Using Menus, Toolbars, and Tool Tips

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In this magercise, you will add a working menubar and toolbar, with tool tips, to complete a basic text editor. The editor needs menu options to start working on a new file, open an existing one, save the file, close the window, and display an about box. The toolbar you'll create will need entries for new, open, save, and about with tool tips.

Magercise 6 Prerequisites

Buttons With Icons

Skeleton Code

TextEdit.java

The skeleton code contains the functionality to do the actual work via the following methods:

• doNewCommand()
• doOpenCommand()
• doSaveCommand()
• doAboutCommand()
• doCloseCommand(statusCode)

With the exception of doAboutCommand(), you'll just need to make the necessary connections for event handling. For doAboutCommand(), you'll need to create the necessary JDialog.

Tasks

1. In the TextEdit constructor skeleton, setup the screen to have, from top to bottom, a JToolBar, JTextArea, and JLabel (for status messages). Save a reference to the JTextArea and JLabel in the instance variables pane and statusInfo, respectively, as the event handling methods need access to them. Be sure to place the JTextArea within a JScrollPane to support scrolling.

2. Set the JToolBar to not be floatable so that it cannot be dragged outside the frame.

   If you prefer to have the toolbar floatable, you can skip this step.

3. Create a JMenuBar and add it to the JFrame.

4. Setup the first menu on the JMenuBar. Create a JMenu labeled "File" with JMenuItems under it of "New", "Open", "Save", and "Close". Place a separator between the "Save" and "Close" entries.

5. Add a keyboard mnemonic to each item. Use the first letter of the label.

6. For each JMenuItem, create an anonymous ActionListener to process the event and call the appropriate method to handle the event.
   • New - doNewCommand()
   • Open - doOpenCommand()
   • Save - doSaveCommand()
   • Close - doCloseCommand(statusCode)

7. Add the Help JMenu, with the About JMenuItem. Add a key accelerator for each of 'H' and 'A' respectively. And have the action handler of the About menu item call doAboutCommand().

8. In the doAboutCommand() method, create a modal JDialog named dialog to display the 'About' information. Have the dialog title be "About...". You will need to declare the variable final so it will be usable in the internal event handler.

9. Once the menus are setup, its time to setup the toolbar. Create four JButtons to place on the toolbar, labeled New, Open, Save, and About. Add a separator between Save and About.

10. For each button on the toolbar, add a tooltip, with an appropriate message.

11. For each button, create an anonymous ActionListener to process the event and call the appropriate method to handle the event.

12. Save everything and compile the program. Then run it to see the results.

    As a precautionary behavior, the Save command appends a "1" to the end of the filename you desire to save the file as. This attempts to prevent you from accidently overwriting your source code.

Where help exists, the task numbers above are linked to the step-by-step help page.

The following Java source file represents a solution to this Magercise.

Solution

Magercise 7

Short Course

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