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Android

Posted by Vladimir Gleba
Vladimir Gleba
1,337 Points

Why do I need to "Moosh" var like this: intVar + ""; instead of just cast in as a string like this: (String) intVar?

For me, "mooshing" seams like a bad programming. And assuming that we already learn how to cast variables, why do we need to "moosh" them? And also, why its is even possible, why it is not an error?

1 Answer

Seth Kroger
Seth Kroger
56,416 Points

There are other ways to do it, but not by casting. Casting will only work between types that are the same branch of the inheritance tree (either by extends or implements). Strings and primitive numbers aren't. When you use string concatenation with a piece that isn't a String Java will automatically call a method called toString() on it to turn in into one.

If fact, one of the other ways to do it is to just call toString() directly. With int variables you would write Integer.toString(intVar) in place of IntVar + "".

Vladimir Gleba
Vladimir Gleba
1,337 Points

I see. I already tried to do this in the code (cast as string) and Android Studio fixed it to the toString() solution. So it was very helpful for me to understand why. Thank you!

Vladimir Gleba
Vladimir Gleba
1,337 Points

The only thing... It is still strange. The compiler always throws an error when you try to save one type of var into another. Even if it's obvious and the Studio suggest only one solution to fix it. But at the same time it allows you to mix types during the concatenation. It's just strange..