Steema Central

Posted: **Wed Jun 28, 2023 7:46 am**

Hi,

I have an application where I can write some text on the graph, using the after draw event, and using the TextOut function of the Steema.TeeChart.Drawing.Graphics3DGdiPlus, this works well.
But sometimes, I have so many text to display over the curve that it can be superimposed, and the visibility at the end is not good.
Instead of text lines, I would like to display a simple icon (like a warning icon) or image, just to say to the user that there is something to read at this point. Then, hoovering the icon, a text window (normal form text window) indicating what has to be read on the hovered point.

How can I superimpose these icons over the graph ? Should I draw triangles / redo the warning shapes in the after draw event ?
Then How can I detect the user is hoovering them with the mouse ?

Thanks for your help.
In the attached picture an example of what is done today / what I would like.

Sharkann

: example.jpg (346.28 KiB) Viewed 14858 times

Posted: **Fri Jun 30, 2023 7:19 am**

Hello,

You can render an image in this way:

Code: Select all

private void tChart1_AfterDraw(object sender, Steema.TeeChart.Drawing.Graphics3D g)
{
    Image myIcon = Image.FromFile(@"D:\Data\TCoherence\Publicity\icons\myIcon.png");
    g.Draw(100, 100, myIcon);
 }

Calculate the location as you require. To align it correctly to the axis or other x,y location use the logic as described here:

https://steema.com/docs/teechart/net/tu ... tPanel.htm

To make that appear/disappear with mouse over, the easiest way is to use the TeeChart mousemove event and to check the event X and Y location to the zone of interest,

Code: Select all

private void tChart1_MouseMove(object sender, MouseEventArgs e)
{
  //check e.X and e.Y location to the x,y zone of interest
}

The zone of interest can be obtained as pixel x,y coordinates by converting axis values via the Series CalcXPos method or the Axis CalcPosValue method.

Set a boolean variable, with scope to the form, to true when the mouse is within the zone and provoke a Chart repaint. Use the Boolean in OnAfterDraw to activate (or not) the icon draw line.

Regards,
Marc Meumann

Posted: **Fri Jun 30, 2023 7:25 am**

...one point to add. I described how to make the icon visible or not according to mousemove location. That may have missed the point a little. To actuate a link or "further process" when clicking in the zone, use the mousedown event and confirm that the boolean "zoneTrue" is active to actuate or not your click.

Posted: **Fri Jun 30, 2023 7:25 am**

Thanks so much !
Regards

Steema Central

icons or small images on the graph

icons or small images on the graph

Re: icons or small images on the graph

Re: icons or small images on the graph

Re: icons or small images on the graph