Linechart - no dataset displayed

[howudodat]

Just getting started using this in a GWT/dominokit project. I will be retrieving fft signal data from a db and then plotting it. The below code is just a simple test. I get the chart and the red legend, the axis is scaled down to about -60 and the title changes, but no line is drawn.

         protected void initUI() {
		Charba.enable();
		chart = new LineChart();
		
		chart.getOptions().setResponsive(true);
		chart.getOptions().getLegend().setPosition(Position.TOP);
		chart.getOptions().getTitle().setDisplay(true);
		chart.getOptions().getTitle().setText("Charba line chart");
		
		this.getContentElement().element().appendChild(chart.getChartElement().as());
		testChart();
	}
	
	protected void testChart() {
		LinkedList<Double> l = new LinkedList<>();
		l.add(-45.1);
		l.add(-42.1);
		l.add(-45.1);
		l.add(-39.1);
		
		LineDataset dataset = new LineDataset();
		dataset.setData(l);
		dataset.setBackgroundColor(HtmlColor.RED);
		chart.getData().setDatasets(dataset);
		chart.getOptions().getTitle().setText("Test");
		chart.update();
	}

UPDATE: the problem appears to be that we dont have any labels set. We will probably only set about 5 labels, but we will have 200+ points of data. This is a frequency plot and there will not be enough room to display all the labels

UPDATE2: This is getting uglier. If I set 3 labels, only 3 points are plotted. What I really would like is something like: labels["0", "50", "100"] and they be spaced at the start, middle and end, but all of the points get plotted.

[howudodat]

ok, quick code to help anyone that might follow

		CartesianCategoryAxis axis1 = new CartesianCategoryAxis(chart);
		axis1.setDisplay(true);
		axis1.getTitle().setDisplay(false);
		axis1.getTicks().setCallback(new CategoryTickCallback() {
			@Override
			public String onCallback(Axis axis, String value, int index, List<String> values) {
				return "";
			}
		});
		chart.getOptions().getScales().setAxes(axis1);

[stockiNail]

@howudodat the data to load in a chart should have always 2 dimensions, for cartesian axes as you are using.

• value: the value of dataset that you want to show (line chart has cartesian linear axis as default). The values can be usually set in a dataset by setData method .
• index: the value to show on index axis, which are represented by ticks. The index can be usually set by chart.getData().setLabel or in a dataset by setLabels method .

Furthermore you can DataPoint (with x and y properties), avoiding to set labels where for each value you have a specific index.

In the example, the value is set as list of numbers but the index is missing, therefore the line is not drawn.

The code that you published, all ticks (related to the index) are not showed .

To have a clear picture about your expected result, can you publish here how the chart should look like?
In this case I can prepare a sample and published here, if you want.

I'm glad you are using Charba on DominoKit. Let me know, if you want, how it's working because I haven't tested it yet.