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Editor to share with you what should be paid attention to when using the FlexaddChild () method. I hope you will get something after reading this article. Let's discuss it together.

Considerations for the FlexaddChild () method

In FlexApplication, it is not possible to add classes from flash.display packages such as Sprite,MovieClip directly with FlexaddChild.

For example, the following code will report an error:

Privatefunctioninit (): void {varsp:Sprite=newSprite (); addChild (sp);}

The code is as follows:

TypeError:Error#1034: cast type failed: unable to convert flash.display::Sprite@156b7b1 to mx.core.IUIComponent.

This is because the FlexaddChild method of Application is not completely inherited from DisplayObjectContainer

Application → LayoutContainer → Container → UIComponent → FlexSprite → Sprite → DisplayObjectContainer

It was rewritten in Container:

The code is as follows:

PublicoverridefunctionaddChild (child:DisplayObject): DisplayObject

Although the parameter child is of type DisplayObject, it must implement the IUIComponent interface (which all Flex components implement) before it can be added.

If you want to add a Sprite to Application, you can first install it into a UIComponent, and then add the UIComponent:

Example:

The code is as follows:

Importmx.core.UIComponent;privatefunctioninit (): void {varsp:Sprite=newSprite (); varuc:UIComponent=newUIComponent (); uc.addChild (sp); addChild (uc);} after reading this article, I believe you have some understanding of "what should be paid attention to when using the FlexaddChild () method". If you want to know more about it, welcome to follow the industry information channel, thank you for reading!

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