Recipe 13.2 Customizing a Wizard

13.2.1 Problem

You want to customize a template you created for a plug-in that includes a wizard.

13.2.2 Solution

Edit the wizard's support file (SampleNewWizard.java in the example created in the previous recipe) to customize the code.

13.2.3 Discussion

In the plug-in created in the previous recipe, the wizard creates files with the default name document.new, inserting default text into those files. This wizard is supported by the two files SampleNewWizard.java and SampleNewWizardPage.java. In SampleNewWizard.java, the code begins by creating the page the wizard will show:

public class SampleNewWizard extends Wizard implements INewWizard {
    private SampleNewWizardPage page;
    private ISelection selection;

    /**
     * Constructor for SampleNewWizard.
     */
    public SampleNewWizard( ) {
        super( );
        setNeedsProgressMonitor(true);
    }
    
    /**
     * Adding the page to the wizard.
     */

    public void addPages( ) {
        page = new SampleNewWizardPage(selection);
        addPage(page);
    }
        .
        .
        .

In the createControl method of SampleNewWizardPage.java, the wizard's appearance is created. As you can see here, the SWT controls—labels, text controls, and so on—are added and positioned:

public void createControl(Composite parent) {
    Composite container = new Composite(parent, SWT.NULL);
    GridLayout layout = new GridLayout( );
    container.setLayout(layout);
    layout.numColumns = 3;
    layout.verticalSpacing = 9;
    Label label = new Label(container, SWT.NULL);
    label.setText("&Container:");

    containerText = new Text(container, SWT.BORDER | SWT.SINGLE);
    GridData gd = new GridData(GridData.FILL_HORIZONTAL);
    containerText.setLayoutData(gd);
    containerText.addModifyListener(new ModifyListener( ) {
        public void modifyText(ModifyEvent e) {
            dialogChanged( );
        }
    });

    Button button = new Button(container, SWT.PUSH);
    button.setText("Browse...");
    button.addSelectionListener(new SelectionAdapter( ) {
        public void widgetSelected(SelectionEvent e) {
            handleBrowse( );
        }
    });
    label = new Label(container, SWT.NULL);
    label.setText("&File name:");

    fileText = new Text(container, SWT.BORDER | SWT.SINGLE);
    gd = new GridData(GridData.FILL_HORIZONTAL);
    fileText.setLayoutData(gd);
    fileText.addModifyListener(new ModifyListener( ) {
        public void modifyText(ModifyEvent e) {
            dialogChanged( );
        }
    });
    initialize( );
    dialogChanged( );
    setControl(container);
}

If you want to customize the wizard's page, do it here. This is where that page is created; if you want a different appearance and different controls, this is the place to configure things as you want them.

The actual work that the wizard does for your plug-in begins when the Finish button is clicked in the wizard's page, calling the doFinish method in SampleNewWizard.java. We'll customize this code to insert our own text into the newly created document. That method runs in a worker thread, and it begins by finding the path of the file to create and creates that file this way; if you want to create files in another location, this is the spot to customize:

private void doFinish(
    String containerName,
    String fileName,
    IProgressMonitor monitor)
    throws CoreException {
     // create a sample file
     monitor.beginTask("Creating " + fileName, 2);
     IWorkspaceRoot root = ResourcesPlugin.getWorkspace( ).getRoot( );
     IResource resource = root.findMember(new Path(containerName));
     if (!resource.exists( ) || !(resource instanceof IContainer)) {
         throwCoreException("Container \"" + containerName + 
        "\" does not exist.");
    }
    IContainer container = (IContainer) resource;
    final IFile file = container.getFile(new Path(fileName));
        .
        .
        .

To set the contents of the new file, the code next calls a method named openContentStream and uses that method to fill the file:

try {
    InputStream stream = openContentStream( );
    if (file.exists( )) {
        file.setContents(stream, true, true, monitor);
    } else {
        file.create(stream, true, monitor);
    }
    stream.close( );
              .
              .
              .

We'll customize the openContentStream method to change the default text put into the document.new file created by the wizard. Here's what that method looks like now:

private InputStream openContentStream( ) {
    String contents =
     "This is the initial file contents for *.new file that should 
              be word-sorted in the Preview page of the multi-page editor";
    return new ByteArrayInputStream(contents.getBytes( ));
}

Change that to this, where we're installing our own custom text:

private InputStream openContentStream( ) {
    String contents =
     "Welcome to document.new";
    return new ByteArrayInputStream(contents.getBytes( ));
}

Making this change customizes the wizard for our purposes. In Recipe 13.3, we will customize the editor this plug-in displays.

13.2.4 See Also

Recipe 13.1 on creating plug-ins that support wizards and editors; Recipe 13.3 on customizing an editor.