iOS & macOS Charting Documentation - SciChart iOS & macOS Charts SDK v4.x

SCIFibonacciRetracementCreationModifier

The SCIFibonacciRetracementCreationModifier is a custom gesture modifier used for interactive creation of Fibonacci Retracement annotations on a SciChart surface.

It enables users to place two key points (Start → End) using touch gestures, with real-time visual feedback during placement. Style properties set on the modifier (stroke, levels, regionColors, fillOpacity, connector line, and label options) are applied to each annotation as it is created.

Overview

The modifier handles the full lifecycle of Fibonacci Retracement annotation creation:

Sequential point placement via touch interaction
Real-time dragging feedback for each point
Automatic completion after the final point (End)
Immediate reset for continuous drawing

Once completed, the annotation remains on the chart and a callback is triggered.

Interaction Behavior

The creation flow follows a structured sequence:

Per Point Interaction (Start → End)

Gesture	Behavior
Touch Down	Places the current point at the touch location
Drag	Moves the point dynamically in real-time
Touch Up	Locks the point and advances to the next one

Completion

After placing the End point, the annotation is finalized
The SCIAnnotationCreationModifierBase.annotationCreationCompletionListener callback is invoked
The modifier resets immediately, ready for a new annotation

Fibonacci Retracement Annotation

Retrieving Annotation Points After Drawing Completion

After an annotation drawing is completed, you can retrieve its underlying points using: -[ISCITradingAnnotation getBaseDataValues] -[ISCITradingAnnotation getBasePoints] Both methods return the annotation’s defining points, but in different coordinate spaces.

-[ISCITradingAnnotation getBaseDataValues]

X and Y values correspond to the chart’s actual data coordinates
Independent of pixel resolution or screen scaling
Useful for storing, analysis, or reloading annotations

-[ISCITradingAnnotation getBasePoints]

X and Y values correspond to screen pixels
Useful for rendering overlays or UI alignment

Usage Example

// Create a new Fibonacci Retracement creation modifier instance
SCIFibonacciRetracementCreationModifier *modifier = [SCIFibonacciRetracementCreationModifier new];

// Set the stroke style for the level lines
modifier.stroke = [[SCISolidPenStyle alloc] initWithColorCode:0xFFFFFFFF thickness:2];

// Configure levels and region colours
modifier.levels = @[@0, @0.236, @0.382, @0.5, @0.618, @0.786, @1];
modifier.regionColors = @[
    [SCIColor fromARGBColorCode:0xFF0EA5E9],
    [SCIColor fromARGBColorCode:0xFF22C55E],
    [SCIColor fromARGBColorCode:0xFFFACC15],
    [SCIColor fromARGBColorCode:0xFFF97316],
    [SCIColor fromARGBColorCode:0xFFEF4444],
    [SCIColor fromARGBColorCode:0xFFA855F7]
];
modifier.fillOpacity = 0.2;
modifier.showConnectorLine = YES;
modifier.fibonacciLabelPlacement = SCIFibonacciLabelPlacement_Top;

// Callback triggered when the user completes placing both points (Start, End)
// Provides access to the fully created annotation object
__weak typeof(self) weakSelf = self;
modifier.annotationCreationCompletionListener = ^(id _Nonnull createdAnnotation, SCIAnnotationCreationType type) {
    __strong typeof(weakSelf) strongSelf = weakSelf;
    if (!strongSelf) return;

    NSLog(@“Fibonacci Retracement annotation created: %@ type %@”, createdAnnotation, SCIAnnotationTypeName(type));

    if (![createdAnnotation isKindOfClass:[SCIFibonacciRetracementAnnotation class]]) return;

    SCIFibonacciRetracementAnnotation *fib = (SCIFibonacciRetracementAnnotation *)createdAnnotation;
    NSArray *points = [fib getBaseDataValues];

    // Get data points
    // Index mapping: 0 = Start, 1 = End
    NSLog(@“[Fibonacci] Start: date=%@  price=%@”, points[0].x, points[0].y);
    NSLog(@“[Fibonacci] End: date=%@  price=%@”, points[1].x, points[1].y);
};

