Implementing attached behavior to reuse UI logic

Attached properties are useful for encapsulating simple reusable logic or assigning information to a UI element. However, because attached properties are implemented in static classes, they do not retain state, which may be necessary for advanced usage scenarios. One powerful technique to address this is by using attached behavior.

Here are a few examples where you could create a custom attached behavior and reuse it for multiple elements:

• Creating custom editor validation rules
• Implementing drag-and-drop logic
• Implementing image zooming
• Handling any UI-related events when you wish to keep code-behind clean

Getting ready

To follow the steps described in this recipe, we just need to create a blank .NET MAUI application.

The code for this recipe is available at https://github.com/PacktPublishing/.NET-MAUI-Cookbook/tree/main/Chapter03/c3-AttachedBehavior.

How to do it…

Let’s create...