toOptionsJSON method
Implementation
@override
void toOptionsJSON(StringBuffer buffer) {
super.toOptionsJSON(buffer);
if (zoomIn != null) {
buffer.writeAll(['"zoomIn":', zoomIn?.toJSON(), ','], '');
}
if (zoomOut != null) {
buffer.writeAll(['"zoomOut":', zoomOut?.toJSON(), ','], '');
}
}