gauge.js

[Charley]

You may need a start!

start: function () {
    
},

[sispheor]

@Charley yes, I haven’t shown it but it’s present.

[Charley]

What is the code in your start.
I expect you don’t add the wrapper to the dom

[sispheor]

@Charley here is the code
https://github.com/Sispheor/MMM-BMP-sensor/blob/dev/MMM-BMP-sensor.js

[Charley]

@sispheor Is everything invisible or just the gauge?
Do you see pressure or temperatures?
What is in your console.log from

console.log('adafruit_python_bpm.py results: %j', results[0]);

[sispheor]

@Charley Yes the table is visible. Only the gauge doesn’t appear.

[Charley]

Okay I might have an idea

Change your createElement part to

let mycanvas = document.createElement("div");
mycanvas.id=("divcanvas")
let target=document.getElementById("divcanvas")

[sispheor]

@Charley OK thanks, I’ll try this in a couple minutes.

[sispheor]

@Charley Doesn’t work…

Uncaught TypeError: Cannot read property 'getContext' of null

[Charley]

Maybe you could try this

let mycanvas = document.createElement("canvas");   // changed from div to canvas
mycanvas.id=("divcanvas")
let target=document.getElementById("divcanvas")

I made a typo yesterday

[sispheor]

@Charley yes it’s what I tried…

[sispheor]

I tried with another lib called canvas-gauges. It’s the same. The canvas doesn’t appear on the screen

I’m wondering if a parent CSS config or something like could be the reason.

[sispheor]

It’s good it works!! For the last lib I just forgot to call the draw method.