Java JScrollPane Scroll scrollVertically(JComponent c, Rectangle r)

Description

scroll Vertically

License

Apache License

Declaration

public static void scrollVertically(JComponent c, Rectangle r) 

Method Source Code

//package com.java2s;
/* /*w ww .  j  a  v  a 2s  . co m*/
 * Copyright 2003,2004,2005 Colin Crist
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

import java.awt.Component;
import java.awt.Container;

import java.awt.Rectangle;

import javax.swing.JComponent;

import javax.swing.JViewport;

public class Main {
    public static final int VIEWPORT = 0, // take the policy of the viewport
            UNCHANGED = 1, // don't scroll if it fills the visible area, otherwise
            // take the policy of the viewport
            FIRST = 2, // scroll the first part of the region into view
            CENTER = 3, // center the region
            LAST = 4;

    public static void scrollVertically(JComponent c, Rectangle r) {
        scrollVertically(c, r.y, r.y + r.height);
    }

    public static void scrollVertically(JComponent c, int from, int to) {
        Rectangle visible = c.getVisibleRect();

        if (visible.y <= from && visible.y + visible.height >= to)
            return;

        visible.y = from;
        visible.height = to - from;

        c.scrollRectToVisible(visible);
    }

    public static void scrollVertically(JComponent c, Rectangle r, int bias) {
        scrollVertically(c, r.y, r.y + r.height, bias);
    }

    public static void scrollVertically(JComponent c, int from, int to, int bias) {
        Rectangle visible = c.getVisibleRect(), dest = new Rectangle(visible);

        dest.y = from;
        dest.height = to - from;

        if (dest.height > visible.height) {
            if (bias == VIEWPORT) {
                // leave as is
            } else if (bias == UNCHANGED) {
                if (dest.y <= visible.y && dest.y + dest.height >= visible.y + visible.height) {
                    dest.y = visible.y;
                    dest.height = visible.height;
                }
            } else {
                if (bias == CENTER)
                    dest.y += (dest.height - visible.height) / 2;
                else if (bias == LAST)
                    dest.y += dest.height - visible.height;

                dest.height = visible.height;
            }
        }

        if (!visible.contains(dest))
            c.scrollRectToVisible(dest);
    }

    public static void scrollRectToVisible(Component component, Rectangle aRect) {
        Container parent;
        int dx = component.getX(), dy = component.getY();

        for (parent = component.getParent(); parent != null
                && (!(parent instanceof JViewport) || (((JViewport) parent)
                        .getClientProperty("HierarchicalTable.mainViewport") == null)); parent = parent
                                .getParent()) {
            Rectangle bounds = parent.getBounds();

            dx += bounds.x;
            dy += bounds.y;
        }

        if (parent != null) {
            aRect.x += dx;
            aRect.y += dy;

            ((JComponent) parent).scrollRectToVisible(aRect);
            aRect.x -= dx;
            aRect.y -= dy;
        }
    }
}

Related

1. scrollRectLater(final JComponent comp, final Rectangle r)
2. scrollRectToVisible(Component component, Rectangle aRect)
3. scrollToComponent(Component cmp)
4. scrollToVisible(int row, int col)
5. scrollV(String title, JComponent content)
6. scrollView(Component component)