> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/gum/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/gum/code/gum-code-reference/graphicaluielement/parentchanged.md).

# ParentChanged

## Introduction

The ParentChanged event is invoked whenever an object's direct parent is changed. This can happen when any of the following occur:

1. The Parent property is assigned to a null or non-null value
2. An object is added to a parent's Children collection
3. An object is added to root
4. A Forms object creates and adds a child Forms object

## Code Example: Handling Parent Changed

The following code raises the ParentChanged event when children are added to a parent using a variety of methods:

```csharp
// Initialize
var child= new ContainerRuntime();
child.ParentChanged += (_,_) => System.Diagnostics.Debug.WriteLine("parent changed");

var parent = new ContainerRuntime();

// the following code raises the event 4 times
parent.Children.Add(child);
parent.Children.Remove(child);

child.Parent = parent;
child.Parent = null;
```


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