// Add the modifier to the chart surface
[self.surface.chartModifiers add:modifier];

// Create a new Fibonacci Retracement creation modifier instance
self.fibonacciModifier = SCIFibonacciRetracementCreationModifier()

// Set the stroke style for the level lines
self.fibonacciModifier.stroke = SCISolidPenStyle(color: 0xFFFFFFFF, thickness: 2)

// Configure levels and region colours
self.fibonacciModifier.levels = [0, 0.236, 0.382, 0.5, 0.618, 0.786, 1].map { NSNumber(value: $0) }
self.fibonacciModifier.regionColors = [0xFF0EA5E9, 0xFF22C55E, 0xFFFACC15,
                           0xFFF97316, 0xFFEF4444, 0xFFA855F7].map { SCIColor.fromARGBColorCode($0) }
self.fibonacciModifier.fillOpacity = 0.2
self.fibonacciModifier.showConnectorLine = true
self.fibonacciModifier.fibonacciLabelPlacement = .top
self.fibonacciModifier.isEditable = true

// Callback triggered when the user completes placing both points (Start, End)
// Provides access to the fully created annotation object
self.fibonacciModifier.annotationCreationCompletionListener = { [weak self] createdAnnotation, type in
    guard self != nil else { return }

    print(“Fibonacci Retracement annotation created: \(createdAnnotation), type: \(SCIAnnotationTypeName(type))”)

    guard let fib = createdAnnotation as? SCIFibonacciRetracementAnnotation else { return }
    let arrPoints = fib.getBaseDataValues()

    // Get data points
    // Index mapping: 0 = Start, 1 = End
    print(“Fibonacci point Start: \(arrPoints[0].x), \(arrPoints[0].y)”)
    print(“Fibonacci point End: \(arrPoints[1].x), \(arrPoints[1].y)”)
}

// Add the modifier to the chart surface
self.surface.chartModifiers.add(items: self.fibonacciModifier)

The SCIFibonacciRetracementCreationModifier can be configured using the properties listed in the table below:

Field	Description
`SCIFibonacciRetracementCreationModifier.stroke`	Defines the `SCIPenStyle` used to draw the level lines. Supplies thickness and dash pattern; the colour of each level comes from `regionColors`.
`SCIFibonacciRetracementCreationModifier.levels`	Defines the Fibonacci ratios at which levels are drawn.
`SCIFibonacciRetracementCreationModifier.regionColors`	Defines the colours used to fill the regions between levels, treated as a ramp.
`SCIFibonacciRetracementCreationModifier.fillOpacity`	Defines the opacity applied to the filled regions, in the range 0.0 - 1.0.
`SCIFibonacciRetracementCreationModifier.showConnectorLine`	Determines whether a connector line is drawn between the two base points.
`SCIFibonacciRetracementCreationModifier.connectorLineStroke`	Defines the `SCIPenStyle` used to draw the connector line between the two base points.
`SCIFibonacciRetracementCreationModifier.fibonacciLabelPlacement`	Determines where the level labels are placed relative to their level line: `Left`, `Top`, or `Inside`.
`SCIFibonacciRetracementCreationModifier.fibonacciLabelColorMode`	Determines how the level labels are coloured: `MultiColor` (matches each level line) or `SingleColor` (uses `labelStyle`‘s text colour).
`SCIFibonacciRetracementCreationModifier.labelStyle`	Defines the `SCIFontStyle` used by the level labels.

NOTE: The xAxisId and yAxisId must be supplied if you have axis with non-default Axis Ids, e.g. in multi-axis scenario.

Best Practices

Disable conflicting gesture modifiers during drawing for better UX
Use the CompletionListener to validate or store annotations
Keep levels and regionColors in sync so each region gets an intended colour
Customize stroke, fillOpacity, and regionColors for better visual distinction
Call reset when switching tools or exiting drawing mode

Notes

The modifier automatically resets after completing the End point
Only one annotation is created per interaction cycle
Designed for trend-based Fibonacci retracement analysis on financial charts