Android MVVM Design Pattern Examples

Question

I currently do a lot of WPF development and have started creating some basic Android apps. When creating WPF apps I often use MVVM, normally using Prism, and would like to k

Answer 1

You can follow these steps for DataBinding in Fragments: I have posted design and java class both in Example for Binding Data in Fragment.

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:bind="http://schemas.android.com/apk/res-auto">
    <data class=".UserBinding">
        <variable  name="user" type="com.darxstudios.databind.example.User"/>
    </data>
 <RelativeLayout

    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivityFragment"
    >



        <TextView android:text='@{user.firstName+"  "+user.lastName}' android:layout_width="wrap_content"
        android:layout_height="wrap_content"
            android:id="@+id/textView" />

     <Button
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="New Button"
         android:id="@+id/button"
         android:layout_below="@+id/textView"
         android:layout_toEndOf="@+id/textView"
         android:layout_marginStart="40dp"
         android:layout_marginTop="160dp" />

 </RelativeLayout>
</layout>


    public class MainActivityFragment extends Fragment {

    public MainActivityFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        final User user = new User();
        user.setFirstName("Michael");
        user.setLastName("Cameron");
        UserBinding binding = DataBindingUtil.inflate(inflater,R.layout.fragment_main, container, false);
        binding.setUser(user);

        View view = binding.getRoot();

        final Button button = (Button) view.findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                user.setFirstName("@Darx");
                user.setLastName("Val");
            }
        });

        return view;
    }

}

Developer site DataBinding Guide Line

Answer 2

A few years ago I also do some WPF&WP development，Prism & MVVM Light Toolkit is commonly use to build WP App,it is perfect for windows phone application architecture I think ! so I use my previous experience of WP development then imitate to create Android MVVM Light Toolkit(A toolkit help to build Android MVVM Application，We have more attributes for Data Binding of View(like Uri for ImageView) ,we create some command for deal with event( like click of Button),also have a global message pipe to communicate with other ViewModel).

GitHub:Android MVVM Light Toolkit, there are samples for reference.

Architecture： http://upload-images.jianshu.io/upload_images/966283-78b410b9af8b18fa.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240

hope to help you!