Bug 312859 The list of operator for Chart filter does not provide 30 visible items
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/dialogs/ChartCubeFilterConditionBuilder.java
lb.setText( Messages.getString( "FilterConditionBuilder.text.Condition" ) ); 
		Label lb2 = new Label( anotherParent, SWT.NONE );
		lb2.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		new Label( anotherParent, SWT.NONE );
		Composite condition = new Composite( innerParent, SWT.NONE );
		gd = new GridData( GridData.FILL_BOTH );
		gd.heightHint = 180;
		condition.setLayoutData( gd );
		glayout = new GridLayout( 4, false );
		condition.setLayout( glayout );
		expression = new Combo( condition, SWT.NONE );
		GridData gdata = new GridData( );
		gdata.widthHint = 100;
		expression.setLayoutData( gdata );
		expression.addListener( SWT.Selection, comboModifyListener );
		
		if ( expression.getItemCount( ) == 0 )
		{
			expression.add( DEUtil.resolveNull( null ) );
		}
		expression.addSelectionListener( new SelectionAdapter( ) {
			public void widgetSelected( SelectionEvent e )
			{
				if ( expression.getText( ).equals( VALUE_OF_THIS_DATA_ITEM )
						&& designHandle instanceof DataItemHandle )
				{
					expression.setText( DEUtil.getColumnExpression( ( (DataItemHandle) designHandle ).getResultSetColumn( ) ) );
				}
				updateButtons( );
			}