feat(macos): support selectionColor via NSTextView.selectedTextAttributes (#265)

Author: hryhoriiK97

apps/macos-example/src/App.tsx

@@ -83,6 +83,7 @@ export default function App() {
               onLinkPress={handleLinkPress}
               markdownStyle={markdownStyle}
               contextMenuItems={contextMenuItems}
+              selectionColor="#DCDDFE"
             />
           </ScrollView>
           {lastLink != null && (

ios/utils/ENRMUIKit.h

@@ -203,12 +203,16 @@ static inline void ENRMSetCursorColor(ENRMPlatformTextView *textView, RCTUIColor
 #endif
 }
 
-/// Cross-platform selection color: iOS uses tintColor (affects both cursor and selection);
-/// macOS selection highlight is managed by the system and not directly settable.
+/// Cross-platform selection color: iOS uses tintColor (also affects the caret
+/// and selection handles); macOS sets the selection background via
+/// `selectedTextAttributes`. Pass `nil` to restore the system default.
 static inline void ENRMSetSelectionColor(ENRMPlatformTextView *textView, RCTUIColor *color)
 {
 #if !TARGET_OS_OSX
   textView.tintColor = color;
+#else
+  RCTUIColor *resolved = color ?: [NSColor selectedTextBackgroundColor];
+  textView.selectedTextAttributes = @{NSBackgroundColorAttributeName : resolved};
 #endif
 }
 

src/EnrichedMarkdownNativeComponent.ts

@@ -277,9 +277,10 @@ export interface NativeProps extends ViewProps {
    * Color of the text selection highlight.
    *
    * On iOS, this also affects the caret and selection handle colors
-   * (they share a single tint).
+   * (they share a single tint). On macOS, only the selection background
+   * is affected.
    *
-   * @platform ios, android, web
+   * @platform ios, android, macos, web
    */
   selectionColor?: ColorValue;
   /**

src/EnrichedMarkdownTextNativeComponent.ts

@@ -277,9 +277,10 @@ export interface NativeProps extends ViewProps {
    * Color of the text selection highlight.
    *
    * On iOS, this also affects the caret and selection handle colors
-   * (they share a single tint).
+   * (they share a single tint). On macOS, only the selection background
+   * is affected.
    *
-   * @platform ios, android, web
+   * @platform ios, android, macos, web
    */
   selectionColor?: ColorValue;
   /**

src/types/MarkdownTextProps.ts

@@ -95,9 +95,10 @@ export interface EnrichedMarkdownTextProps extends Omit<ViewProps, 'style'> {
    * Color of the text selection highlight.
    *
    * On iOS, this also affects the caret and selection handle colors
-   * (they share a single tint).
+   * (they share a single tint). On macOS, only the selection background
+   * is affected.
    *
-   * @platform ios, android, web
+   * @platform ios, android, macos, web
    */
   selectionColor?: ColorValue;
   /**