iOS Charting Documentation - SciChart iOS Charts SDK v3.x

SCISeriesSelectionModifier

SciChart features the SCISeriesSelectionModifier, which allows selection of the upmost RenderableSeries at a touch position:

Series Selection Modifier

NOTE: Examples of the SCISeriesSelectionModifier usage can be found in the SciChart iOS Examples Suite as well as on GitHub:

SCISeriesSelectionModifier Usage

The SCISeriesSelectionModifier allows setting of SelectedSeriesStyle of ISCIStyle type, which is applied to a RenderableSeries after it has been selected by the modifier. Internally, the modifier modifies the ISCIRenderableSeriesCore.isSelected property on the topmost RenderableSeries to make it selected and tries to apply the ISCIStyle onto ISCIRenderableSeriesCore.selectedSeriesStyle property.

The SelectedSeriesStyle has to conform to the ISCIStyle protocol, which requires implementation of the following:

Method Description
-[ISCIStyle tryApplyStyleTo:] In this method you have to make the desired changes to a RenderableSeries. It is called when a series gets selected.
-[ISCIStyle tryDiscardStyleFrom:] In this method you have to discard all the changes made in the -[ISCIStyle tryApplyStyleTo:] call.
ISCIStyle.styleableObjectType Provides the type of an object (RenderableSeries) that this Style is to be applied to.

For convenience purposes, there is a base implementation provided in SCIStyleBase class. You can derive from it then you will only need to implement the -applyStyleInternalTo: and -discardStyleInternalFrom: methods instead. Please find a code sample below.

NOTE: If you need to be able to select multiple RenderableSeries of different types, you can return the ISCIRenderableSeries as the RenderableSeries type, as it is shown in the code sample below. Alternatively, it is possible to have several SCISeriesSelectionModifiers instances with ISCIStyles for different RenderableSeries types with the receiveHandledEvents = YES.

Adding a SCISeriesSelectionModifier to a Chart

Any Chart Modifier can be added to a SCIChartSurface via the ISCIChartSurface.chartModifiers property and SCISeriesSelectionModifier with no difference.

In the example below, we will create SelectedSeriesStyle and use it with SCISeriesSelectionModifier:

