Center Layout : Custom Layout « Swing « Java Tutorial






/*
    GNU LESSER GENERAL PUBLIC LICENSE
    Copyright (C) 2006 The Lobo Project

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Contact info: lobochief@users.sourceforge.net
*/
/*
 * Created on Mar 19, 2005
 */

import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.LayoutManager;

/**
 * @author J. H. S.
 */
public class CenterLayout implements LayoutManager {
    public void addLayoutComponent(String arg0, Component arg1) {
    }

    public void removeLayoutComponent(Component arg0) {
    }

    public Dimension preferredLayoutSize(Container arg0) {
      java.awt.Insets insets = arg0.getInsets();
        int count = arg0.getComponentCount();
        if(count > 0) {
            Dimension d = arg0.getComponent(0).getPreferredSize();
            return new Dimension(d.width + insets.left + insets.right,
                           d.height + insets.top + insets.bottom);
        }
        else {
            return new Dimension(insets.left + insets.right, insets.top + insets.bottom);
        }
    }

    /* (non-Javadoc)
     * @see java.awt.LayoutManager#minimumLayoutSize(java.awt.Container)
     */
    public Dimension minimumLayoutSize(Container arg0) {
      java.awt.Insets insets = arg0.getInsets();
        int count = arg0.getComponentCount();
        if(count > 0) {
            Dimension d = arg0.getComponent(0).getMinimumSize();
            return new Dimension(d.width + insets.left + insets.right,
               d.height + insets.top + insets.bottom);
        }
        else {
            return new Dimension(insets.left + insets.right, insets.top + insets.bottom);
        }
    }

    /* (non-Javadoc)
     * @see java.awt.LayoutManager#layoutContainer(java.awt.Container)
     */
    public void layoutContainer(Container container) {
        int count = container.getComponentCount();
        if(count > 0) {
            Component child = container.getComponent(0); 
            java.awt.Insets insets = container.getInsets();
            int availWidth = container.getWidth() - insets.left - insets.right;
            int availHeight = container.getHeight() - insets.top - insets.bottom;
            Dimension preferredSize = child.getPreferredSize();
            double preferredWidth = preferredSize.getWidth();
            double preferredHeight = preferredSize.getHeight();
            int width;
            int height;
            int x;
            int y;
            if(preferredWidth < availWidth) {
              x = (int) Math.round(insets.left + (availWidth - preferredWidth) / 2);
              width = (int) Math.round(preferredWidth);
            }
            else {
              x = insets.left;
              width = availWidth;
            }
            if(preferredHeight < availHeight) {
              y = (int) Math.round(insets.top + (availHeight - preferredHeight) / 2);
              height = (int) Math.round(preferredHeight);
            }
            else {
              y = insets.top;
              height = availHeight;
            }
            child.setBounds(x, y, width, height);
        }
    }
    
    private static CenterLayout instance = new CenterLayout();
    
    public static CenterLayout getInstance() {
      return instance;
    }
}








14.97.Custom Layout
14.97.1.Custom Layout: DiagonalLayoutCustom Layout: DiagonalLayout
14.97.2.GraphPaperLayout implements LayoutManager2
14.97.3.Circle Layout
14.97.4.This LayoutManager arranges the components into a column. Components are always given their preferred size
14.97.5.Compents are laid out in a circle.
14.97.6.Specialised layout manager for a grid of components.
14.97.7.Stack Layout, uses an orientation to determine if the contents should be arranged horizontally or vertically.
14.97.8.A layout manager that displays a single component in the center of its container.
14.97.9.A simple layoutmanager to overlay all components of a parent.
14.97.10.A layout manager that lays out components along a central axis
14.97.11.Wrapper Layout
14.97.12.Center Layout
14.97.13.DividerLayout is layout that divides two components with the column of actions
14.97.14.X Y Layout