Data Binding onClick not working

Question

I am getting started for using DataBinding and something is wrong with my onClick.

GameViewModel.java

public void onClickItem(int row, int col){
    Log.d("click","row: "+row+" col: "+col);
}
@BindingAdapter("load_image")
public static void loadImage(ImageView view,int imageId) {
    view.setImageResource(getDrawable(imageId));
}

GameFragment.java

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    //View view=inflater.inflate(R.layout.fragment_game, container, false);
    FragmentGameBinding binding = DataBindingUtil.inflate(inflater, R.layout.fragment_game, container, false);
    View view = binding.getRoot();
    ButterKnife.bind(this,view);
    binding.setGameViewModel(gameViewModel);
    gameViewModel= ViewModelProviders.of(getActivity()).get(GameViewModel.class);
    gameViewModel.init();
return view;
}

fragment_game.xml

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

tools:context=".view.GameFragment">

<data>
     <import type="android.support.v4.app.Fragment"/>
    <import type="android.view.View"/>

    <variable
        name="gameViewModel"
        type="harkor.addus.viewmodel.GameViewModel" />
</data>


<android.support.constraint.ConstraintLayout
   (...)>

    <TextView
        (...)>

    <android.support.constraint.ConstraintLayout
        (...)>

        <ImageView
            android:id="@+id/image_puzzle11"
            android:src="@android:color/holo_green_dark"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_marginEnd="1dp"
            android:layout_marginRight="1dp"
            android:onClick="@{() -> gameViewModel.onClickItem(1,1)}"
            app:load_image="@{0}"
            app:layout_constraintBottom_toTopOf="@+id/image_puzzle21"
            app:layout_constraintDimensionRatio="w,1:1"
            app:layout_constraintEnd_toStartOf="@+id/image_puzzle12"
            app:layout_constraintHorizontal_bias="0.5"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />
(...)

load_image is working, but onClick do nothing... No error in compilation, no crash when button is clicking on device, no result in console...

Answer 1

Please check with below code:

You have written as to call on Click of image as :

 android:onClick="@{() -> gameViewModel.onClickItem(1,1)}"

Try to write as below and check again :

android:onClick="@{(v) -> gameViewModel.onClickItem(1,1)}"

As per the Guidance This is not the way to achieve the Architecture Principles we can work as below as per the MVVM Architecture: 1. Create an Interface 2. Define Interface as handler inside the Layout File as :

<variable
        name="handler"
        type="com.cityguide.interfaces.MustVisitItemListener"></variable>

3.Now we are using this handler to define onclick as :

android:onClick="@{(v) ->handler.onGalleryItemClick(v,currentPosition,photo)}"

4. Implement the Handler with our java Class or Activity class before bind the Handler with View as below:

private MustVisitItemListener mItemListener;

mItemListener = new MustVisitItemListener() { };

5.Set the Interface handler with bind object as below:

mbinding.setHandler(mItemListener);