WPF is a powerful technology for building modern desktop applications. But developing a robust user interface with WPF often involves a lot of work, especially when it comes to managing window docking and layout. Fortunately, there's a solution to this problem – AvalonDock.

AvalonDock is a free, open-source library that provides advanced window docking and layout capabilities to WPF applications. With AvalonDock, you can easily create complex layouts with multiple windows that can be docked, floated, and resized at runtime. In this article, we will explore the capabilities of AvalonDock and learn how to use it in our own WPF applications.

Getting Started with AvalonDock

To get started with AvalonDock, you first need to download and install the library. You can do this by either downloading the source code from the Github repository or by using the NuGet package manager. Once you have installed AvalonDock, you need to add a reference to it in your WPF project.

The next step is to create a layout for your application. AvalonDock provides a control called DockingManager, which serves as the root element for your layout. You can add other controls such as tabs, panels, and documents within the DockingManager to create your desired layout.

For example, let's say we want to create a layout with two panels: one for displaying a tree view and one for displaying a document. We can start by defining the DockingManager control in our XAML file:

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Next, we can add two panels to the layout. The first panel will contain a TreeView control, and the second panel will contain a TextBlock control. We can use the DocumentPane and AnchorablePane controls to achieve this:

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When we run the application, we will see two panels docked side by side with the tree view on the left and the document on the right. We can then resize, float, and dock these panels at runtime, providing a highly customizable user interface to our users.

Customizing the Appearance of AvalonDock

AvalonDock provides a highly customizable appearance, allowing you to style its controls to match the style of your application. The styling capabilities of AvalonDock are based on WPF's style and control templates.

For example, let's say we want to change the appearance of the document tabs in our layout. We can do this by defining a custom style for the LayoutDocument control:

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In this example, we define a custom style for the LayoutDocumentTabItem control, which is responsible for displaying the tabs of our document panes. We set the background, foreground, and font weight properties to customize the appearance of the tabs, and we provide a custom control template to change the layout of the tab content.

With this custom style in place, the tabs in our application will have a light gray background, black text, and bold font weight.

Managing Layout at Runtime

One of the most powerful features of AvalonDock is its ability to manage layout at runtime. This means that your users can customize their layout by resizing, floating, and docking panels as they see fit. AvalonDock provides a number of API methods and events to help you manage layout at runtime.

For example, let's say we want to programmatically add a new anchorable panel to our layout when the user clicks a button. We can do this by handling the Click event of the button and creating a new instance of the LayoutAnchorable control and adding it to the AnchorablePane control:

```

private void AddAnchorablePanelButton_Click(object sender, RoutedEventArgs e)

{

var newPanel = new LayoutAnchorable();

newPanel.Title = "New Panel";

newPanel.Content = new TextBlock() { Text = "This is my new panel!" };

DockingManager.Layout.RootPanel.Children.Add(newPanel);

}

```

In this example, we create a new instance of LayoutAnchorable, set its title and content properties, and add it to the root panel of the DockingManager control. When we run the application and click the "Add Panel" button, a new panel will appear in the layout.

Conclusion

AvalonDock is a powerful library for adding window docking and layout capabilities to your WPF applications. With its advanced features and highly customizable appearance, AvalonDock provides a flexible and user-friendly user interface that can be customized to meet the needs of any application.

In this article, we explored the basics of using AvalonDock in a WPF application, including creating a layout, customizing appearance, and managing layout at runtime. With these tools at your disposal, you can create robust and customizable desktop applications that meet the needs of even the most demanding users.