Converted zIndex to integers

Summary: Converted the zIndex property on iOS to NSInteger instead of double. This is consistent with the CSS spec, and helps to simplify the Android implementation.

Reviewed By: javache

Differential Revision: D3411491

fbshipit-source-id: 902ebc29aac39a65f7e8707a28607655f9f5052c

React/Views/RCTShadowView.h

@@ -132,7 +132,7 @@ typedef void (^RCTApplierBlock)(NSDictionary<NSNumber *, UIView *> *viewRegistry
 /**
  * z-index, used to override sibling order in the view
  */
-@property (nonatomic, assign) double zIndex;
+@property (nonatomic, assign) NSInteger zIndex;
 
 /**
  * Calculate property changes that need to be propagated to the view.

React/Views/RCTShadowView.m

@@ -610,7 +610,7 @@ RCT_STYLE_PROPERTY(FlexWrap, flexWrap, flex_wrap, css_wrap_type_t)
   [self dirtyPropagation];
 }
 
-- (void)setZIndex:(double)zIndex
+- (void)setZIndex:(NSInteger)zIndex
 {
   _zIndex = zIndex;
   if (_superview) {

React/Views/RCTView.h

@@ -46,7 +46,7 @@
  * inherited from UIView+React, but we override it here to reduce the boxing
  * and associated object overheads.
  */
-@property (nonatomic, assign) double reactZIndex;
+@property (nonatomic, assign) NSInteger reactZIndex;
 
 /**
  * This is an optimization used to improve performance

React/Views/RCTViewManager.m

@@ -246,7 +246,7 @@ RCT_VIEW_BORDER_RADIUS_PROPERTY(TopRight)
 RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomLeft)
 RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomRight)
 
-RCT_REMAP_VIEW_PROPERTY(zIndex, reactZIndex, double)
+RCT_REMAP_VIEW_PROPERTY(zIndex, reactZIndex, NSInteger)
 
 #pragma mark - ShadowView properties
 
@@ -292,6 +292,6 @@ RCT_EXPORT_SHADOW_PROPERTY(position, css_position_type_t)
 
 RCT_EXPORT_SHADOW_PROPERTY(onLayout, RCTDirectEventBlock)
 
-RCT_EXPORT_SHADOW_PROPERTY(zIndex, double)
+RCT_EXPORT_SHADOW_PROPERTY(zIndex, NSInteger)
 
 @end

React/Views/UIView+React.h

@@ -28,7 +28,7 @@
 /**
  * z-index, used to override sibling order in didUpdateReactSubviews.
  */
-@property (nonatomic, assign) double reactZIndex;
+@property (nonatomic, assign) NSInteger reactZIndex;
 
 /**
  * The reactSubviews array, sorted by zIndex. This value is cached and

React/Views/UIView+React.m

@@ -87,12 +87,12 @@
   [subview removeFromSuperview];
 }
 
-- (double)reactZIndex
+- (NSInteger)reactZIndex
 {
-  return [objc_getAssociatedObject(self, _cmd) doubleValue];
+  return [objc_getAssociatedObject(self, _cmd) integerValue];
 }
 
-- (void)setReactZIndex:(double)reactZIndex
+- (void)setReactZIndex:(NSInteger)reactZIndex
 {
   objc_setAssociatedObject(self, @selector(reactZIndex), @(reactZIndex), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }