Navigation Data Bindings

NavigationDataBindings.java

package com.example.cain.mvvmexample;


import android.content.Intent;
import android.databinding.BindingAdapter;
import android.databinding.InverseBindingAdapter;
import android.databinding.InverseBindingListener;
import android.support.annotation.Nullable;
import android.view.View;

public class ViewBindings {

    @BindingAdapter(value = {"navRequest", "navRequestAttrChanged"}, requireAll = false)
    public static void setNavRequest(View view, @Nullable NavigationRequest navRequest, @Nullable InverseBindingListener inverseBindingListener) {
        if (navRequest != null) {
            Intent intent = navRequest.getIntent(view.getContext());
            view.getContext().startActivity(intent);
            if (inverseBindingListener != null) {
                inverseBindingListener.onChange();
            }
        }
    }

    @InverseBindingAdapter(attribute = "navRequest")
    public static NavigationRequest getNavRequest(View view) {
        return null; // clear nav request
    }

}

NavigationRequest.java

package com.example.cain.mvvmexample;


import android.content.Context;
import android.content.Intent;

public interface NavigationRequest {

    Intent getIntent(Context context);

}

OtherScreenRequest.java

package com.example.cain.mvvmexample;


import android.content.Context;
import android.content.Intent;

public class OtherScreenRequest implements NavigationRequest {
    
    public final String EXTRA_ID = "id";
    private final int id;
    public OtherScreenRequest(int id) {
        this.id = id;
    }
    
    @Override
    public Intent getIntent(Context context) {
        Intent intent = new Intent(context, OtherScreenActivity.class);
        intent.putExtra(EXTRA_ID, id);
        return intent;
    }

}