help using XYAnnotation

[Frank]

has anyone implemented XYAnnotations in an xyplot. can I see how to do so?

[David Gilbert]

Hi Frank,

It is a very basic feature at present, it just allows you to add arbitrary text at some data coordinate:

XYPlot plot = myChart.getXYPlot();
Font font = new Font("SansSerif", Font.PLAIN, 9);
plot.addAnnotation(new XYTextAnnotation("Hello world!", font, 10.0, 75.0));

So in the example above, the text "Hello world!" will be displayed at x = 10.0 and y = 75.0 (as long as your axis ranges include those values).

I plan to extend this feature to allow adding lines, arrows and other shapes to charts, but there are lots of other things to get done first.

Regards,

Dave Gilbert

[Frank]

C:\j2sdk1.4.1_01\bin>javac DSPGraph.java

DSPGraph.java:13: cannot resolve symbol
symbol : class annotations
location: package chart
import com.jrefinery.chart.annotations;
^
DSPGraph.java:229: cannot resolve symbol
symbol : class XYTextAnnotation
location: class DSPGraph
plot.addAnnotation(new XYTextAnnotation("Hello world!", 10.0, 10
.0));
^
2 errors

C:\j2sdk1.4.1_01\bin>

[Frank]

If I
import com.jrefinery.chart.*;

then I still get this:

C:\j2sdk1.4.1_01\bin>javac DSPGraph.java
DSPGraph.java:229: cannot resolve symbol
symbol : class XYTextAnnotation
location: class DSPGraph
plot.addAnnotation(new XYTextAnnotation("Hello world!", 10.0, 10
.0));
^
1 error

C:\j2sdk1.4.1_01\bin>

code looks like this, what you said:

XYPlot plot = chart.getXYPlot();
plot.addAnnotation(new XYTextAnnotation("Hello world!", 10.0, 10.0));

[Greg Rokita]

This feature would be really usefull. Identifing certain points on the graph.
Any idea of when it will be available?

[David Gilbert]

Hi Greg,

The arrows and lines feature falls into the 'easy but not so critical' category. These tasks tend to drop down my priority list, but then one day (often a Friday) I just decide out of the blue that I want to work on something easy and, voila, it's in the next release. But when I work this way, it is hard to predict the schedule.

Regards,

Dave Gilbert

[Antonio Lopes]

Hi David,

I use a TimeSeriesChart graphic to display events occurring within a time frame.
I show a horizontal line (with the method addRangeMarker from XYPlot class) to indicate a average value.
I would like to put a "Annotation" over this average value line.
Do you have any idea of when you're going to have it avaliable?

Thanks,

Antonio Lopes