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Android Android Fragments Introducing Fragments Handling Clicks

Posted by Tarek M.Tolba
Tarek M.Tolba
Courses Plus Student 3,613 Points

interface (Fragements)

Can someone please explain what does this line of code do or why did we use it?

onRecipeSelectedInterface listener = (onRecipeSelectedInterface) getActivity();

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

We need to get a handle on the listener interface so we can call it when needed. Since the interface is implemented in the Activity, we use getActivity() to get a reference to it. However the value getActivity() returns is not of type onRecipeSelectedInterface. Its type is a general Activity, not the specific MainActivity (or whatever the activity class is named here) that implements onRecipeSelectedInterface. So we need to explicitly downcast it with the (onRecipeSelectedInterface) part to make the types match.