更新MutableLiveData对象的AndroidViewModel

public class MyViewModel extends AndroidViewModel {
    private MutableLiveData<String> data;

    public MyViewModel(Application application) {
        super(application);
        data = new MutableLiveData<>();
    }

    public MutableLiveData<String> getData() {
        return data;
    }

    public void updateData(String newData) {
        data.setValue(newData);
    }
}

public class MyActivity extends AppCompatActivity {
    private MyViewModel viewModel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);

        viewModel = ViewModelProviders.of(this).get(MyViewModel.class);
        viewModel.getData().observe(this, new Observer<String>() {
            @Override
            public void onChanged(String newData) {
                // 处理数据变化
            }
        });
    }

    private void updateData() {
        viewModel.updateData("New data");
    }
}