fix(ios): may render squashed at non-default aspect ratios

Author: alpha0010

cpp/PdfViewShadowNode.cpp

@@ -17,26 +17,25 @@ ShadowNodeTraits PdfViewShadowNode::BaseTraits()
 Size PdfViewShadowNode::measureContent(
   const LayoutContext& layoutContext,
   const LayoutConstraints& layoutConstraints) const {
-  int pageWidth = getStateData().getPageWidth();
-  int pageHeight = getStateData().getPageHeight();
-  Float aspectRatio = static_cast<Float>(pageWidth) / pageHeight;
-  Float targetWidth = layoutConstraints.maximumSize.height * aspectRatio;
-  if (std::isinf(layoutConstraints.maximumSize.width) || layoutConstraints.maximumSize.width < 1) {
-    if (std::isinf(layoutConstraints.maximumSize.height) || layoutConstraints.maximumSize.height < 1) {
-      // No restrictions on dimensions? Use pdf dimensions.
-      return {static_cast<Float>(pageWidth), static_cast<Float>(pageHeight)};
-    }
-    // No width requirements? Scale page to match requested height.
-    return {targetWidth, layoutConstraints.maximumSize.height};
+  Float pageWidth = getStateData().getPageWidth();
+  Float pageHeight = getStateData().getPageHeight();
+  Float aspectRatio = pageWidth / pageHeight;
+  if (std::isfinite(layoutConstraints.maximumSize.width)) {
+    // Scale page to match requested width.
+    pageWidth = layoutConstraints.maximumSize.width;
+    pageHeight = pageWidth / aspectRatio;
   }
-
-  if (targetWidth <= layoutConstraints.maximumSize.width) {
-    // When scaled to match requested height, page scaled width is
-    // within width bounds. Scale page to match requested height.
-    return {targetWidth, layoutConstraints.maximumSize.height};
+  if (std::isfinite(layoutConstraints.maximumSize.height)) {
+    // Scale page to match requested height.
+    pageHeight = std::isfinite(layoutConstraints.maximumSize.width)
+      ? std::min(pageHeight, layoutConstraints.maximumSize.height)
+      : layoutConstraints.maximumSize.height;
+    pageWidth = pageHeight * aspectRatio;
   }
-  // Scale page to match requested width.
-  return {layoutConstraints.maximumSize.width, layoutConstraints.maximumSize.width / aspectRatio};
+  return {
+    std::max(pageWidth, layoutConstraints.minimumSize.width),
+    std::max(pageHeight, layoutConstraints.minimumSize.height)
+  };
 }
 
 } // namespace facebook::react

ios/PdfView.mm

@@ -65,6 +65,12 @@ - (instancetype)initWithFrame:(CGRect)frame
     return self;
 }
 
+- (void)prepareForRecycle
+{
+    [super prepareForRecycle];
+    [_view prepareForRecycle];
+}
+
 - (void)updateProps:(Props::Shared const &)props oldProps:(Props::Shared const &)oldProps
 {
     const auto &newViewProps = *std::static_pointer_cast<PdfViewProps const>(props);

ios/PdfView.swift

@@ -66,6 +66,12 @@ public class PdfView: UIView {
         }
     }
 
+    @objc public func prepareForRecycle() {
+        source = ""
+        resizeMode = ResizeMode.CONTAIN
+        previousBounds = .zero
+    }
+
     @objc public func updateProps(annot: String, annotStr: String, pg: Int, rsMd: ResizeMode, src: String) {
         var isDirty = false
         var needsMeasure = false