Bug 192349 The column selected disappears when you reclick the downward arrow [0001]
Description: The column selected disappears when you reclick the downward arrow. Build number: 2.2.0.v20070613-1211 Steps to reproduce: 1, New a table binding to a data set, add an Aggregation, select one column from the "Data Field" dropdown list, click the downward arrow again. Expected result: The column selected is still there. Actual result: The column selected disappears. Error log: N/A
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/BindingDialogHelper.java
Text txtArg = new Text( argsComposite, SWT.BORDER );
					GridData gridData = new GridData( );
					gridData.widthHint = txtFilter.getBounds( ).width - 9;
					txtArg.setLayoutData( gridData );
					createExpressionButton( argsComposite, txtArg );
					argsMap.put( argName, txtArg );
				}
			}
			else
			{
				( (GridData) argsComposite.getLayoutData( ) ).heightHint = 0;
				
			}
		}
		else
		{
			( (GridData) argsComposite.getLayoutData( ) ).heightHint = 0;
			
			
		}
		argsComposite.layout( );
		composite.layout( );
	}
	private void createExpressionButton( final Composite parent, final Text text )
	{
		Button expressionButton = new Button( parent, SWT.PUSH );
		if ( expressionProvider == null )
			expressionProvider = new BindingExpressionProvider( this.bindingHolder );
		UIUtil.setExpressionButtonImage( expressionButton );
		expressionButton.addSelectionListener( new SelectionAdapter( ) {