[ios] fire onLayout

ios/Elements/RNSVGGroup.m

@@ -33,6 +33,8 @@
 - (void)renderGroupTo:(CGContextRef)context rect:(CGRect)rect
 {
     [self pushGlyphContext];
+    
+    __block CGRect groupRect = CGRectNull;
 
     [self traverseSubviews:^(UIView *node) {
         if ([node isKindOfClass:[RNSVGNode class]]) {
@@ -46,6 +48,11 @@
             }
 
             [svgNode renderTo:context rect:rect];
+            
+            CGRect nodeRect = svgNode.clientRect;
+            if (!CGRectIsEmpty(nodeRect)) {
+                groupRect = CGRectUnion(groupRect, nodeRect);
+            }
 
             if ([node isKindOfClass:[RNSVGRenderable class]]) {
                 [(RNSVGRenderable*)node resetProperties];
@@ -62,6 +69,7 @@
         return YES;
     }];
     [self setHitArea:[self getPath:context]];
+    self.clientRect = groupRect;
     [self popGlyphContext];
 }
 

ios/Elements/RNSVGSvgView.h

@@ -25,6 +25,9 @@
 @property (nonatomic, assign) RNSVGVBMOS meetOrSlice;
 @property (nonatomic, assign) BOOL responsible;
 @property (nonatomic, assign) CGRect boundingBox;
+@property (nonatomic, assign) CGAffineTransform initialCTM;
+@property (nonatomic, assign) CGAffineTransform invInitialCTM;
+
 
 
 /**

ios/Elements/RNSVGSvgView.m

@@ -135,6 +135,8 @@
 
 - (void)drawToContext:(CGContextRef)context withRect:(CGRect)rect {
 
+    self.initialCTM = CGContextGetCTM(context);
+    self.invInitialCTM = CGAffineTransformInvert(self.initialCTM);
     if (self.align) {
         _viewBoxTransform = [RNSVGViewBox getTransform:CGRectMake(self.minX, self.minY, self.vbWidth, self.vbHeight)
                                                  eRect:rect
@@ -147,7 +149,8 @@
     for (UIView *node in self.subviews) {
         if ([node isKindOfClass:[RNSVGNode class]]) {
             RNSVGNode *svg = (RNSVGNode *)node;
-            [svg renderTo:context rect:rect];
+            [svg renderTo:context
+                     rect:rect];
         } else {
             [node drawRect:rect];
         }

ios/Elements/RNSVGUse.m

@@ -49,6 +49,7 @@
         // TODO: calling yellow box here
         RCTLogWarn(@"`Use` element expected a pre-defined svg template as `href` prop, template named: %@ is not defined.", self.href);
     }
+    self.clientRect = template.clientRect;
 }
 
 - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {

ios/RNSVGNode.h

@@ -35,6 +35,9 @@ extern CGFloat const RNSVG_DEFAULT_FONT_SIZE;
 @property (nonatomic, assign) CGAffineTransform invmatrix;
 @property (nonatomic, assign) BOOL active;
 @property (nonatomic, assign) CGPathRef path;
+@property (nonatomic, assign) CGRect clientRect;
+@property (nonatomic, copy) RCTDirectEventBlock onLayout;
+
 
 /**
  * RNSVGSvgView which ownes current RNSVGNode

ios/RNSVGNode.m

@@ -145,6 +145,24 @@ CGFloat const RNSVG_DEFAULT_FONT_SIZE = 12;
     [container invalidate];
 }
 
+- (void)setClientRect:(CGRect)clientRect {
+    if (CGRectEqualToRect(_clientRect, clientRect)) {
+        return;
+    }
+    _clientRect = clientRect;
+    if (self.onLayout) {
+        self.onLayout(@{
+                        @"layout": @{
+                                @"x": @(_clientRect.origin.x),
+                                @"y": @(_clientRect.origin.y),
+                                @"width": @(_clientRect.size.width),
+                                @"height": @(_clientRect.size.height),
+                                }
+                        });
+
+    }
+}
+
 - (void)setClipPath:(NSString *)clipPath
 {
     if (_clipPath == clipPath) {

ios/RNSVGRenderable.m

@@ -187,6 +187,10 @@
         self.path = CGPathRetain(CFAutorelease(CGPathCreateCopy([self getPath:context])));
         [self setHitArea:self.path];
     }
+    
+    const CGRect pathBounding = CGPathGetBoundingBox(self.path);
+    const CGAffineTransform svgToClientTransform = CGAffineTransformConcat(CGContextGetCTM(context), self.svgView.invInitialCTM);
+    self.clientRect = CGRectApplyAffineTransform(pathBounding, svgToClientTransform);
 
     CGPathDrawingMode mode = kCGPathStroke;
     BOOL fillColor = NO;

ios/ViewManagers/RNSVGNodeManager.m

@@ -35,5 +35,7 @@ RCT_EXPORT_VIEW_PROPERTY(matrix, CGAffineTransform)
 RCT_EXPORT_VIEW_PROPERTY(clipPath, NSString)
 RCT_EXPORT_VIEW_PROPERTY(clipRule, RNSVGCGFCRule)
 RCT_EXPORT_VIEW_PROPERTY(responsible, BOOL)
+RCT_EXPORT_VIEW_PROPERTY(onLayout, RCTDirectEventBlock)
+
 
 @end

lib/extract/extractProps.js

@@ -10,7 +10,8 @@ export default function(props, ref) {
 
     const extractedProps = {
         opacity: extractOpacity(props.opacity),
-        propList: styleProperties
+        propList: styleProperties,
+        onLayout: props.onLayout
     };
 
     if (props.id) {

lib/props.js

@@ -18,6 +18,10 @@ const touchableProps = {
     delayLongPress: PropTypes.number
 };
 
+const layoutProps = {
+    onLayout: PropTypes.func
+};
+
 const responderProps = [
     ...Object.keys(PanResponder.create({}).panHandlers),
     "pointerEvents"
@@ -79,6 +83,7 @@ const pathProps = {
     ...transformProps,
     ...responderProps,
     ...touchableProps,
+    ...layoutProps,
     ...definationProps
 };