JFace ApplicationWindow：createContents无法正常工作

Question

I'm attempting to create a window that is divided into three parts. A non-resizable header and footer and then a content area that expands to fill the remaining area in the window. To get started, I created the following class:

public class MyWindow extends ApplicationWindow {
    Color white;
    Font mainFont;
    Font headerFont;

    public MyWindow() {
        super(null);
        }

    protected Control createContents(Composite parent) {
        Display currentDisplay = Display.getCurrent();
        white = new Color(currentDisplay, 255, 255, 255);
        mainFont = new Font(currentDisplay, "Tahoma", 8, 0);
        headerFont = new Font(currentDisplay, "Tahoma", 16, 0);

        // Main layout Composites and overall FillLayout
        Composite container = new Composite(parent, SWT.NO_RADIO_GROUP);
        Composite header = new Composite(container, SWT.NO_RADIO_GROUP);
        Composite mainContents = new Composite(container, SWT.NO_RADIO_GROUP);;
        Composite footer = new Composite(container, SWT.NO_RADIO_GROUP);;
        FillLayout containerLayout = new FillLayout(SWT.VERTICAL);
        container.setLayout(containerLayout);

        // Header
        Label headerLabel = new Label(header, SWT.LEFT);
        headerLabel.setText("Header");
        headerLabel.setFont(headerFont);

        // Main contents
        Label contentsLabel = new Label(mainContents, SWT.CENTER);
        contentsLabel.setText("Main Content Here");
        contentsLabel.setFont(mainFont);

        // Footer
        Label footerLabel = new Label(footer, SWT.CENTER);
        footerLabel.setText("Footer Here");
        footerLabel.setFont(mainFont);

        return container;
    }

    public void dispose() {
        cleanUp();
    }

    @Override
    protected void finalize() throws Throwable {
        cleanUp();
        super.finalize();
    }

    private void cleanUp() {
        if (headerFont != null) {
            headerFont.dispose();
        }
        if (mainFont != null) {
            mainFont.dispose();
        }
        if (white != null) {
            white.dispose();
        }
    }
}

And this results in an empty window when I run it like this:

public static void main(String[] args) {
    MyWindow myWindow = new MyWindow();
    myWindow.setBlockOnOpen(true);
    myWindow.open();
    Display.getCurrent().dispose();
}

What am I doing wrong that I don't see three labels the way I'm trying to display them? The createContents code is definitely being called, I can step through it in Eclipse in debug mode.

Answer 1

显然，我需要设置标签的大小和位置才能使其显示。