#import <SciChart/SCIStyleBase+Protected.h> @interface SelectedSeriesStyle : SCIStyleBase<id<ISCIRenderableSeries>> @end @implementation SelectedSeriesStyle { SCISolidPenStyle *_selectedStrokeStyle; id<ISCIPointMarker> _selectedPointMarker; } - (instancetype)init { self = [super initWithStyleableType:SCIRenderableSeriesBase.class]; if (self) { _selectedPointMarker = [SCIEllipsePointMarker new]; _selectedPointMarker.size = CGSizeMake(10, 10); _selectedPointMarker.fillStyle = [[SCISolidBrushStyle alloc] initWithColorCode:0xFFFF00DC]; _selectedPointMarker.strokeStyle = [[SCISolidPenStyle alloc] initWithColor:UIColor.whiteColor thickness:1]; _selectedStrokeStyle = [[SCISolidPenStyle alloc] initWithColor:UIColor.whiteColor thickness:4]; } return self; } - (void)applyStyleInternalTo:(id<ISCIRenderableSeries>)styleableObject { [self putProperty:Stroke value:styleableObject.strokeStyle intoObject:styleableObject]; [self putProperty:PointMarker value:styleableObject.pointMarker intoObject:styleableObject]; styleableObject.strokeStyle = _selectedStrokeStyle; styleableObject.pointMarker = _selectedPointMarker; } - (void)discardStyleInternalFrom:(id<ISCIRenderableSeries>)styleableObject { SCIPenStyle *penStyle = [self getValueFromProperty:Stroke ofType:SCISolidPenStyle.class fromObject:styleableObject]; id<ISCIPointMarker> pointMarker = [self getValueFromProperty:PointMarker ofType:SCIEllipsePointMarker.class fromObject:styleableObject]; styleableObject.strokeStyle = penStyle; styleableObject.pointMarker = pointMarker; } @end
class SelectedSeriesStyle: SCIStyleBase<ISCIRenderableSeries> { let Stroke = “Stroke” let selectedStrokeStyle = SCISolidPenStyle(color: .white, thickness: 4) let PointMarker = “PointMarker” let selectedPointMarker: ISCIPointMarker init() { selectedPointMarker = SCIEllipsePointMarker() selectedPointMarker.size = CGSize(width: 10, height: 10) selectedPointMarker.fillStyle = SCISolidBrushStyle(colorCode: 0xFFFF00DC) selectedPointMarker.strokeStyle = SCISolidPenStyle(color: .white, thickness: 1) super.init(styleableType: SCIRenderableSeriesBase.self) } override func applyStyleInternal(to styleableObject: ISCIRenderableSeries!) { putProperty(Stroke, value: styleableObject.strokeStyle, intoObject: styleableObject) putProperty(PointMarker, value: styleableObject.pointMarker, intoObject: styleableObject) styleableObject.strokeStyle = selectedStrokeStyle styleableObject.pointMarker = selectedPointMarker } override func discardStyleInternal(from styleableObject: ISCIRenderableSeries!) { let penStyle = getValueFromProperty(Stroke, ofType: SCISolidPenStyle.self, fromObject: styleableObject) let pointMarker = getValueFromProperty(PointMarker, ofType: ISCIPointMarker.self, fromObject: styleableObject) styleableObject.strokeStyle = penStyle as? SCIPenStyle styleableObject.pointMarker = pointMarker as? ISCIPointMarker } }
private class SelectedSeriesStyle : SCIStyleBase<SCIRenderableSeriesBase> { private readonly SCIPenStyle _selectedStrokeStyle = new SCISolidPenStyle(UIColor.White, 4f); private readonly SCIEllipsePointMarker _selectedPointMarker; private const string Stroke = “Stroke”; private const string PointMarker = “PointMarker”; public SelectedSeriesStyle() { _selectedPointMarker = new SCIEllipsePointMarker { Size = new CGSize(10, 10), FillStyle = new SCISolidBrushStyle(0xFFFF00DC), StrokeStyle = new SCISolidPenStyle(UIColor.White, 1f) }; } protected override void ApplyStyle(SCIRenderableSeriesBase styleableObject) { PutPropertyValue(styleableObject, Stroke, styleableObject.StrokeStyle); PutPropertyValue(styleableObject, PointMarker, styleableObject.PointMarker); styleableObject.StrokeStyle = _selectedStrokeStyle; styleableObject.PointMarker = _selectedPointMarker; } protected override void DiscardStyle(SCIRenderableSeriesBase styleableObject) { styleableObject.StrokeStyle = GetPropertyValue(styleableObject, Stroke); styleableObject.PointMarker = GetPropertyValue(styleableObject, PointMarker); } }

Now, create and add SCISeriesSelectionModifier onto your SCIChartSurface:

// Assume a surface has been created and configured somewhere id<ISCIChartSurface> surface; // Create a SCISeriesSelectionModifier SCISeriesSelectionModifier *seriesSelectionModifier = [SCISeriesSelectionModifier new]; // Set a style which will be applied to a RenderableSeries when selected seriesSelectionModifier.selectedSeriesStyle = [SelectedSeriesStyle new]; // Add the modifier to the surface [self.surface.chartModifiers add:seriesSelectionModifier];
// Assume a surface has been created and configured somewhere let surface: ISCIChartSurface // Create a SCISeriesSelectionModifier let seriesSelectionModifier = SCISeriesSelectionModifier() // Set a style which will be applied to a RenderableSeries when selected seriesSelectionModifier.selectedSeriesStyle = SelectedSeriesStyle() // Add the modifier to the surface self.surface.chartModifiers.add(seriesSelectionModifier)
// Assume a surface has been created and configured somewhere IISCIChartSurface surface; // Create a SCISeriesSelectionModifier with a style which will be applied to a RenderableSeries when selected var seriesSelectionModifier = new SCISeriesSelectionModifier { SelectedSeriesStyle = new SelectedSeriesStyle() }; // Add the modifier to the surface Surface.ChartModifiers.Add(seriesSelectionModifier);

NOTE: To learn more about features available, Chart Modifier APIs article.