Activity 6.3 - Simulating a control panel in a lift

Topic

In this activity we build up a more complex window design by nesting several JPanels in the content pane.

Task

You are asked to write a program that will simulate the control panel in a lift. Here is a sketch the designer has drawn.

On the content pane there are three panels.

• The top panel holds two text fields, the first to show whether the lift is travelling up or down, the second to indicate the current floor, and an alarm button.
• The middle panel contains buttons for the floors.
• The bottom panel contains buttons for opening and closing the doors. (These just use the < and > characters from the keyboard.)

The design uses a standard title bar, with title "Lift controls".

Notes

The text fields should be four and two characters wide respectively. For the purposes of this prototype they can just be left blank. To create a JTextField of the desired width use the constructor

JTextField(int columns) 

A JTextField is added to a panel in exactly the same way as we add a JButton.

Instructions

1. Create a new project called MyEx6_3 in the Unit 6 folder. In the New Java Application wizard name the Main Class myex6_3.LiftButtonFrameTest.
2. Add a new Java class LiftButtonFrame to the project. Complete the coding for this class so that when an instance of LiftButtonFrame is displayed it will appear as in the design sketch above.
3. Complete the main class LiftButtonFrameTest so it creates a test instance of LiftButtonFrame and makes it visible. Compile and run your project.
4. Our specimen solution can be found in the Solution file.