main/plugins/winui/skills/winui-wpf-migration

## Install

```sh
agentstack add skill-microsoft-win-dev-skills-winui-wpf-migration
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

### Migration Process

#### Step 1: Audit the WPF Source
Before writing code, inventory WPF-specific APIs:
```powershell
# Find all WPF namespace usage
Select-String -Path (Get-ChildItem -Recurse -Filter "*.cs" | Where-Object { $_.FullName -notlike "*\obj\*" }) -Pattern "System\.Windows\." | Select-Object -Property Filename, LineNumber, Line
```
List: WPF controls used, custom MVVM framework, imaging APIs, threading patterns, Win32 interop.

#### Step 2: Create WinUI 3 Project and Align Namespaces
```powershell
dotnet new winui-mvvm -n 
```
Immediately set `` in `.csproj` to match the WPF namespace. Update `x:Class` in `App.xaml`, `MainWindow.xaml` and their code-behind files. Build to verify before porting any code.

#### Step 3: Replace Namespaces

| WPF | WinUI 3 |
|-----|---------|
| `System.Windows` | `Microsoft.UI.Xaml` |
| `System.Windows.Controls` | `Microsoft.UI.Xaml.Controls` |
| `System.Windows.Media` | `Microsoft.UI.Xaml.Media` |
| `System.Windows.Input` | `Microsoft.UI.Xaml.Input` |
| `System.Windows.Data` | `Microsoft.UI.Xaml.Data` |
| `System.Windows.Threading.Dispatcher` | `Microsoft.UI.Dispatching.DispatcherQueue` |
| `PresentationCore` / `PresentationFramework` | Remove entirely |

#### Step 4: Replace Controls

| WPF Control | WinUI 3 Equivalent |
|------------|-------------------|
| `DataGrid` | `ListView` with Grid column headers |
| `WrapPanel` | `ItemsRepeater` + `UniformGridLayout` |
| `TabControl` | `TabView` |
| `StatusBar` | `Grid` row at bottom with `TextBlock` elements |
| `Menu` / `MenuItem` | `MenuBar` / `MenuBarItem` / `MenuFlyoutItem` |
| `ToolBar` | `CommandBar` |
| `Expander` (custom) | `Expander` (built-in) |

#### Step 5: Replace Threading
```csharp
// WPF
Application.Current.Dispatcher.Invoke(() => { /* UI work */ });

// WinUI 3
dispatcherQueue.TryEnqueue(() => { /* UI work */ });
```
Get via `DispatcherQueue.GetForCurrentThread()`. No `Application.Current.Dispatcher` in WinUI 3.

#### Step 6: Replace Imaging
**Critical:** `PresentationCore.dll` and `System.Windows.Media.Imaging` crash the WinUI XAML compiler. This is an architectural incompatibility — no workaround exists.
- Remove ALL `System.Windows.Media.Imaging` references at migration start
- Replace with `Windows.Graphics.Imaging` (WinRT) or `Microsoft.UI.Xaml.Media.Imaging.BitmapImage`
- Do NOT add `true` — it silently corrupts the build
- If heavy imaging code exists, migrate it early (step 2, not step 7)

#### Step 7: Replace MVVM Framework
Delete custom `ObservableObject`/`RelayCommand`/`DelegateCommand`. Use CommunityToolkit.Mvvm:
- `INotifyPropertyChanged` base → `ObservableObject` with `[ObservableProperty]` partial properties
- Custom `RelayCommand` → `[RelayCommand]` attribute
- `{Binding}` → `{x:Bind Mode=OneWay}`
- `DynamicResource` → `{ThemeResource}`

#### Step 8: Replace Resources
- `.resx` → `.resw` (copy + rename to `Strings\en-us\`)
- `{x:Static}` → `x:Uid` for localized strings
- `Properties.Resources.Key` → `ResourceLoader.GetString("Key")`

### Critical Rules

- ❌ NEVER reference `PresentationCore`, `PresentationFramework`, or `System.Windows.Controls` assemblies
- ❌ NEVER add `true` or `None`
- ❌ NEVER delete `Package.appxmanifest`
- ❌ NEVER overwrite `App.xaml` / `App.xaml.cs` — merge WPF code into the WinUI 3 boilerplate
- ✅ Always use `winapp run` to launch — never run the .exe directly
- ✅ Break migration into file-level tasks — not one massive rewrite

### Post-Migration Validation

```powershell
# Check for remaining WPF references (should return nothing)
Select-String -Path (Get-ChildItem -Recurse -Filter "*.cs" | Where-Object { $_.FullName -notlike "*\obj\*" }) -Pattern "System\.Windows\."

# Verify packaging preserved
Test-Path "Package.appxmanifest"  # should be True

# Build and run
.\BuildAndRun.ps1
```

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [microsoft](https://github.com/microsoft)
- **Source:** [microsoft/win-dev-skills](https://github.com/microsoft/win-dev-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-microsoft-win-dev-skills-winui-wpf-migration
- Seller: https://agentstack.voostack.com/s/microsoft
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.