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

SCICursorModifier

SciChart features a Cursor or Crosshair modifier provided by the SCICursorModifier. It allows to display a crosshair at the touch-point and X-Axis and/or Y-Axis labels. The SCICursorModifier is also able to display an aggregated tooltip (all series in one tooltip).

Cursor Modifier

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

Obj-C/Swift Example

Xamarin Example

SCICursorModifier Usage

The SCICursorModifier allows inspecting RenderableSeries at a touch point. For convenience, the actual hit-test point is located a bit upper. Tooltips will appear to the side of it, showing the hit-test result for all RenderableSeries above the cursor horizontal line. Also, the SCICursorModifier shows labels on axes for its horizontal, vertical lines.

Cursor Modifier Usage

For hit-testing series parts that are close to the chart boundaries, a multi-touch finger drag can be used:

Cursor Modifier Usage Near Edge

SCICursorModifier Features

Besides the SCICursorModifier specific features, there are some common features which are shared between SCITooltipModifier, SCIRolloverModifier and SCICursorModifier via common SCITooltipModifierBase class.

Common Features

Feature	Description
`SCITooltipModifierBase.showTooltip`	Allows to hide or show modifier’s Tooltips.
`SCITooltipModifierBase.useInterpolation`	Allows to show interpolated values between data points. It is a `YES` by default. If `NO` - modifier’s Tooltips will report the info about closest data points.
`SCITooltipModifierBase.sourceMode`	Allows to specify which `ISCIRenderableSeries` are to be inspected by a modifier, e.g. Visible, Selected, etc. Other will be ignored by the modifier. Expects a member of the `SCISourceMode` enumeration.

Specific Features

Feature	Description
`SCICursorModifier.offset`	Specifies how far the hit-test point is from the actual touch point. This value will be used for either `X` or `Y` coordinate, or both, depending on `markerPlacement`.
`SCICursorModifier.customPointOffset`	Specifies how far the hit-test point is from the actual touch point. As opposed to `offset`, both `X` and `Y` coordinate will always be applied.
`SCICursorModifier.markerPlacement`	Allows to specify the position of the hit-test point relative to the touch point, e.g. Left, Top, etc… Expects a member of the `SCIPlacement` enumeration.
`SCICursorModifier.tooltipPosition`	Allows to specify the position of modifier’s Tooltips relative to the hit-test point, e.g. TopLeft, BottomRight, etc…. Expects a member of the `SCITooltipPosition` enumeration.
`SCICursorModifier.crosshairPenStyle`	Allows to specify `SCIPenStyle` which will be used to draw cursor crosshair lines.
`SCICursorModifier.displayTooltipOverAxis`	Allows to display the tooltip when drag over the Axis area.

Adding a SCICursorModifier to a Chart

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

    // Assume a surface has been created and configured somewhere
    id<ISCIChartSurface> surface;

    // Create a Modifier and add modifier to the surface
    [self.surface.chartModifiers add:[SCICursorModifier new]];

    // Assume a surface has been created and configured somewhere
    let surface: ISCIChartSurface

    // Create a Modifier and add modifier to the surface
    self.surface.chartModifiers.add(SCICursorModifier())

    // Assume a surface has been created and configured somewhere
    IISCIChartSurface surface;

    // Create a Modifier and add modifier to the surface
    Surface.ChartModifiers.Add(new SCICursorModifier());

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