dropdown list getting hide

I developed a dropdown (ComboBox) Custom Control using three different controls Label (Which will show the Title), and Image (To show dropdown Image) and a List (To display content of drop down) and packaged as NuGet to use in my actual app.
Now, when I am using this dropdown inside the Stack Layout the List of Dropdown is getting hide below the other control. So to resolve that issue i am currently using dropdown control inside Absolute layout which is working fine but I am feeling its not a standard or good approach, Can someone guide me what will be the best approach to use my custom drop down control without absolute layout so that it will not get hide below any other conntrol