Create ViewAction1 to weakly refer to views.

src/main/java/rx/functions/ViewAction1.java

@@ -0,0 +1,53 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx.android.functions;
+
+import android.view.View;
+
+import rx.functions.Action1;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * An {@link Action1} implementation specific for {@link View}s.
+ *
+ * @param <V> the type of {@link View} upon which to perform the action.
+ * @param <T> the type being observed
+ */
+public abstract class ViewAction1<V extends View, T> implements Action1<T> {
+
+    private final WeakReference<V> viewReference;
+
+    public ViewAction1(V view) {
+        viewReference = new WeakReference<V>(view);
+    }
+
+    @Override
+    public final void call(T t) {
+        V view = viewReference.get();
+        if (view != null) {
+            call(view, t);
+        }
+    }
+
+    /**
+     * Implement this instead of {@link Action1#call(Object)}.
+     * @param view the view given in the constructor.
+     * @param t the object being observed
+     */
+    public abstract void call(V view, T t);
+
+}

src/main/java/rx/functions/ViewActionSetActivated.java

@@ -17,18 +17,14 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
-
-public class ViewActionSetActivated implements Action1<Boolean> {
-
-    private final View view;
+public class ViewActionSetActivated extends ViewAction1<View, Boolean> {
 
     public ViewActionSetActivated(View view) {
-        this.view = view;
+        super(view);
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         view.setActivated(aBoolean);
     }
 }

src/main/java/rx/functions/ViewActionSetClickable.java

@@ -17,18 +17,14 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
-
-public class ViewActionSetClickable implements Action1<Boolean> {
-
-    private final View view;
+public class ViewActionSetClickable extends ViewAction1<View, Boolean> {
 
     public ViewActionSetClickable(View view) {
-        this.view = view;
+        super(view);
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         view.setClickable(aBoolean);
     }
 }

src/main/java/rx/functions/ViewActionSetEnabled.java

@@ -17,18 +17,14 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
-
-public class ViewActionSetEnabled implements Action1<Boolean> {
-
-    private final View view;
+public class ViewActionSetEnabled extends ViewAction1<View, Boolean> {
 
     public ViewActionSetEnabled(View view) {
-        this.view = view;
+        super(view);
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         view.setEnabled(aBoolean);
     }
 }

src/main/java/rx/functions/ViewActionSetFocusable.java

@@ -17,18 +17,14 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
-
-public class ViewActionSetFocusable implements Action1<Boolean> {
-
-    private final View view;
+public class ViewActionSetFocusable extends ViewAction1<View, Boolean> {
 
     public ViewActionSetFocusable(View view) {
-        this.view = view;
+        super(view);
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         view.setFocusable(aBoolean);
     }
 }

src/main/java/rx/functions/ViewActionSetSelected.java

@@ -17,18 +17,14 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
-
-public class ViewActionSetSelected implements Action1<Boolean> {
-
-    private final View view;
+public class ViewActionSetSelected extends ViewAction1<View, Boolean> {
 
     public ViewActionSetSelected(View view) {
-        this.view = view;
+        super(view);
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         view.setSelected(aBoolean);
     }
 }

src/main/java/rx/functions/ViewActionSetVisibility.java

@@ -17,30 +17,27 @@
 
 import android.view.View;
 
-import rx.functions.Action1;
+public class ViewActionSetVisibility extends ViewAction1<View, Boolean> {
 
-public class ViewActionSetVisibility implements Action1<Boolean> {
-
-    private final View view;
     private final int visibilityOnFalse;
 
     public ViewActionSetVisibility(View view) {
         this(view, View.GONE);
     }
 
     public ViewActionSetVisibility(View view, int visibilityOnFalse) {
+        super(view);
         if (visibilityOnFalse != View.GONE &&
                 visibilityOnFalse != View.INVISIBLE &&
                 visibilityOnFalse != View.VISIBLE) {
             throw new IllegalArgumentException(visibilityOnFalse +
                     " is not a valid visibility value. See android.view.View VISIBLE, GONE, and INVISIBLE");
         }
-        this.view = view;
         this.visibilityOnFalse = visibilityOnFalse;
     }
 
     @Override
-    public void call(Boolean aBoolean) {
+    public void call(View view, Boolean aBoolean) {
         int visibility = aBoolean ? View.VISIBLE : visibilityOnFalse;
         view.setVisibility(visibility);
     }

src/test/java/rx/functions/ViewAction1Test.java

@@ -0,0 +1,75 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx.android.functions;
+
+import android.view.View;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.Robolectric;
+import org.robolectric.RobolectricTestRunner;
+
+import rx.subjects.PublishSubject;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static rx.android.TestUtil.createView;
+
+@RunWith(RobolectricTestRunner.class)
+public class ViewAction1Test {
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void callIsNotExecutedWithAReleasedReference() {
+        final View view = null; // simulate a released WeakReference
+        final PublishSubject<Boolean> subject = PublishSubject.create();
+        final ViewAction1Impl action = new ViewAction1Impl(view);
+        subject.subscribe(action);
+
+        assertFalse(action.wasCalled);
+        subject.onNext(true);
+        assertFalse(action.wasCalled);
+    }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void callIsExecutedWithARetainedReference() {
+        final View view = createView();
+        final PublishSubject<Boolean> subject = PublishSubject.create();
+        final ViewAction1Impl action = new ViewAction1Impl(view);
+        subject.subscribe(action);
+
+        assertFalse(action.wasCalled);
+        subject.onNext(true);
+        assertTrue(action.wasCalled);
+    }
+
+    private static class ViewAction1Impl extends ViewAction1<View, Boolean> {
+
+        boolean wasCalled = false;
+
+        ViewAction1Impl(View view) {
+            super(view);
+        }
+
+        @Override
+        public void call(View view, Boolean aBoolean) {
+            wasCalled = true;
+        }
+
+    }
+
+}