如何将Enum对象添加到Android Bundle中?


当前回答

我知道这是一个老问题,但我也遇到了同样的问题,我想分享一下我是如何解决它的。关键是Miguel所说的:枚举是可序列化的。

给定以下enum:

enum YourEnumType {
    ENUM_KEY_1, 
    ENUM_KEY_2
}

Put:

Bundle args = new Bundle();
args.putSerializable("arg", YourEnumType.ENUM_KEY_1);

其他回答

我创建了一个Koltin扩展:

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) )
}

创建一个bundle并添加:

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

并获得:

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

我认为将enum转换为int(对于普通enum),然后设置在bundle上是最简单的方法。就像下面的代码:

myIntent.PutExtra("Side", (int)PageType.Fornt);

然后检查状态:

int type = Intent.GetIntExtra("Side",-1);
if(type == (int)PageType.Fornt)
{
    //To Do
}

但并不适用于所有枚举类型!

一种简单的方法,将整数值赋给enum

示例如下:

public enum MyEnum {

    TYPE_ONE(1), TYPE_TWO(2), TYPE_THREE(3);

    private int value;

    MyEnum(int value) {
        this.value = value;
    }

    public int getValue() {
        return value;
    }

}

发件人页面:

Intent nextIntent = new Intent(CurrentActivity.this, NextActivity.class);
nextIntent.putExtra("key_type", MyEnum.TYPE_ONE.getValue());
startActivity(nextIntent);

接收端:

Bundle mExtras = getIntent().getExtras();
int mType = 0;
if (mExtras != null) {
    mType = mExtras.getInt("key_type", 0);
}

/* OR
    Intent mIntent = getIntent();
    int mType = mIntent.getIntExtra("key_type", 0);
*/

if(mType == MyEnum.TYPE_ONE.getValue())
    Toast.makeText(NextActivity.this, "TypeOne", Toast.LENGTH_SHORT).show();
else if(mType == MyEnum.TYPE_TWO.getValue())
    Toast.makeText(NextActivity.this, "TypeTwo", Toast.LENGTH_SHORT).show();
else if(mType == MyEnum.TYPE_THREE.getValue())
    Toast.makeText(NextActivity.this, "TypeThree", Toast.LENGTH_SHORT).show();
else
    Toast.makeText(NextActivity.this, "Wrong Key", Toast.LENGTH_SHORT).show();

enum YourEnum { 类型1, 类型2 }

传递bundle as bundleOf("TYPE" to youenum . type1)

收到, 参数?。let {it.getSerializable(B"TYPE") as YourEnum}

有一点需要注意,如果你使用bundle。将一个Bundle添加到通知中,你可能会遇到以下问题:

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

...

要解决这个问题,你可以做以下事情:

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);
        }
    }
}

然后可以这样使用:

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

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