This sample demonstrates the trackball behavior in chart. Trackball is used to track a data point closer to the current mouse position or touch contact point. You can show tooltip for individual point or group of points closer to mouse position using shared properties in tooltip. Hover the chart area to view trackball and its tooltip. Touch and hold to enable trackball in touch enabled devices. Injecting Module Chart component features are segregated into individual feature-wise modules. To use trackball, we need to inject TooltipService into the @NgModule.providers section. More information on the trackball can be found in this documentation section.