Realm+kotlin android RealmMigrationNeededException—Field count is more than expected

Realm 2.1.1 + kotlin 1.1.3 environment.

The exception "RealmMigrationNeedException: Field count is more than expected" always occurs during maigration.

Before migration

public open class TestObject():RealmObject(){
@PrimaryKey
open var name: String=""
open range: Int=0
}

After migration

public open class TestObject():RealmObject(){
@PrimaryKey
open var name: String=""
open range: Int=0
open var hogehoge: String=""// Add
}

migrationObject

class MyMigration:RealmMigration {

override fun migrate(realm:DynamicRealm?, oldVersion:Long, newVersion:Long) {
    Log.i ("", "oldVersion $oldVersion newVersion $newVersion")
    var oldVersion = oldVersion

    val schema=realm!!.schema

    if(oldVersion==0L){
        vara = schema.get ("TestObject")
        a.addField("hogehoge", String::class.java, FieldAttribute.REQUIRED)
        oldVersion++
    }
}
}

application maigration portion

Realm.init(this)
    val builder=RealmConfiguration.Builder()
    builder.schemaVersion(1L).migration(MyMigration())
    val config = builder.build()
    Realm.setDefaultConfiguration(config)

Where the error occurred
MainActivity

 override fun onCreate (savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    Fabric.with (this, Crashlytics(), CrashlyticsNdk());
    setContentView(R.layout.activity_start)

    Log.i ("mainActivity", "startMainActivity")
    val realm=Realm.getDefaultInstance()// Error Occurred

Error Contents

Cause by:io.realm.exception.RealmMigrationNeededException: Field count is more than expected-expected2 but was 3
atio.realm.TestObjectRealmProxy.validateTable (TestObjectRealmProxy.java:182)
atio.realm.DefaultRealmModuleMediator.validateTable (DefaultRealmModuleMediator.java:186)
atio.realm.Realm.initializeRealm(Realm.java:344)
atio.realm.Realm.createAndValidate (Realm.java:301)
atio.realm.Realm.createInstance(Realm.java:280)
atio.realm.RealmCache.createRealmOrGetFromCache (RealmCache.java:143)
atio.realm.Realm.getDefaultInstance(Realm.java:211)
at jp.co.ftaba_d.bluebear.MainActivity.onCreate(MainActivity.kt:103)

It always happens regardless of object type.
I would appreciate it if someone could teach me.

android realm kotlin

2022-09-30 16:10

1 Answers

The defined model does not have @Required annotation, so FieldAttribute.REQUIRED is not required to add fields in the migration class. github.com/realm/realm-java/issues/4701 is considering automatically @Required if the model is non-nullable.

If you feel it is not reflected after modifying the model class, try cleaning the project.
Disabling incremental builds by specifying kotlin.incremental=false in build.gradle may also work.

2022-09-30 16:10

If you have any answers or tips

Popular Tags

python x 4647

android x 1593

java x 1494

javascript x 1427

c x 927

c++ x 878

ruby-on-rails x 696

php x 692

python3 x 685

html x 656