This is a small library for your Android application to enable the users to select an arbitrary color. I've abstracted this to a widget that can be added to any View.
Java

README

Android Color Picker
aka AmbilWarna library ("Pick a Color" in Indonesian)

This is a small library for your application to enable the users to select an arbitrary color. It is currently used in the free Bible applications for Android (http://androidbible.blogspot.com). It is also used by the >250,000 downloads app DigiClock Widget.

For example, your application has a feature to customize the color of some background, text, or maybe for a painting application where the user should be able to select different color for painting or filling.

Screenshot:
http://lh5.ggpht.com/_ODdyLCCXPpQ/TKsFBMSlhdI/AAAAAAAAu6o/vqpGqyCnywY/s800/r230-ambilwarna.png

This is an Android Library Project where you can include it into your main project.

How to use
Create a color picker dialog by calling the following constructor, and then show it.

AmbilWarnaDialog(Context context, int color, OnAmbilWarnaListener listener)
as follows:

    // initialColor is the initially-selected color to be shown 
    // in the rectangle on the left of the arrow.
    // for example, 0xff000000 is black, 0xff0000ff is blue. 
    // Please be aware of the initial 0xff which is the alpha.
    AmbilWarnaDialog dialog = AmbilWarnaDialog(this, initialColor,
            new OnAmbilWarnaListener() {
        @Override
        public void onOk(AmbilWarnaDialog dialog, int color) {
                // color is the color selected by the user.
        }
                
        @Override
        public void onCancel(AmbilWarnaDialog dialog) {
                // cancel was selected by the user
        }
    });

    dialog.show();

Contributors
Pascal Cans (noobs.com)

See also other projects for Android:

Context Menu with Icons
http://code.google.com/p/android-icon-context-menu/