Constant lines
Constant lines are some of the most useful objects when it
comes to highlighting information in the chart area. You may
want to create constant lines to highlightlimits or specific
points of interest in the chart. For example, in a scientific
application, you may want to use the constant line object
to highlight an alarm limit, or in a financial application
you may want to highlight a target price or date.
Constant lines are lines that you can draw anywhere in the
chart area and associate them with a particular value in the
axis that they're assigned to, as illustrated in the following
figure.

All constant lines are handled by the Line and ConstantLine
classes and their supported members. Using the Line class,
you can control the line color, styles and width. The ContstantLine class members allow control over other attributes such as
the associated axis.
Creating a constant line does not require a new data
series and you can also configure labels and line styles,
colors and width. If you wish to highlight a range of values
instead of a specific value, please refer to the Stripe sample
next in this section.
The following code creates the constant lines for the previous
figure shown.
ConstantLine constantHorz = chart1.getConstantLine(0); constantHorz.setValue(30); constantHorz.setColor(java.awt.Color.red); constantHorz.setAxis(AxisItem.Y); constantHorz.setText("Alarm Limit 1"); constantHorz.setWidth(1); ConstantLine constantVert = chart1.getConstantLine(1); constantVert.setValue(3); constantVert.setColor(java.awt.Color.orange); constantVert.setAxis(AxisItem.X); constantVert.setText("Limit 2"); constantVert.setWidth(3);
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Stripes
Stripes can also be very useful objects to highlight information
in the chart area. They allow you to highlight a range of
values associated with any of the axes by drawing a color
frame in the chart background. For example, in a scientific
application you may want the user to recognize points that
plot between 20 and 80 with a blue stripe object as depicted
in the following figure

The Stripe object handles stripes and
their properties, where you can set color, range and which
axis the stripe is associated to. If you want to highlight a
specific value instead of a range, please refer to the Constant
Lines sample in the previous section.
The following code creates the stripes for the previous figure
shown.
Stripe stripeHorz = chart1.getStripe(0); stripeHorz.setFrom(20); stripeHorz.setTo(50); stripeHorz.setColor(new java.awt.Color(192,192,255,85)); stripeHorz.setAxis(AxisItem.Y); Stripe stripeVert = chart1.getStripe(1); stripeVert.setFrom(3); stripeVert.setTo(5); stripeVert.setColor(new java.awt.Color(128,255,128,85)); stripeVert.setAxis(AxisItem.X);
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