Re: [ptp-dev] Minimum expected display size for Eclipse user?

["Randy M. Roberts" <rsqrd@xxxxxxxx>]

Interesting!!!!


I took the example from the documentation:
http://help.eclipse.org/help32/nftopic/org.eclipse.platform.doc.isv/reference/api/org/eclipse/swt/custom/ScrolledComposite.html

and added it to the
org.eclipse.ptp.orte.ui.rmLaunchConfiguration.ORTERMLaunchConfigurationDynamicTab.java
code as shown below.

If N_ADDED_CHILDREN is zero then one button from each color
field appears.  Pressing the "add children" button a number of
times will cause scrollbars to appear.  Everything seems to be
acting normally.

If N_ADDED_CHILDREN is set to ten, then ten buttons from each
color field appear, but **NO** scrollbars!!!
If you hit the "add children" button a couple of times, then
the scrollbars **DO** appear and work as expected.

There is something about default/initial sizes that I don't understand.
Any suggestions?  I'm going to continue playing with this.

	public void createControl(Composite parent, IResourceManager rm,
			IPQueue queue) throws CoreException {
		Display display = parent.getDisplay();
		Color red = display.getSystemColor(SWT.COLOR_RED);
		Color blue = display.getSystemColor(SWT.COLOR_BLUE);
//		Shell shell = new Shell (display);
//		shell.setLayout(new FillLayout());

		Composite shell = parent;
		
		numProcsText = new Text(shell, SWT.NONE);

		// set the size of the scrolled content - method 1
		final ScrolledComposite sc1 = new ScrolledComposite(shell,
SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
		final Composite c1 = new Composite(sc1, SWT.NONE);
		sc1.setContent(c1);
		c1.setBackground(red);
		GridLayout layout = new GridLayout();
		layout.numColumns = 4;
		c1.setLayout(layout);
		Button b1 = new Button (c1, SWT.PUSH);
		b1.setText("first button");
		c1.setSize(timesX(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT),2));

		// set the minimum width and height of the scrolled content - method 2
		final ScrolledComposite sc2 = new ScrolledComposite(shell,
SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
		sc2.setExpandHorizontal(true);
		sc2.setExpandVertical(true);
		final Composite c2 = new Composite(sc2, SWT.NONE);
		sc2.setContent(c2);
		c2.setBackground(blue);
		layout = new GridLayout();
		layout.numColumns = 4;
		c2.setLayout(layout);
		Button b2 = new Button (c2, SWT.PUSH);
		b2.setText("first button");
		sc2.setMinSize(timesX(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT),2));

		Button add = new Button (shell, SWT.PUSH);
		add.setText("add children");
		final int[] index = new int[]{0};
		add.addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event e) {
				addChildren(c1, sc2, c2, index);
			}
		});
		
		for (int i=0; i < N_ADDED_CHILDREN; ++i) {
			addChildren(c1, sc2, c2, index);
		}
	}

	private Point timesX(Point computeSize, int d) {
		return new Point(computeSize.x*d, computeSize.y*d);
	}

	/**
	 * @param c1
	 * @param sc2
	 * @param c2
	 * @param index
	 */
	private void addChildren(final Composite c1, final ScrolledComposite
sc2,
			final Composite c2, final int[] index) {
		index[0]++;
		Button button = new Button(c1, SWT.PUSH);
		button.setText("button "+index[0]);
		// reset size of content so children can be seen - method 1
		c1.setSize(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT));
		c1.layout();

		button = new Button(c2, SWT.PUSH);
		button.setText("button "+index[0]);
		// reset the minimum width and height so children can be seen - method
2
		sc2.setMinSize(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT));
		c2.layout();
	}