Make getViewModelClass optional

Author: Juraj Novák

library/src/main/java/eu/inloop/viewmodel/ProxyViewHelper.java

@@ -10,7 +10,7 @@
 import java.lang.reflect.Proxy;
 import java.lang.reflect.Type;
 
-class ProxyViewHelper {
+public class ProxyViewHelper {
 
     private static final class ProxyDummyClass {
     }
@@ -29,7 +29,7 @@ static <T> T init(@NonNull Class<?> in) {
     }
 
     @Nullable
-    static Class<?> getGenericType(@NonNull Class<?> in, @NonNull Class<?> whichExtends) {
+    public static Class<?> getGenericType(@NonNull Class<?> in, @NonNull Class<?> whichExtends) {
         final Type genericSuperclass = in.getGenericSuperclass();
         if (genericSuperclass instanceof ParameterizedType) {
             final Type[] typeArgs = ((ParameterizedType) genericSuperclass).getActualTypeArguments();

library/src/main/java/eu/inloop/viewmodel/base/ViewModelBaseActivity.java

@@ -7,6 +7,7 @@
 
 import eu.inloop.viewmodel.AbstractViewModel;
 import eu.inloop.viewmodel.IView;
+import eu.inloop.viewmodel.ProxyViewHelper;
 import eu.inloop.viewmodel.ViewModelHelper;
 import eu.inloop.viewmodel.binding.ViewModelBindingConfig;
 
@@ -19,7 +20,14 @@ public abstract class ViewModelBaseActivity<T extends IView, R extends AbstractV
     @Override
     protected void onCreate(@Nullable final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        mViewModeHelper.onCreate(this, savedInstanceState, getViewModelClass(), getIntent().getExtras());
+        
+        Class<? extends AbstractViewModel<T>> viewModelClass = getViewModelClass();
+        // try to extract the ViewModel class from the implementation
+        if (viewModelClass == null) {
+            //noinspection unchecked
+            viewModelClass = (Class<? extends AbstractViewModel<T>>) ProxyViewHelper.getGenericType(getClass(), AbstractViewModel.class);
+        }
+        mViewModeHelper.onCreate(this, savedInstanceState, viewModelClass, getIntent().getExtras());
     }
 
     /**
@@ -32,7 +40,9 @@ public void setModelView(@NonNull final T view) {
     }
 
     @Nullable
-    public abstract Class<R> getViewModelClass();
+    public Class<R> getViewModelClass() {
+        return null;
+    }
 
     @CallSuper
     @Override

library/src/main/java/eu/inloop/viewmodel/base/ViewModelBaseFragment.java

@@ -9,6 +9,7 @@
 
 import eu.inloop.viewmodel.AbstractViewModel;
 import eu.inloop.viewmodel.IView;
+import eu.inloop.viewmodel.ProxyViewHelper;
 import eu.inloop.viewmodel.ViewModelHelper;
 import eu.inloop.viewmodel.binding.ViewModelBindingConfig;
 
@@ -21,7 +22,14 @@ public abstract class ViewModelBaseFragment<T extends IView, R extends AbstractV
     @Override
     public void onCreate(@Nullable final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        getViewModelHelper().onCreate(getActivity(), savedInstanceState, getViewModelClass(), getArguments());
+
+        Class<? extends AbstractViewModel<T>> viewModelClass = getViewModelClass();
+        // try to extract the ViewModel class from the implementation
+        if (viewModelClass == null) {
+            //noinspection unchecked
+            viewModelClass = (Class<? extends AbstractViewModel<T>>) ProxyViewHelper.getGenericType(getClass(), AbstractViewModel.class);
+        }
+        getViewModelHelper().onCreate(getActivity(), savedInstanceState, viewModelClass, getArguments());
     }
 
     @CallSuper
@@ -60,7 +68,9 @@ public void onDestroy() {
     }
 
     @Nullable
-    public abstract Class<R> getViewModelClass();
+    public Class<R> getViewModelClass() {
+        return null;
+    }
 
     /**
      * @see ViewModelHelper#getViewModel()