Android Databinding BindingAdapter Error

问题

I am using following :

public class BindingAdapter {

@android.databinding.BindingAdapter({"app:eventName", "app:onClick"})
public static void setColorChangeListener(final View view,
                                          final String eventName,
                                          View.OnClickListener newListener) {
    CompositeClickListener c = new CompositeClickListener();
    c.addOnClickListener(newListener);
    View.OnClickListener a = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //Toast.makeText(view.getContext(), eventName, Toast.LENGTH_SHORT).show();
        }
    };
    c.addOnClickListener(a);
    view.setOnClickListener(c);
}
}

here is my layout file

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android">

    <data>
    <import type="android.widget.Toast" />

     <variable
         name="namewa"
         type="String" />

        <variable
            name="namewa2"
            type="String" />
        <!--<variable
            name="banner"
            type="games.kapow.android.ui.view_models.BannerViewModel" />-->
    </data>
<android.support.constraint.ConstraintLayout
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.arjitagarwal.helloworld.MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:eventName="@{namewa}"
        app:onClick= "@{(v) -> Toast.makeText(v.getContext(), namewa, Toast.LENGTH_LONG).show()}"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

</layout>

I am getting this error while building the project :

Error:(33, 25) Cannot find the setter for attribute 'app:onClick' with parameter type lambda on android.widget.Button.

However, if I remove eventName thing from both binding adapter and layout it just works fine.

https://developer.android.com/reference/android/databinding/BindingAdapter.html

The above link does this in same manner. What I am doing wrong?

回答1:

A slight change in the annotation is working for me. By Default requireAll is true.

@BindingAdapter(value = {"eventName", "onClick"}, requireAll = false)
public static void setColorChangeListener(final View view,
                                          final String eventName,
                                          View.OnClickListener newListener) {
    CompositeClickListener c = new CompositeClickListener();
    c.addOnClickListener(newListener);
    View.OnClickListener a = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //Toast.makeText(view.getContext(), eventName, Toast.LENGTH_SHORT).show();
        }
    };
    c.addOnClickListener(a);
    view.setOnClickListener(c);
}

回答2:

Try to change your signature for your Binding method:

BindingAdapter({"eventName", "onClick"})
public static void setColorChangeListener(final View view,
                                          final String eventName,
                                          View.OnClickListener newListener) {
    CompositeClickListener c = new CompositeClickListener();
    c.addOnClickListener(newListener);
    View.OnClickListener a = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //Toast.makeText(view.getContext(), eventName, Toast.LENGTH_SHORT).show();
        }
    };
    c.addOnClickListener(a);
    view.setOnClickListener(c);
}
}

来源：https://stackoverflow.com/questions/43806390/android-databinding-bindingadapter-error

标签

android

android-databinding