<mx:TextInput text="{(_feed.url && !_feed.isTemporary)?_feed.url:'Save Feed to generate URL'}"
改成
<mx:TextInput text="{(_feed.url && !_feed.isTemporary)?_feed.url:'Save Feed to generate URL'}" /
<mx:TextInput text="{(_feed.url && !_feed.isTemporary)?_feed.url:'Save Feed to generate URL'}"
<mx:TextInput text="{(_feed.url && !_feed.isTemporary)?_feed.url:'Save Feed to generate URL'}" /