How to stop JFace combo box from re sizing on a window re size?

Question

I have a Java Eclipse RCP program in which I have a a long string inside a JFace combobox. Now when I am in the same view,The combobox attaches a scroll over it to show the

Answer 1

If you are using GridLayout and GridData as your layout you can specify a value in the widthHint field to suggest the width for the Combo.

GridData data = new GridData(SWT.FILL, SWT.CENTER, true, false);

data.widthHint = 100;

preferredResourceCombo.setLayoutData(data);

Using a fixed value like this might cause problems if the user uses a large font. So an alternative way of calculating the width is to use Dialog.convertWidthInCharsToPixels:

GC gc = new GC(control);
gc.setFont(control.getFont());
FontMetrics fontMetrics = gc.getFontMetrics();
gc.dispose();

data.widthHint = Dialog.convertWidthInCharsToPixels(fontMetrics, charCount);

If your code is in a Dialog you can simplify this to just:

data.widthHint = convertWidthInCharsToPixels(charCount);