Argthtjtr

I bind a List of Interfaces with a type argument via databinding.

Interface:

public interface MyInterface<T> {



    T getValue();



}

ViewModel:

public class MyViewModel {



    public ObservableField<List<MyInterface>> name = new ObservableField<>();



}

BindingAdapter:

@android.databinding.BindingAdapter("bind")

public static void bind(TextView textView, List<MyInterface> list) {    

}

XML:

<data>



    <variable

            name="viewModel"

            type="com.example.myname.playground4.MyViewModel"/>



</data>





<TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        app:bind="@{viewModel.name}"

        app:layout_constraintBottom_toBottomOf="parent"

        app:layout_constraintLeft_toLeftOf="parent"

        app:layout_constraintRight_toRightOf="parent"

        app:layout_constraintTop_toTopOf="parent"/>

This works as long as the ViewModel is in Java.

When I convert the ViewModel to Kotlin:

class MyKotlinViewModel {

    val name = ObservableField<List<MyInterface<*>>>()

}

I get an error in my ActivityMainBindingImpl.java:

error: incompatible types: Object cannot be converted to List

Here's the faulty method:

@Override

protected void executeBindings() {

    long dirtyFlags = 0;

    synchronized(this) {

        dirtyFlags = mDirtyFlags;

        mDirtyFlags = 0;

    }

    android.databinding.ObservableField viewModelName = null;

    java.util.List viewModelNameGet = null;

    com.example.fweigl.playground4.MyKotlinViewModel viewModel = mViewModel;



    if ((dirtyFlags & 0x7L) != 0) {







            if (viewModel != null) {

                // read viewModel.name

                viewModelName = viewModel.getName();

            }

            updateRegistration(0, viewModelName);





            if (viewModelName != null) {

                // read viewModel.name.get()

                viewModelNameGet = viewModelName.get(); // error is here

            }

    }

    // batch finished

    if ((dirtyFlags & 0x7L) != 0) {

        // api target 1



        com.example.fweigl.playground4.BindingAdapter.bind(this.mboundView0, viewModelNameGet);

    }

}

Anyone know the reason for this and / or how to fix this?

You can try for yourself with my test project @ https://github.com/fmweigl/playground4. The (working) java version is on branch 'master', the (non-working) kotlin version on branch 'kotlin'.

I think that your problem is about your BindingAdapter.In Kotlin you have to add @JvmStatic annotation to top of your BindingAdapter.

Like this:

@JvmStatic

@BindingAdapter("bind")

fun bind(recyclerView: RecyclerView, items: MutableList<SmartResult>) {

     //Anything that you wanna do ...

}

Because when your ViewModel an XML want to use of your binding adapter it has to be static like in java!