How to get the FlSpot touched in fl_charts - flutter

I have a LineChart where the default behaviour is that a tooltip with the y value shows up when you touch the chart.
How would i be able to get the x and y values of the point touched on the chart to save it in a variable for example.
It has to be in this property of the LineChart:
lineTouchData: LineTouchData(enabled: true),

Related

Put Axis Range label above in am4charts

I have a am4charts (v5) chart with a bars and a line (made with axis range), but i cannot put the axis range label above series line.
I tried with above param, with zIndex, but i cannot make it work.
I put the above param here in the axis range creation
let seriesRangeDataItem = yAxis.makeDataItem({ value: value, endValue: value, above: true});
This code reproduce the problem
https://codepen.io/javierflti/pen/wvxKRWo
As you can see, label "120" is not above bars
Any idea?
Thanks

How to set correct image dimensions by LatLngBounds using ImageOverlay?

I want to use ImageOverlays as markers, because I want the images to scale with zoom. Markers icons always resize to keep their size the same when you zoom.
My problem is that I can't figure out how to transform pixels to cords, so my image isn't stretched.
For instance, I decided my south-west LatLng to be [50, 50]. My image dimensions are 24px/24px.
How do I calculate the north-east LatLng based on the image pixels?
You are probably looking for map conversion methods.
In particular, you could use:
latLngToContainerPoint: Given a geographical coordinate, returns the corresponding pixel coordinate relative to the map container.
containerPointToLatLng: Given a pixel coordinate relative to the map container, returns the corresponding geographical coordinate (for the current zoom level).
// 1) Convert LatLng into container pixel position.
var originPoint = map.latLngToContainerPoint(originLatLng);
// 2) Add the image pixel dimensions.
// Positive x to go right (East).
// Negative y to go up (North).
var nextCornerPoint = originPoint.add({x: 24, y: -24});
// 3) Convert back into LatLng.
var nextCornerLatLng = map.containerPointToLatLng(nextCornerPoint);
var imageOverlay = L.imageOverlay(
'path/to/image',
[originLatLng, nextCornerLatLng]
).addTo(map);
Demo: http://playground-leaflet.rhcloud.com/tehi/1/edit?html,output

JAVAFX CHARTS: Setting origin point on category axis

I am in need to add a zero point for category axis in javafx line chart. In the image I want some "T0" to represent the zero mark of origin on the x axis, so that I can mark point on y axis as on the chart.
sample line chart ( looks like bar chart !)
I'm not completely clear what you're asking, but if you want the pixel coordinates of the left end of the x-axis, you can do
Category xAxis = ... ;
// ...
double leftEnd = xAxis.getDisplayPosition(value0) - xAxis.getCategorySpacing();
where value0 is the x-value of the first data point.

How do I add a units label to a ILNumerics Colorbar

I would like to display the units in text for the values displayed on the colorbar. I have a colorbar added to my ILSurface and I'd like to show my units in text on the color bar along with the range.
Edit: I want to display text at the bottom of the color bar below the bottom tick just the one label.
I was able to get this to work this way
new ILColorbar()
{
Children = { new ILLabel("nm") {Position = new Vector3(.2f,.98f,0) } }
}
I have to say the Position coordinates are not very intuitive. I had to basically adjust the numbers by trial and error until it fit. I knew that the values range 0..1 so the X value was 1 at the bottom but I wanted it up from the border. And the Y value would need to be indented in some but I wasn't sure what was a good value but .2 works.
You can access the axis of ILColorbar and configure it in the usual way. Use the LabelTransformFunc on the ticks to set your own label text. You can use the default transform func and add your unit string.
Example:
var cb = scene.First<ILColorbar>();
cb.Axis.Ticks.LabelTransformFunc = (ind, val) =>
{
return ILTickCollection.DefaultLabelTransformFunc(ind, val) + "nm";
};
You can read more about the axis configuration here:
Axis Configuration
LabelTransformFunc in ApiDoc
Edit:
If only one label is needed, then add a new ILLabel object in ILColorbar group as follows:
new ILColorbar() {
new ILLabel("z(nm)") {
Position = new Vector3(0.5,1,0),
Anchor = new PointF(0.5f,0)
}
}
The ILColorbar area have the relative coordinates 0..1 over the width and the height of the color bar. So we set position x in the middle of the ILColorbar, and position y at the bottom.
The Anchor position is used as relative position in relation to the Position point.
ILLabel Documentation

Second Y axis in GWT Highcharts on a stock chart?

I'm trying to add a second Y axis to a StockChart with the Moxieapps Highcharts wrapper, but without success. I need to add a new axis on the right side of the chart, and would expect the following code to work:
StockChart chart = new StockChart();
YAxis firstYAxis = chart.getYAxis(0);
firstYAxis.setAxisTitleText("First Y axis");
Series firstSeries = chart.createSeries();
firstSeries.setPoints(/* Imagine lots of points. */);
firstSeries.setYAxis(0); // Not required since 0 is the default Y axis.
chart.addSeries(firstSeries);
YAxis secondYAxis = chart.getYAxis(1);
secondAxis.setOpposite(true); // *Should* put the axis on the right side.
secondYAxis.setAxisTitleText("Second Y axis");
Series secondSeries = chart.createSeries();
secondSeries.setPoints(/* Imagine lots of points. */);
secondSeries.setYAxis(1); // *Should* add the series to the second Y axis.
chart.addSeries(secondSeries);
// Somehow the second series ends up being in the navigator...
chart.setOption("navigator/enabled", true);
chart.setOption("scrollbar/enabled", true);
add(chart);
The second Y axis does not even render. If I don't add the second series to the second Y axis, it shows up (as expected) as values on the first Y axis.
Has anyone successfully added multiple Y axes on a StockChart, that can tell me what I'm doing wrong here? Thanks a lot in advance!
I had the same problem and it seems that GWT-HighCharts is the problem. You must create YAxises manually via native calls. Here is the solution;
HighCharts Stock Chart error code 18