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

The SCIZoomExtentsModifier

SciChart iOS provides the ability to zoom-to-fit the entire chart double-tapping it via the SCIZoomExtentsModifier, available out of the box.

Besides common features which are inherited from the SCIChartModifierBase class, the SCIZoomExtentsModifier allows to control its specific features via the following properties:

SCIZoomExtentsModifier.direction - allows to restrict zooming to the horizontal or vertical direction only if needed.
SCIZoomExtentsModifier.isAnimated - allows to switch on/off the animation on zoom out.
SCIZoomExtentsModifier.executeOn - allows to specify the trigger action for the modifier via the SCIExecuteOn enumeration.

NOTE: There are several modes defined by the SCIExecuteOn enumeration, such as Single Tap, Double Tap, Long Press, and Fling.

Adding a SCIZoomExtentsModifier to a Chart

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

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

    // Create a Modifier
    SCIZoomExtentsModifier *zoomExtentsModifier = [SCIZoomExtentsModifier new];
    zoomExtentsModifier.direction = SCIDirection2D_XDirection;
    zoomExtentsModifier.executeOn = SCIExecuteOn_DoubleTap;
    zoomExtentsModifier.isAnimated = YES;

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

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

    // Create a Modifier
    let zoomExtentsModifier = SCIZoomExtentsModifier()
    zoomExtentsModifier.direction = .xDirection
    zoomExtentsModifier.executeOn = .doubleTap
    zoomExtentsModifier.isAnimated = true

    // Add the modifier to the surface
    self.surface.chartModifiers.add(zoomExtentsModifier)

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

    // Create a Modifier
    var zoomExtentsModifier = new SCIZoomExtentsModifier();
    zoomExtentsModifier.Direction = SCIDirection2D.XDirection;
    zoomExtentsModifier.ExecuteOn = SCIExecuteOn.DoubleTap;
    zoomExtentsModifier.IsAnimated = true;

    // Add the modifier to the surface
    Surface.ChartModifiers.Add(zoomExtentsModifier);

Additional Properties

Restricting Interaction to a Single Direction (X or Y)

Interaction for this modifier can be limited to a specific axis direction by configuring the direction property. Set direction to one of the SCIDirection2D values to restrict the modifier to the X-axis, Y-axis, or both.

zoomExtentsModifier.direction = SCIDirection2D_XyDirection; // Allows interaction in both directions
zoomExtentsModifier.direction = SCIDirection2D_XDirection;  // X-axis only
zoomExtentsModifier.direction = SCIDirection2D_YDirection;  // Y-axis only

zoomExtentsModifier.direction = .xyDirection    // Allows interaction in both directions
zoomExtentsModifier.direction = .xDirection     // X-axis only
zoomExtentsModifier.direction = .yDirection     // Y-axis only

Include/Exclude Certain Axis from Zoom Extent

The SCIZoomExtentsModifier allows you to include or exclude certain axis from the zoom entent operation. This feature is especially useful in charts with multiple axes, where you may want to zoom only selected axes while keeping others unchanged. By default all axis are included, to exclude one or more X or Y axis, set the following property:

// Exclude a specific axis from the pan zoom operation
[zoomExtentsModifier includeXAxis:xAxis isIncluded:NO];
[zoomExtentsModifier includeYAxis:yAxis isIncluded:NO];

// Include a specific axis from the pan zoom operation
[zoomExtentsModifier includeXAxis:xAxis isIncluded:YES];
[zoomExtentsModifier includeYAxis:yAxis isIncluded:YES];

// Reset flags
[zoomExtentsModifier includeAll];
[zoomExtentsModifier excludeAll];

// Exclude a specific axis from the pan zoom operation
zoomExtentsModifier.includeXAxis(xAxis, isIncluded: false)
zoomExtentsModifier.includeYAxis(yAxis, isIncluded: false)

// Include a specific axis from the pan zoom operation
zoomExtentsModifier.includeXAxis(xAxis, isIncluded: true)
zoomExtentsModifier.includeYAxis(yAxis, isIncluded: true)

// Reset flags
zoomExtentsModifier.includeAll()
zoomExtentsModifier.excludeAll()

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

Programmatically Zoom to Extents

You can also run Zoom to Extents functionality programmatically without adding SCIZoomExtentsModifier. SCIChartSurface supports the following methods which you can call whenever you need to zoom the chart to fit: