you could set the opacity property when you create your graphic or later on use the setOpacity method of your graphic layer to do that.
You could use the color picker instead? dojox.widget.ColorPicker — The Dojo Toolkit - Reference Guide
Still with RGB alone you can't create transparency, you'll need to alpha as well.
Thanks for the feedback so far. What would be the best solution to allow the user to choose from a variety of colors and have the transparency set at 50 percent? So far, I have the color palette working, yet the graphics are a solid fill. I am looking for something simple.
Thanks for all of the responses. I set a transparency for all graphics, using a opacity of .25. Here is how it turned out:
I'm glad it worked!
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