I have a problem that I have been struggling with for a few days now and would like your advice.
I wanted to create a chart with X and Y axis labels in the dashboard. After ruling out the possibility of using a normal "chart node", I came across colinl's post "Using Chart.js to show fully configurable charts in a dashboard template node" (https://flows.nodered.org/flow/c3dc75c47323a2754f5285225bce64b5) in the Node-Red forum.
With the help of a "dropdown-node" I could read in values from different sources, under the topic "Sin".
My problem is the following:
When I change the selection in the "dropdown", the values of the new source are shown before the values of the old sources.
Unfortunately I have no experience with Java and only little experience with Node-Red.
Is there any way to insert a function in the code provided in the forum or perhaps change a value dynamically with a flow.object so that all the old values are removed in the diagram and only the new values are shown?
using the "normal" "chart-node" does allow you to delete all displayed values by sending "", but not to display axis labels. I know I could also just display the axis label above the chart as the chart label, but that doesn't look scientific enough.
I have therefore resorted to the code from "colinl". Since this enables axis labelling with time information on the X-axis.
Unfortunately I can't see through the code to find out on my own what I have to insert in what place in order to also delete all values with a "", as with the "normal" "chart-node".