vaadin-framework/src/com/vaadin/demo/coverflow/Coverflow.java

/* 
@ITMillApache2LicenseForJavaFiles@
 */

package com.vaadin.demo.coverflow;

import com.vaadin.demo.coverflow.gwt.client.ui.VCoverflow;
import com.vaadin.terminal.PaintException;
import com.vaadin.terminal.PaintTarget;
import com.vaadin.ui.AbstractSelect;
import com.vaadin.ui.ClientWidget;

@SuppressWarnings( { "serial", "unchecked" })
@ClientWidget(VCoverflow.class)
public class Coverflow extends AbstractSelect {

    private String backgroundGradientStart = "FFFFFF";
    private String backgroundGradientEnd = "EEEEEE";
    private boolean scrollbarVisibility = true;

    @Override
    public String getTag() {
        return "cover";
    }

    /**
     * Paints the uidl
     * 
     * @param PaintTarget
     *            target
     * @throws PaintException
     */
    @Override
    public void paintContent(PaintTarget target) throws PaintException {
        // Superclass writes any common attributes in the paint target.
        super.paintContent(target);

        target.addAttribute("backgroundGradientStart", backgroundGradientStart);
        target.addAttribute("backgroundGradientEnd", backgroundGradientEnd);
        target.addAttribute("scrollbarVisibility", scrollbarVisibility);
    }

    /**
     * The user can specify a background gradient for the coverflow. The input
     * values are RGB values for the start and end gradients.
     * 
     * @param int startR
     * @param int startG
     * @param int startB
     * @param int endR
     * @param int endG
     * @param int endB
     */
    public void setBackgroundColor(int startR, int startG, int startB,
            int endR, int endG, int endB) {
        backgroundGradientStart = "";
        backgroundGradientEnd = "";

        // Convert all integers to hexadecimal format and make sure they are two
        // characters long (in other words, add a zero in front if the value is
        // less than 16 => 0x0F)
        if (startR < 16) {
            backgroundGradientStart += "0";
        }
        backgroundGradientStart += Integer.toHexString(Math.max(Math.min(
                startR, 255), 0));

        if (startG < 16) {
            backgroundGradientStart += "0";
        }
        backgroundGradientStart += Integer.toHexString(Math.max(Math.min(
                startG, 255), 0));

        if (startB < 16) {
            backgroundGradientStart += "0";
        }
        backgroundGradientStart += Integer.toHexString(Math.max(Math.min(
                startB, 255), 0));

        if (endR < 16) {
            backgroundGradientEnd += "0";
        }
        backgroundGradientEnd += Integer.toHexString(Math.max(Math.min(endR,
                255), 0));

        if (endG < 16) {
            backgroundGradientEnd += "0";
        }
        backgroundGradientEnd += Integer.toHexString(Math.max(Math.min(endG,
                255), 0));

        if (endB < 16) {
            backgroundGradientEnd += "0";
        }
        backgroundGradientEnd += Integer.toHexString(Math.max(Math.min(endB,
                255), 0));

        requestRepaint();
    }

    /**
     * The user can toggle the visibility of the scrollbar
     * 
     * @param boolean visible
     */
    public void setScrollbarVisibility(boolean visible) {
        if (scrollbarVisibility != visible) {
            scrollbarVisibility = visible;
            requestRepaint();
        }
    }

}