Renders an Apache ECharts heatmap chart with a visual map colour scale.
ECHARTSHEATMAP — set as ReportType in def_report.
def Render(self, Param1="", Param2="", Param3="") -> str:
Inherited from ObjReportEchartsbase. Param1, Param2, and Param3 are forwarded in the RPC payload for SQL token substitution. Returns an HTML string containing a styled panel and an ECharts initialisation script.
Uses the Apache ECharts JS library. The SQL query must return rows with three columns: x-axis category, y-axis category, and numeric value. Unique x and y values are collected from the data to build the axis categories; a visualMap component is added automatically with the range scaled to the data maximum. Option building is handled by ObjReportEchartsbase._build_heatmap_option.