preprocessProps function

Map<String, dynamic> preprocessProps(Map<String, dynamic> props)

Implementation

Map<String, dynamic> preprocessProps(Map<String, dynamic> props) {
    final processedProps = <String, dynamic>{};

    props.forEach((key, value) {
      if (value is Function) {
        // Handle event handlers - DO NOT send functions to native, only registration flags
        if (key.startsWith('on')) {
          // DON'T include the function itself - just add handler flag for native bridge detection
          processedProps['_has${key.substring(2)}Handler'] = true;
          // Store event type for registration
          processedProps['_eventType_$key'] = key;
        }
        // Skip all Function objects - they cannot be serialized over method channel
      } else if (value is Color) {
        // Convert Color objects to hex strings with alpha
        processedProps[key] =
            '#${value.value.toRadixString(16).padLeft(8, '0')}';
      } else if (value == double.infinity) {
        // Convert infinity to 100% string for percentage sizing
        processedProps[key] = '100%';
      } else if (value is String &&
          (value.endsWith('%') || value.startsWith('#'))) {
        // Pass percentage strings and color strings through directly
        processedProps[key] = value;
      } else if (key == 'width' ||
          key == 'height' ||
          key.startsWith('margin') ||
          key.startsWith('padding')) {
        // Make sure numeric values go through as doubles for consistent handling
        if (value is num) {
          processedProps[key] = value.toDouble();
        } else {
          processedProps[key] = value;
        }
      } else if (value != null) {
        processedProps[key] = value;
      }
    });

    return processedProps;
  }