TypeError: Error #1034: Type Coercion failed: cannot convert XMLList@37ace21 to Class.

Problem:

Something is receiving the wrong data type and it cannot be converted. For example, a function is expecting a string and we pass it an Array.

This also occurred in when I was passing an Array to a function that expected another data type.
The error detail is “cannot convert []@e1f73f9 mx.core.IUIComponent.”

NOTICE – The value I am passing to the “target” property is an Array because the value is enclosed in brackets “[myvalue]”. This would work if the property was “targets”. The property “target” expects an object.

// INCORRECT


// CORRECT - Notice I removed the Array brackets

In this next example, an XMLList cannot be converted into an Array, which is what this component needs.

The error details is “cannot convert XMLList@37ace21 to Class.”

 
public function tabBarHandler(event:ItemClickEvent):void {
    
	var menuitems:XML = event.item.menuitems as XML;

	// this converts an xml list into a array collection but the tab bar cannot accept an xmllist data type
	// you *CAN* use this method if your data provider can accept an ArrayCollection
	//var menuDP:ArrayCollection = new ArrayCollection(new XMLListCollection(event.item.menuitems.submenu as XMLList).toArray());

	// in our case since we *CANNOT* we manually convert it to an array and then add it to the tabbar
	for each (var menuitem:XML in menuitems.submenu) {

		// create a new object and assign the properties to it from the xml node
		var newItem:Object = new Object();
		newItem.label = menuitem.@label;
		newItem.link = menuitem.@link;
		// optionally create a reference to the original xmlnode
		newItem.menuitem = menuitem;
		// add item to the array collection
		menuDP.addItem(newItem);

		trace(menuitem.@label);

	}

	// add new menuDP array collection to our tab bar
	subMenuBar.dataProvider = menuDP;
}

Please reply in the comments below if this helped you or not. You can also use the Error Lookup Tool to look up Flex compiler or runtime errors. more info…