Re: setting constant map properties

Hi Jim,

It will probably be easiest if you save your DataReferences
in your own arrays or Vectors. You can remove them from the
DisplayImpl by a call to removeReference(), then add again
with the new ConstantMap values.

Some of the other folks on the list have written complex
applications that may do something like this - perhaps they
can add to this?

Good luck,
Bill

On Fri, 12 Dec 2003, Jim Cookas wrote:

> hello
>
> i am currently developing a line/image plotting application for radar 
> analysis using visad...i am relatively new to the package, but thus far i 
> have been quite pleased...here is my problem:
>
> basically i want to allow the user change various properties of each line 
> that is currently displayed in the plot...i have created my own java widgets 
> for this and they control color, width, and style...i add each data set to 
> the display like this (the data is added with default display properties to 
> be changed later by the user):
>
>
> dataRef = new DataReferenceImpl("dataRef");  // dataRef is local
> dataRef.setData(field);  // 'field' (local) is populated with data from a 
> text file
>
> ConstantMap[] lineCMap = {
>       new ConstantMap(redVal, Display.Red),
>       new ConstantMap(greenVal, Display.Green),
>       new ConstantMap(blueVal, Display.Blue),
>       new ConstantMap(GraphicsModeControl.SOLID_STYLE, Display.LineStyle),
>       new ConstantMap(1.0f, Display.LineWidth) };
>
> _display.addReference(dataRef, lineCMap);  // '_display' is a member of my 
> plotter class
>
>
> i am not storing the data references anywhere else in the class...in theory, 
> i thought i could grab the data reference i need from the _display, change 
> the constant maps (according to user-specified values), and pass it back to 
> the display...here is some pseudo-code:
>
>
> void listener() {
>       // get appropriate data reference from _display
>
>       // create new constant maps with user-specified values
>
>       // swap out the old data reference (and old constant maps) with new 
> data reference (and new constant maps)
> }
>
>
> the other idea was maybe to replace the constant maps for the requested data 
> reference...is this possible?...i cannot seem to figure out how to do 
> this...i have read documentation everywhere and looked at many examples...
>
> many thanks in advance for any help!
>
> jc
>
>