auto layout magic

Author: kligarski

ios/RNSScreenStackHeaderSubview.mm

@@ -158,8 +158,10 @@ - (void)updateProps:(react::Props::Shared const &)props oldProps:(react::Props::
 - (void)updateLayoutMetrics:(const react::LayoutMetrics &)layoutMetrics
            oldLayoutMetrics:(const react::LayoutMetrics &)oldLayoutMetrics
 {
+#if RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
   _layoutMetrics = layoutMetrics;
   [self invalidateIntrinsicContentSize];
+#endif // RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
   CGRect frame = RCTCGRectFromRect(layoutMetrics.frame);
   // CALayer will crash if we pass NaN or Inf values.
   // It's unclear how to detect this case on cross-platform manner holistically, so we have to do it on the mounting
@@ -207,34 +209,42 @@ - (void)reactSetFrame:(CGRect)frame
 - (UIBarButtonItem *)getUIBarButtonItem
 {
   if (_barButtonItem == nil) {
-    // todo: mem leak
+#if RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
     UIView *wrapperView = [UIView new];
-    [wrapperView addSubview:self];
-
     wrapperView.translatesAutoresizingMaskIntoConstraints = NO;
+
     self.translatesAutoresizingMaskIntoConstraints = NO;
+    [wrapperView addSubview:self];
 
-    [NSLayoutConstraint activateConstraints:@[
-      [self.centerXAnchor constraintEqualToAnchor:wrapperView.centerXAnchor],
-      [self.centerYAnchor constraintEqualToAnchor:wrapperView.centerYAnchor],
-      [wrapperView.widthAnchor constraintGreaterThanOrEqualToAnchor:self.widthAnchor],
-      [wrapperView.heightAnchor constraintGreaterThanOrEqualToAnchor:self.heightAnchor]
-    ]];
-    //
-    //    [self setContentCompressionResistancePriority:UILayoutPriorityRequired
-    //    forAxis:UILayoutConstraintAxisHorizontal]; [self
-    //    setContentCompressionResistancePriority:UILayoutPriorityRequired forAxis:UILayoutConstraintAxisVertical];
+    [self.centerXAnchor constraintEqualToAnchor:wrapperView.centerXAnchor].active = YES;
+    [self.centerYAnchor constraintEqualToAnchor:wrapperView.centerYAnchor].active = YES;
+
+    NSLayoutConstraint *widthEqual = [wrapperView.widthAnchor constraintEqualToAnchor:self.widthAnchor];
+    widthEqual.priority = UILayoutPriorityDefaultHigh;
+    widthEqual.active = YES;
+
+    NSLayoutConstraint *heightEqual = [wrapperView.heightAnchor constraintEqualToAnchor:self.heightAnchor];
+    heightEqual.priority = UILayoutPriorityDefaultHigh;
+    heightEqual.active = YES;
+
+    [self setContentHuggingPriority:UILayoutPriorityRequired forAxis:UILayoutConstraintAxisHorizontal];
+    [self setContentHuggingPriority:UILayoutPriorityRequired forAxis:UILayoutConstraintAxisVertical];
 
     _barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:wrapperView];
-    [self configureBarButtonItem];
+#else // RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
+    _barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:self];
+#endif // RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
   }
+
   return _barButtonItem;
 }
 
+#if RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
 - (CGSize)intrinsicContentSize
 {
   return RCTCGSizeFromSize(_layoutMetrics.frame.size);
 }
+#endif // RNS_IPHONE_OS_VERSION_AVAILABLE(26_0)
 
 - (void)configureBarButtonItem
 {