package com.digitprop.tonic;
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
/** A single-pixel line border, which displays each edge only if that edge does not
* touch the edge of the parent component. This prevents double borders for
* nested components.
*
* This behaviour can be optionally switched on and off by instantiating this
* class with the appropriate constructor parameters.
*
* @author Markus Fischer
*
* This software is under the GNU Lesser General Public License
*/
/*
* ------------------------------------------------------------------------
* Copyright (C) 2004 Markus Fischer
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation.
*
* 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., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*
* You can contact the author at:
* Markus Fischer
* www.digitprop.com
* info@digitprop.com
* ------------------------------------------------------------------------
*/
public class IntelligentLineBorder implements Border
{
/** The color of this border */
private Color color;
/** If true, hide edges touching the parent component's edges */
private boolean isHidingEdges;
/** Creates an instance with BLACK color.
*
* @see #IntelligentLineBorder(Color)
*/
public IntelligentLineBorder()
{
this(Color.BLACK);
}
/** Creates an instance with the specified color.
*
* @param color The color of this border
*/
public IntelligentLineBorder(Color color)
{
this(color, true);
}
/** Creates an instance with BLACK color.
*
* @param isHidingEdges If true, this border is hiding thos edges
* for which the underlying component touches
* an edge of the parent component. Otherwise,
* the border will paint all edges.
*/
public IntelligentLineBorder(boolean isHidingEdges)
{
this(Color.BLACK, isHidingEdges);
}
/** Creates an instance with the specified color.
*
* @param color The color of this border
* @param isHidingEdges If true, this border is hiding thos edges
* for which the underlying component touches
* an edge of the parent component. Otherwise,
* the border will paint all edges.
*/
public IntelligentLineBorder(Color color, boolean isHidingEdges)
{
this.color=color;
this.isHidingEdges=isHidingEdges;
}
/** Returns the insets of this border for the specified component. The insets
* depend upon whether edges of the specified component touch any edges
* of the parent component.
*/
public Insets getBorderInsets(Component c)
{
int left=!isTouchingLeftEdge(c) ? 1 : 0;
int right=!isTouchingRightEdge(c) ? 1 : 0;
int top=!isTouchingTopEdge(c) ? 1 : 0;
int bottom=!isTouchingBottomEdge(c) ? 1 : 0;
return new Insets(top, left, bottom, right);
}
/** Returns true if the specified component's left edge touches
* the left edge of the parent component.
*/
protected boolean isTouchingLeftEdge(Component c)
{
if(!isHidingEdges)
return false;
Component parent=getParent(c);
if(parent==null)
return false;
return c.getX()==c.getParent().getInsets().left;
}
/** Returns true if the specified component's top edge touches
* the top edge of the parent component.
*/
protected boolean isTouchingTopEdge(Component c)
{
if(!isHidingEdges)
return false;
Component parent=getParent(c);
if(parent==null)
return false;
return c.getY()==c.getParent().getInsets().top;
}
/** Returns true if the specified component's right edge touches
* the left edge of the parent component.
*/
protected boolean isTouchingRightEdge(Component c)
{
if(!isHidingEdges)
return false;
Component parent=getParent(c);
if(parent==null)
return false;
return c.getX()+c.getWidth()==c.getParent().getWidth()-c.getParent().getInsets().right;
}
/** Returns true if the specified component's bottom edge touches
* the bottom edge of the parent component.
*/
protected boolean isTouchingBottomEdge(Component c)
{
if(!isHidingEdges)
return false;
Component parent=getParent(c);
if(parent==null)
return false;
return c.getY()+c.getHeight()==c.getParent().getHeight()-c.getParent().getInsets().bottom;
}
/** Returns the parent component for the specified component, or null
* if the parent component could not be found.
*/
protected Component getParent(Component c)
{
Component parent=c.getParent();
while(true)
{
if(parent==null || parent==c)
return null;
if(parent instanceof JComponent)
{
Border border=((JComponent)parent).getBorder();
if(border!=null)
return parent;
}
Component newParent=parent.getParent();
if(newParent==null)
return parent;
else
parent=newParent;
}
}
/** Returns true if this border is opaque */
public boolean isBorderOpaque()
{
return true;
}
/** Paints this border.
*
* @param c The component which contains this border
* @param g The graphics context into which to paint
* @param x The left edge of the border
* @param y The top edge of the border
* @param width The width of the border
* @param height The height of the border
*/
public void paintBorder(Component c, Graphics g, int x, int y, int width, int height)
{
g.setColor(color);
if(!isTouchingLeftEdge(c))
g.drawLine(x, y, x, y+height);
if(!isTouchingTopEdge(c))
g.drawLine(x, y, x+width, y);
if(!isTouchingRightEdge(c))
g.drawLine(x+width-1, y, x+width-1, y+height);
if(!isTouchingBottomEdge(c))
g.drawLine(x, y+height-1, x+width, y+height-1);
}
}
