Adds progressViewOffset to RefreshControl

Summary:
Add the possibility to define a progress view top offset to RefreshControl on android. As i comment in #6740, contentInset does the trick on IOS.

Looking android documentation seems that exists a possible solution:
http://developer.android.com/reference/android/support/v4/widget/SwipeRefreshLayout.html#setProgressViewOffset(boolean, int, int)

This pull request implement that but keeping it simple, only a top offset.

For example, now we could put navigation bar over the scrollview (or listview) and define a progressViewOffset on RefreshView in order to start behind the navigation. At this point we could make some kind of coordinator layout to hide/show navigation on scroll.

To maintain the default behavior, start point is equal to start point minus progress circle diameter in order to create that progress circle before the start point.
Closes #6759

Differential Revision: D3240664

Pulled By: mkonicek

fb-gh-sync-id: ccf866272e871811c1c6dcc2a34f5c217967feee
fbshipit-source-id: ccf866272e871811c1c6dcc2a34f5c217967feee

Libraries/Components/RefreshControl/RefreshControl.js

@@ -122,6 +122,11 @@ const RefreshControl = React.createClass({
      * @platform android
      */
     size: React.PropTypes.oneOf(RefreshLayoutConsts.SIZE.DEFAULT, RefreshLayoutConsts.SIZE.LARGE),
+    /**
+     * Progress view top offset
+     * @platform android
+     */
+    progressViewOffset: React.PropTypes.number,
   },
 
   _nativeRef: (null: any),

Libraries/PullToRefresh/PullToRefreshViewAndroid.android.js

@@ -48,6 +48,11 @@ var PullToRefreshViewAndroid = React.createClass({
      * The background color of the refresh indicator
      */
     progressBackgroundColor: ColorPropType,
+    /**
+     * Progress view top offset
+     * @platform android
+     */
+    progressViewOffset: React.PropTypes.number,
     /**
      * Whether the view should be indicating an active refresh
      */
@@ -80,6 +85,7 @@ var PullToRefreshViewAndroid = React.createClass({
         progressBackgroundColor={this.props.progressBackgroundColor}
         ref={NATIVE_REF}
         refreshing={this.props.refreshing}
+        progressViewOffset={this.props.progressViewOffset}
         size={this.props.size}
         style={this.props.style}>
         {onlyChild(this.props.children)}

ReactAndroid/src/main/java/com/facebook/react/views/swiperefresh/SwipeRefreshLayoutManager.java

@@ -20,6 +20,7 @@
 import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.common.MapBuilder;
 import com.facebook.react.common.SystemClock;
+import com.facebook.react.uimanager.PixelUtil;
 import com.facebook.react.uimanager.ThemedReactContext;
 import com.facebook.react.uimanager.UIManagerModule;
 import com.facebook.react.uimanager.ViewGroupManager;
@@ -32,6 +33,8 @@
  */
 public class SwipeRefreshLayoutManager extends ViewGroupManager<ReactSwipeRefreshLayout> {
 
+  public static final float REFRESH_TRIGGER_DISTANCE = 48;
+
   @Override
   protected ReactSwipeRefreshLayout createViewInstance(ThemedReactContext reactContext) {
     return new ReactSwipeRefreshLayout(reactContext);
@@ -82,6 +85,21 @@ public void run() {
     });
   }
 
+  @ReactProp(name = "progressViewOffset", defaultFloat = 0)
+  public void setProgressViewOffset(final ReactSwipeRefreshLayout view, final float offset) {
+    // Use `post` to get progress circle diameter properly
+    // Otherwise returns 0
+    view.post(new Runnable() {
+      @Override
+      public void run() {
+        int diameter = view.getProgressCircleDiameter();
+        int start = Math.round(PixelUtil.toPixelFromDIP(offset)) - diameter;
+        int end = Math.round(PixelUtil.toPixelFromDIP(offset + REFRESH_TRIGGER_DISTANCE));
+        view.setProgressViewOffset(false, start, end);
+      }
+    });
+  }
+
   @Override
   protected void addEventEmitters(
       final ThemedReactContext reactContext,