[Android] AAC ViewModel 설정 및 ViewModelProviders.of() deprecated

 

본 글은 AAC의 ViewModel 용 관련 글입니다.

 

 

 

Android ViewModel Scope

 

1. Dependaceise 선언 관련 

 

dependencies {
    def lifecycle_version = "2.0.0"
 
    // ViewModel and LiveData
    implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
    // alternatively - just ViewModel
    implementation "androidx.lifecycle:lifecycle-viewmodel:$lifecycle_version" // For Kotlin use lifecycle-viewmodel-ktx
    // alternatively - just LiveData
    implementation "androidx.lifecycle:lifecycle-livedata:$lifecycle_version"
    // alternatively - Lifecycles only (no ViewModel or LiveData). Some UI
    //     AndroidX libraries use this lightweight import for Lifecycle
    implementation "androidx.lifecycle:lifecycle-runtime:$lifecycle_version"
 
    annotationProcessor "androidx.lifecycle:lifecycle-compiler:$lifecycle_version" // For Kotlin use kapt instead of annotationProcessor
    // alternately - if using Java8, use the following instead of lifecycle-compiler
    implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
 
    // optional - ReactiveStreams support for LiveData
    implementation "androidx.lifecycle:lifecycle-reactivestreams:$lifecycle_version" // For Kotlin use lifecycle-reactivestreams-ktx
 
    // optional - Test helpers for LiveData
    testImplementation "androidx.arch.core:core-testing:$lifecycle_version"
}
 

 

2. 추가시 유의사항

implementation'android.arch.lifecycle:ViewModel:1.1.1' //이 아니라


implementation'android.arch.lifecycle:extensions:1.1.1'  //이쪽으로 추가할 것

==> ViewModel로만 연결하면, ViewModelProviders가 없음 (3번참고)

 

3. ViewModel 초기화 변경사항

  androidx.lifecycle:lifecycle-*:2.2.0-alpha03 부터는 ViewModelProviders.of()로 초기화하던 방식이 deprecated 되었다. (아래 링크 참조)

Lifecycle  |  Android 개발자  |  Android Developers

• ViewModelProviders.of() has been deprecated. You can pass a Fragment or FragmentActivity to the new ViewModelProvider(ViewModelStoreOwner) constructor to achieve the same functionality. (aosp/1009889)

 

먼저, 다음과 같은 커스텀 ViewModel 클래스가 있다고 할 때, (JAVA 방식)

 

import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.ViewModel;
 
public class TestViewModel extends ViewModel {
 
    private MutableLiveData<String> test = new MutableLiveData<>();
 
    public MutableLiveData<String> getTest() {
        return test;
    }
 
    public void setTest(MutableLiveData<String> test) {
        this.test = test;
    }
}
 

 

API 변경전 (JAVA 방식)

 
public class MainActivity extends AppCompatActivity {
 
private TestViewModel viewModel;
 
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_activity);
      
        //Activity에서 호출시 (ViewModelProvider.AndroidViewModelFactory 사용)        
        viewModel = ViewModelProviders.of(this).get(TestViewModel.class);
    }
    
}
 
 

 

 

API 변경후 (JAVA 방식)

public class MainActivity extends AppCompatActivity implements ViewModelStoreOwner{
 
    private ViewModelProvider.AndroidViewModelFactory viewModelFactory; 
    private ViewModelStore viewModelStore = new ViewModelStore();
 
    private TestViewModel viewModel;
 
 
 
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_activity);
      
        if(viewModelFactory == null){            
           viewModelFactory = ViewModelProvider.AndroidViewModelFactory.getInstance(getApplication());
        }
 
        viewModel = new ViewModelProvider(this, viewModelFactory).get(TestViewModel.class);
    }
    
 
 
    @Override
    protected void onDestroy() {
        super.onDestroy();
        viewModelStore.clear();
    }
 
    @NonNull
    @Override
    public ViewModelStore getViewModelStore() {
        return viewModelStore;
    }
 
 
}