Bug 180645 Support set format for Date/Time type parameter.[0705]
Description: Support set format for Date/Time type parameter. Build number:2.2.0.v200704031345 Steps to reproduce: 1. New a Date report parameter. 2. Click Change... button to set format for it. Expected result: Can set format for Date/Time parameter. Actual result: Change... button is disabled. Error log:N/A
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/FormatDateTimePage.java
this.category = category;
	}
	/**
	 * Marks the dirty marker of the page.
	 * 
	 * @param dirty
	 */
	private void markDirty( boolean dirty )
	{
		isDirty = dirty;
	}
	private String validatedFmtStr( String fmtStr )
	{
		String text = fmtStr;
		if ( text == null )
		{
			text = PREVIEW_TEXT_INVALID_FORMAT_CODE;
		}
		return text;
	}
	/**
	 * Updates the format Pattern String, and Preview.
	 */
	private void updatePreview( )
	{
		markDirty( hasLoaded );
		String category = getCategory4UIDisplayName( typeChoicer.getText( ) );
		setCategory( category );
		Date sampleDateTime = defaultDate;
		if ( getPreviewText( ) != null