StackDetails

A detailed panel component that displays comprehensive information about a selected frame, including its complete stack trace and direct child frames.

Purpose

The StackDetails component provides an in-depth view of frame relationships within the call stack. It shows the complete path from root to the selected frame and lists all direct children, making it ideal for detailed performance analysis.

Props

Prop	Type	Default	Description
selectedFrame	any | null	required	The currently selected frame data
stackTrace	any[]	[]	Array of frames from root to selected frame
children	any[]	[]	Array of direct child frames
backgroundColor	string	'#1e1e1e'	Background color of the panel
textColor	string	'#ffffff'	Text color for content
primaryColor	string	'#ff4444'	Primary theme color
secondaryColor	string	'#ffcc66'	Secondary theme color
fontFamily	string	System font stack	Font family for text
width	number | string	'100%'	Width of the panel
height	number | string	'auto'	Height of the panel
allFrames	any[]	[]	All frames for accurate color calculation

Usage Examples

Basic Usage

import { StackDetails } from './StackDetails'

function ProfilePanel({ selectedFrame, stackTrace, children }) {
  return (
    <StackDetails
      selectedFrame={selectedFrame}
      stackTrace={stackTrace}
      children={children}
    />
  )
}

With Custom Styling

<StackDetails
  selectedFrame={selectedFrame}
  stackTrace={stackTrace}
  children={children}
  backgroundColor="#0f172a"
  textColor="#f1f5f9"
  primaryColor="#3b82f6"
  secondaryColor="#10b981"
  width="400px"
  height="600px"
/>

As Overlay Panel

function FlameGraphWithDetails({ profile, selectedFrame }) {
  return (
    <div style={{ position: 'relative' }}>
      <FlameGraph profile={profile} />
      
      {selectedFrame && (
        <div style={{
          position: 'absolute',
          top: 0,
          right: 0,
          width: '400px',
          height: '100%',
          backgroundColor: '#1e1e1eF0',
          boxShadow: '-4px 0 12px rgba(0, 0, 0, 0.3)'
        }}>
          <StackDetails
            selectedFrame={selectedFrame}
            stackTrace={stackTrace}
            children={children}
            width="100%"
            height="100%"
          />
        </div>
      )}
    </div>
  )
}

Panel Structure

Header Section

• Title: "Stack Details" heading
• Selected Frame: Color-coded frame name matching flame graph colors
• Dynamic Coloring: Frame color calculated using same algorithm as flame graph

Stack Trace Section

• Title: "Stack Trace (Root → Selected)"
• Frame List: Complete path from root to selected frame
• Highlighted Selection: Selected frame shown in primary color
• Frame Details: Each frame shows:
  • Function name
  • File name and line number (if available)
  • Value (sample count)
  • Width percentage

Children Section

• Title: "Child Frames" with count
• Sorted List: Children ordered by value (descending)
• Leaf Detection: Shows "No child frames (leaf node)" for leaf frames
• Child Details: Each child shows:
  • Function name (bold)
  • File location
  • Value and width metrics

Empty State

When no frame is selected, displays:

• Centered message: "Click on a frame in the flamegraph to view stack details"
• Maintains consistent styling and dimensions
• Uses semi-transparent text for subtle appearance

Color Integration

The component integrates with flame graph colors:

• Dynamic Frame Color: Uses getFrameColorHexBySameDepthRatio() function
• Depth-Based Calculation: Colors match flame graph frame colors exactly
• Real-Time Updates: Colors update when frame selection changes
• Fallback Colors: Uses primary color when calculation unavailable

Data Handling

Robust Data Processing

• Type Safety: Handles various data types and formats
• JSON Fallback: Displays JSON for complex object values
• Safe Navigation: Null-safe access to all properties
• Flexible Input: Works with different frame data structures

Frame Information Display

For each frame, shows:

• Name: Function or method name (with JSON fallback)
• Location: File path and line number
• Metrics: Value (formatted with locale) and percentage width
• Hierarchy: Visual indication of stack relationships

Visual Features

Layout

• Scrollable Content: Auto-overflow for long lists
• Sectioned Design: Clear separation between stack trace and children
• Consistent Spacing: Proper margins and padding throughout
• Responsive Text: Scales with container size

Styling Elements

• Card Design: Subtle background and border for content sections
• Hover Effects: Interactive elements with transitions
• Typography Hierarchy: Different sizes and weights for information levels
• Color Coding: Strategic use of colors for emphasis and organization

Performance Optimizations

• Color Memoization: Expensive color calculations are cached
• Effect Optimization: Uses React.useEffect for color updates only when necessary
• Efficient Sorting: Children sorted once using useMemo
• State Management: Minimal re-renders through careful state updates

Accessibility Features

• Semantic HTML: Proper heading structure and landmarks
• CSS Classes: Descriptive class names for testing and styling
• Screen Reader Support: Meaningful text content and structure
• Keyboard Navigation: Standard scrolling and interaction patterns

Integration Points

With FullFlameGraph

• Typically used as an overlay panel
• Receives processed stack trace and children data
• Coordinates with flame graph selection state

Data Dependencies

• Stack Trace: Expects ordered array from root to selected
• Children: Expects direct child frames with value property
• All Frames: Optional but recommended for accurate coloring

Technical Implementation

• React Hooks: Uses useState and useEffect for color management
• Type Flexibility: Handles various data formats gracefully
• Error Boundaries: Graceful handling of malformed data
• Style Isolation: Self-contained styling without external dependencies

Related Components

• FullFlameGraph: Primary container that uses this component
• FlameGraph: Provides frame selection that drives this display
• FrameDetails: Complementary compact frame information
• HottestFramesBar and HottestFramesControls: Alternative navigation methods