Android: How to put an Enum in a Bundle?

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How do you add an Enum object to an Android Bundle?

13 Answers

It may be better to pass it as string from myEnumValue.name() and restore it from YourEnums.valueOf(s), as otherwise the enum's ordering must be preserved!

Longer explanation: Convert from enum ordinal to enum type

In Kotlin:

enum class MyEnum {
  NAME, SURNAME, GENDER
}

Put this enum in a Bundle:

Bundle().apply {
  putInt(MY_ENUM_KEY, MyEnum.ordinal)
}

Get enum from Bundle:

val ordinal = getInt(MY_ENUM_KEY, 0)
MyEnum.values()[ordinal]

Full example:

class MyFragment : Fragment() {

    enum class MyEnum {
        NAME, SURNAME, GENDER
    }

    companion object {
        private const val MY_ENUM_KEY = "my_enum_key"

        fun newInstance(myEnum: MyEnum) = MyFragment().apply {
            arguments = Bundle().apply {
                putInt(MY_ENUM_KEY, myEnum.ordinal)
            }
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        with(requireArguments()) {
            val ordinal = getInt(MY_ENUM_KEY, 0)
            val myEnum = MyEnum.values()[ordinal]
        }
    }
}

In Java:

public final class MyFragment extends Fragment {
    private static final String MY_ENUM_KEY = "my_enum";

    public enum MyEnum {
        NAME,
        SURNAME,
        GENDER
    }

    public final MyFragment newInstance(MyEnum myEnum) {
        Bundle bundle = new Bundle();
        bundle.putInt(MY_ENUM_KEY, myEnum.ordinal());
        MyFragment fragment = new MyFragment();
        fragment.setArguments(bundle);
        return fragment;
    }

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bundle arguments = this.requireArguments();
        int ordinal = arguments.getInt(MY_ENUM_KEY, 0);
        MyEnum myEnum = MyEnum.values()[ordinal];
    }
}

I've created a Koltin extension:

fun Bundle.putEnum(key: String, enum: Enum<*>) {
    this.putString( key , enum.name )
}

inline fun <reified T: Enum<T>> Intent.getEnumExtra(key:String) : T {
    return enumValueOf( getStringExtra(key) )
}

Create a bundle and add:

Bundle().also {
   it.putEnum( "KEY" , ENUM_CLAS.ITEM )
}

and get:

intent?.getEnumExtra< ENUM_CLAS >( "KEY" )?.let{}

For Intent you can use this way:

Intent : kotlin

FirstActivity :

val intent = Intent(context, SecondActivity::class.java)
intent.putExtra("type", typeEnum.A)
startActivity(intent)

SecondActivity:

override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState) 
     //...
     val type = (intent.extras?.get("type") as? typeEnum.Type?)
}

One thing to be aware of -- if you are using bundle.putSerializable for a Bundle to be added to a notification, you could run into the following issue:

*** Uncaught remote exception!  (Exceptions are not yet supported across processes.)
    java.lang.RuntimeException: Parcelable encountered ClassNotFoundException reading a Serializable object.

...

To get around this, you can do the following:

public enum MyEnum {
    TYPE_0(0),
    TYPE_1(1),
    TYPE_2(2);

    private final int code;

    private MyEnum(int code) {
        this.code = navigationOptionLabelResId;
    }

    public int getCode() {
        return code;
    }

    public static MyEnum fromCode(int code) {
        switch(code) {
            case 0:
                return TYPE_0;
            case 1:
                return TYPE_1;
            case 2:
                return TYPE_2;
            default:
                throw new RuntimeException(
                    "Illegal TYPE_0: " + code);
        }
    }
}

Which can then be used like so:

// Put
Bundle bundle = new Bundle();
bundle.putInt("key", MyEnum.TYPE_0.getCode());

// Get 
MyEnum myEnum = MyEnum.fromCode(bundle.getInt("key"));
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