Task: Write a Colour Chooser Applet that allows the user to choose a colour to be displayed, using the scrollbars or by entering the values directly. The applet should check that the user has not inputted invalid values. Figure 9.21, “The Colour Chooser Applet Exercise” shows my user-interface and you can see it working here - ColorChooserApplet.html.

Figure 9.21. The Colour Chooser Applet Exercise

Hints: Use a Canvas object for the coloured rectangle. Initially get the applet working with the scrollbars only and then try the text fields. The text fields are tricky as the user could enter something like "asdf". Fortunately the Integer class constructor that accepts a String parameter throws a NumberFormatException when an invalid value is passed.