/*
* Copyright 2001 Colin Mummery colin_mummery@yahoo.com Homepage http://www.cellspark.com/vl.html
*
* THIS PROGRAM IS PROVIDED "AS IS" WITHOUT ANY WARRANTIES (OR CONDITIONS),
* EXPRESS OR IMPLIED WITH RESPECT TO THE PROGRAM, INCLUDING THE IMPLIED WARRANTIES (OR CONDITIONS)
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK ARISING OUT OF USE OR
* PERFORMANCE OF THE PROGRAM AND DOCUMENTATION REMAINS WITH THE USER.
*
* Slightly adapted by Simon Thiel
*/
package sit.gui;
import java.awt.*;
import java.util.*;
/**
*
* A vertical layout manager similar to java.awt.FlowLayout.
* Like FlowLayout components do not expand to fill available space except when the horizontal alignment
* is <code>BOTH</code>
* in which case components are stretched horizontally. Unlike FlowLayout, components will not wrap to form another
* column if there isn't enough space vertically. VerticalLayout can optionally anchor components to the top or bottom
* of the display area or center them between the top and bottom.
*
* Revision date 12th July 2001
*
* @author Colin Mummery e-mail: colin_mummery@yahoo.com Homepage:http://www.cellspark.com/vl.html -
* Based on 'FlexLayout' in Java class libraries Vol 2 Chan/Lee Addison-Wesley 1998
*/
public class VerticalLayout implements LayoutManager {
/**
* The horizontal alignment constant that designates centering. Also used to designate center anchoring.
*/
public final static int CENTER = 0;
/**
* The horizontal alignment constant that designates right justification.
*/
public final static int RIGHT = 1;
/**
* The horizontal alignment constant that designates left justification.
*/
public final static int LEFT = 2;
/**
* The horizontal alignment constant that designates stretching the component horizontally.
*/
public final static int BOTH = 3;
/**
* The anchoring constant that designates anchoring to the top of the display area
*/
public final static int TOP = 1;
/**
* The anchoring constant that designates anchoring to the bottom of the display area
*/
public final static int BOTTOM = 2;
private int vgap; //the vertical vgap between components...defaults to 5
private int alignment; //LEFT, RIGHT, CENTER or BOTH...how the components are justified
private int anchor; //TOP, BOTTOM or CENTER ...where are the components positioned in an overlarge space
private Hashtable comps;
//Constructors
/**
* Constructs an instance of VerticalLayout with a vertical vgap of 5 pixels, horizontal centering and anchored to
* the top of the display area.
*/
public VerticalLayout() {
this(5, CENTER, TOP);
}
/**
* Constructs a VerticalLayout instance with horizontal centering, anchored to the top with the specified vgap
*
* @param vgap An int value indicating the vertical seperation of the components
*/
public VerticalLayout(int vgap) {
this(vgap, CENTER, TOP);
}
/**
* Constructs a VerticalLayout instance anchored to the top with the specified vgap and horizontal alignment
*
* @param vgap An int value indicating the vertical seperation of the components
* @param alignment An int value which is one of <code>RIGHT, LEFT, CENTER, BOTH</code> for the horizontal alignment.
*/
public VerticalLayout(int vgap, int alignment) {
this(vgap, alignment, TOP);
}
/**
* Constructs a VerticalLayout instance with the specified vgap, horizontal alignment and anchoring
*
* @param vgap An int value indicating the vertical seperation of the components
* @param alignment An int value which is one of <code>RIGHT, LEFT, CENTER, BOTH</code> for the horizontal alignment.
* @param anchor An int value which is one of <code>TOP, BOTTOM, CENTER</code> indicating where the components are
* to appear if the display area exceeds the minimum necessary.
*/
public VerticalLayout(int vgap, int alignment, int anchor) {
this.vgap = vgap;
this.alignment = alignment;
this.anchor = anchor;
}
//----------------------------------------------------------------------------
private Dimension layoutSize(Container parent, boolean minimum) {
Dimension dim = new Dimension(0, 0);
Dimension d;
synchronized (parent.getTreeLock()) {
int n = parent.getComponentCount();
for (int i = 0; i < n; i++) {
Component c = parent.getComponent(i);
if (c.isVisible()) {
d = minimum ? c.getMinimumSize() : c.getPreferredSize();
dim.width = Math.max(dim.width, d.width);
dim.height += d.height;
if (i > 0) {
dim.height += vgap;
}
}
}
}
Insets insets = parent.getInsets();
dim.width += insets.left + insets.right;
dim.height += insets.top + insets.bottom + vgap + vgap;
return dim;
}
//-----------------------------------------------------------------------------
/**
* Lays out the container.
*/
public void layoutContainer(Container parent) {
Insets insets = parent.getInsets();
synchronized (parent.getTreeLock()) {
int n = parent.getComponentCount();
Dimension pd = parent.getSize();
int y = 0;
//work out the total size
for (int i = 0; i < n; i++) {
Component c = parent.getComponent(i);
Dimension d = c.getPreferredSize();
y += d.height + vgap;
}
y -= vgap; //otherwise there's a vgap too many
//Work out the anchor paint
if (anchor == TOP) {
y = insets.top;
} else if (anchor == CENTER) {
y = (pd.height - y) / 2;
} else {
y = pd.height - y - insets.bottom;
}
//do layout
for (int i = 0; i < n; i++) {
Component c = parent.getComponent(i);
Dimension d = c.getPreferredSize();
int x = insets.left;
int wid = d.width;
if (alignment == CENTER) {
x = (pd.width - d.width) / 2;
} else if (alignment == RIGHT) {
x = pd.width - d.width - insets.right;
} else if (alignment == BOTH) {
wid = pd.width - insets.left - insets.right;
}
c.setBounds(x, y, wid, d.height);
if(c.isVisible()){
y += d.height + vgap;
}//else stick with the old y - value to avoid empty space for
//invisible components
}
}
}
//-----------------------------------------------------------------------------
public Dimension minimumLayoutSize(Container parent) {
return layoutSize(parent, false);
}
//-----------------------------------------------------------------------------
public Dimension preferredLayoutSize(Container parent) {
return layoutSize(parent, false);
}
//----------------------------------------------------------------------------
/**
* Not used by this class
*/
public void addLayoutComponent(String name, Component comp) {
}
//-----------------------------------------------------------------------------
/**
* Not used by this class
*/
public void removeLayoutComponent(Component comp) {
}
//-----------------------------------------------------------------------------
public String toString() {
return getClass().getName() + "[vgap=" + vgap + " align=" + alignment + " anchor=" + anchor + "]";
}
}