Understanding MVC, MVP, and MVVM in Android with a Three‑in‑One Demo

The article introduces three common Android architectural patterns—MVC, MVP, and MVVM—by presenting a simple click‑button demo that simulates a time‑consuming task, updates a TextView, and demonstrates how each pattern structures the same functionality.

MVC : The Activity acts as both Controller and part of the View, directly invoking a Model class to perform background work. Key code:

public class MvcMainActivity extends AppCompatActivity {
    TextView greetingTextView;
    Button helloButton;
    Button goodbyeButtonClicked;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_mvcmain);
        greetingTextView = findViewById(R.id.greetingTextView);
        helloButton = findViewById(R.id.helloButton);
        goodbyeButtonClicked = findViewById(R.id.goodbyeButtonClicked);
        helloButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new GreetingGeneratorModel("HelloWorld", greetingTextView).execute();
            }
        });
        goodbyeButtonClicked.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new GreetingGeneratorModel("GoodBye", greetingTextView).execute();
            }
        });
    }
}

public class GreetingGeneratorModel extends AsyncTask
{
    private String baseText;
    private TextView greetingTextView;
    public GreetingGeneratorModel(String baseText, TextView greetingTextView) {
        this.baseText = baseText;
        this.greetingTextView = greetingTextView;
    }
    @Override
    protected Integer doInBackground(Void... params) {
        Thread.sleep(2000);
        return (int) (Math.random() * 100);
    }
    @Override
    protected void onPostExecute(Integer randomInt) {
        if ("HelloWorld".equals(baseText)) {
            greetingTextView.setTextColor(Color.RED);
        } else {
            greetingTextView.setTextColor(Color.BLUE);
        }
        greetingTextView.setText(baseText + randomInt);
    }
}

MVP : Uses the Mosby library. The View interface (HelloWorldView) defines UI actions, the Presenter handles business logic, and the Model remains similar but reports results via a callback. Key snippets:

public interface HelloWorldView extends MvpView {
    void showHello(String greetingText);
    void showGoodbye(String greetingText);
}

public class MvpMainActivity extends MvpActivity
implements HelloWorldView {
    // UI fields omitted for brevity
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_mvpmain);
        // find views …
        helloButton.setOnClickListener(v -> presenter.greetHello());
        goodbyeButtonClicked.setOnClickListener(v -> presenter.greetGoodbye());
    }
    @Override
    public void showHello(String greetingText) {
        greetingTextView.setTextColor(Color.RED);
        greetingTextView.setText(greetingText);
    }
    @Override
    public void showGoodbye(String greetingText) {
        greetingTextView.setTextColor(Color.BLUE);
        greetingTextView.setText(greetingText);
    }
    @Override
    public HelloWorldPresenter createPresenter() {
        return new HelloWorldPresenter();
    }
}

public class HelloWorldPresenter extends MvpBasePresenter
{
    private GreetingGeneratorModel greetingTask;
    public void greetHello() {
        cancelTask();
        greetingTask = new GreetingGeneratorModel("HelloWorld", (text) -> {
            if (isViewAttached()) getView().showHello(text);
        });
        greetingTask.execute();
    }
    public void greetGoodbye() {
        cancelTask();
        greetingTask = new GreetingGeneratorModel("GoodBye", (text) -> {
            if (isViewAttached()) getView().showGoodbye(text);
        });
        greetingTask.execute();
    }
    // cancelTask() and detachView() omitted for brevity
}

MVVM : Relies on Android DataBinding. The layout file starts with a <layout> tag containing <data> that declares a handler object and a data object. The Activity binds these objects, eliminating explicit click listeners. Key snippets:

<layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <variable name="handlers" type="com.example.architecturalpatterndemo.mvvm.MyHandlers" />
        <variable name="greetingGeneratorObj" type="com.example.architecturalpatterndemo.mvvm.GreetingGeneratorObj" />
    </data>
    <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical">
        <TextView android:id="@+id/greetingTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@{greetingGeneratorObj.baseText}" />
        <Button android:id="@+id/helloButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:onClick="@{handlers.onClickHello}" android:text="hello" />
        <Button android:id="@+id/goodbyeButtonClicked" android:layout_width="wrap_content" android:layout_height="wrap_content" android:onClick="@{handlers.onClickGoodbye}" android:text="Good bye" />
    </LinearLayout>
</layout>

public class MvvmMainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ActivityMvvmmainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_mvvmmain);
        GreetingGeneratorObj obj = new GreetingGeneratorObj("");
        binding.setGreetingGeneratorObj(obj);
        binding.setHandlers(new MyHandlers(obj));
    }
}

public class MyHandlers {
    private GreetingGeneratorObj greetingGeneratorObj;
    public MyHandlers(GreetingGeneratorObj obj) { this.greetingGeneratorObj = obj; }
    public void onClickHello(View view) {
        new GreetingGeneratorModel("HelloWorld", greetingGeneratorObj).execute();
    }
    public void onClickGoodbye(View view) {
        new GreetingGeneratorModel("GoodBye", greetingGeneratorObj).execute();
    }
}

The article concludes with a link to the full demo repository (https://github.com/youjinjin/ArchitecturalPatternDemo) and invites readers to explore related Android topics.