Renders a Chart.js bar chart for large datasets by extending ObjReportLine with the bar chart type.
BAR — set as ReportType in def_report.
def Render(self, Param1="", Param2="", Param3="") -> str:
Inherited from ObjReportLine. Reads data from self.data_list (pre-loaded by the report engine), renders a styled <canvas> element, and injects a Chart.js initialisation script. Returns an HTML string.
Uses the Chart.js library (chart.umd.min.js) and axion.rpc.js. Overrides getChartType() to return "bar", which is passed to the Chart constructor. All other rendering, RPC polling, and options handling are inherited from ObjReportLine.
SQL data shape and options are identical to ObjReportLine:
{X-value}, {Y-value-1}, {Y-value-2}, ..., {colour-1}, {colour-2}, ...