onPinchStart method Null safety

void onPinchStart(
  1. ChartAxis axis,
  2. double firstX,
  3. double firstY,
  4. double secondX,
  5. double secondY,
  6. double scaleFactor
)

Chart can be pinched to zoom in / zoom out for starting position.

  • firstX - first position of pinching in X axis.
  • firstY - first position of pinching in Y axis.
  • secondX - last position of pinching in X axis.
  • secondY - last position of pinching in X axis. scaleFacator - scale factor is a number which scales some quantity in charts.

Implementation

void onPinchStart(ChartAxis axis, double firstX, double firstY,
    double secondX, double secondY, double scaleFactor);