splitterbar.java

Java program shows how to use tab control for jumping between multiple layouts.

package com.magelang.splitter;

import java.awt.*;
import java.awt.event.*;
import com.magelang.Colors;

/** A class that implements a splitter bar.  It is only intended to be used
 *	in a SplitterLayout.  Because it is dervied from Panel, a SplitterBar
 *	can do anything a normal panel can do.  However, if you add any
 *	components to this panel, the scroll handle will not be accessible.  In a
 *	case like this, you need to explicitly add a SplitterSpace component to the
 *	SplitterBar, guaranteeing a place for the handle to be available.
 *
 * <p>Use this code at your own risk!  MageLang Institute is not
 * responsible for any damage caused directly or indirctly through
 * use of this code.
 * <p><p>
 * <b>SOFTWARE RIGHTS</b>
 * <p>
 * MageLang support classes, version 1.0, MageLang Institute
 * <p>
 * We reserve no legal rights to this code--it is fully in the
 * public domain. An individual or company may do whatever
 * they wish with source code distributed with it, including
 * including the incorporation of it into commerical software.
 *
 * <p>However, this code cannot be sold as a standalone product.
 * <p>
 * We encourage users to develop software with this code. However,
 * we do ask that credit is given to us for developing it
 * By "credit", we mean that if you use these components or
 * incorporate any source code into one of your programs
 * (commercial product, research project, or otherwise) that
 * you acknowledge this fact somewhere in the documentation,
 * research report, etc... If you like these components and have
 * developed a nice tool with the output, please mention that
 * you developed it using these components. In addition, we ask that
 * the headers remain intact in our source code. As long as these
 * guidelines are kept, we expect to continue enhancing this
 * system and expect to make other tools available as they are
 * completed.
 * <p>
 * The MageLang Support Classes Gang:
 * @version MageLang Support Classes 1.0, MageLang Insitute, 1997
 * @author <a href="http:www.scruz.net/~thetick">Scott Stanchfield</a>, <a href=http://www.MageLang.com>MageLang Institute</a>
 *	@see SplitterLayout
 *	@see SplitterSpace
*/
public class SplitterBar extends Panel {
	static final Cursor VERT_CURSOR = new Cursor(Cursor.N_RESIZE_CURSOR);
	static final Cursor HORIZ_CURSOR = new Cursor(Cursor.E_RESIZE_CURSOR);
	static final Cursor DEF_CURSOR = new Cursor(Cursor.DEFAULT_CURSOR);
	private int orientation = SplitterLayout.VERTICAL;
	
	private boolean alreadyDrawn = false;
	private Rectangle originalBounds=null;
	private Window wBar;
	private boolean mouseInside=false;
	
	/** Creates a new SpliiterBar */
	public SplitterBar() {
		setBackground(Color.lightGray);
		addMouseMotionListener(new SplitterBarMouseMotionListener(this));
		addMouseListener(new SplitterBarMouseListener(this));
		}
	private void checkOtherComponents() {
		Rectangle currBounds = getBounds();  // get current position
		Component comps[]    = getParent().getComponents();
		Insets    insets     = getParent().getInsets();
		Rectangle parentBounds = getParent().getBounds();

		// determine which component "this" is
		int curr;
		for(curr=0; (curr < comps.length) && (comps[curr] != this); curr++);
		int origCurr = curr; // hold for part II check

		if (orientation == SplitterLayout.VERTICAL) {
			if (currBounds.y < originalBounds.y) { // moved up
				// could have moved _into_ splitter bars above (or top edge)
				//   and/or away from splitter bars below (or bottom edge)

				// check to see it we've bumped into a splitter above us.
				boolean done=false;
				for (int temp=curr-1; !done && temp > -1; temp--) {
					if (comps[temp] instanceof SplitterBar) {
						Rectangle r = comps[temp].getBounds();
						if (currBounds.y <= r.y + r.height) { // touching or above...
							comps[temp].setLocation(r.x, currBounds.y - r.height);
							// any comps in between should be hidden
							for(int c=curr-1; c > temp; c--)
								comps[c].setVisible(false);
							curr       = temp;
							currBounds = comps[temp].getBounds();
							} // touching or above
						else done=true; // no more compression
						} // it's a splitter bar
					} // for each component before us

				// did we push to far?
				if (currBounds.y <= insets.top) {
					int delta = currBounds.y - insets.top;
					// hide all components before that one
					for(int temp=curr-1; temp > -1; temp--)
						comps[temp].setVisible(false);
					// push all splitter bars into view
					done = false;
					for(int temp=curr;!done && temp <= origCurr; temp++)
						if (comps[temp] instanceof SplitterBar) {
							Point p = comps[temp].getLocation();
							p.y -= delta;
							comps[temp].setLocation(p);
							}
						else done = comps[temp].isVisible();
					} // pushed highest component off top edge

				// next, check if we exposed components below us
				curr = origCurr;
				// if the next component is not visible, show all between us & next
				//    splitter bar or bottom edge
				for(int temp=curr+1; temp<comps.length && !comps[temp].isVisible(); temp++)
					comps[temp].setVisible(true);
				} // VERTICAL -- moved up


			else if (currBounds.y > originalBounds.y) { // moved down
				// could have moved _into_ splitter bars below (or bottom edge)
				//   and/or away from splitter bars above (or top edge)

				// check to see it we've bumped into a splitter below us.
				boolean done=false;
				for (int temp=curr+1; !done && temp < comps.length; temp++) {
					if (comps[temp] instanceof SplitterBar) {
						Rectangle r = comps[temp].getBounds();
						if (currBounds.y + currBounds.height >= r.y) { // touching or below...
							comps[temp].setLocation(r.x, currBounds.y + currBounds.height);
							// any comps in between should be hidden
							for(int c=curr+1; c < temp; c++)
								comps[c].setVisible(false);
							curr       = temp;
							currBounds = comps[temp].getBounds();
							} // touching or above
						else done=true; // no more compression
						} // it's a splitter bar
					} // for each component before us

				// did we push to far?
				if ((currBounds.y + currBounds.height) >= (parentBounds.height-insets.bottom)) {
					int delta = currBounds.y + currBounds.height - (parentBounds.height-insets.bottom);
					// hide all components before that one
					for(int temp=curr+1; temp < comps.length; temp++)
						comps[temp].setVisible(false);
					// push all splitter bars into view
					done = false;
					for(int temp=curr;!done && temp >= origCurr; temp--)
						if (comps[temp] instanceof SplitterBar) {
							Point p = comps[temp].getLocation();
							p.y -= delta;
							comps[temp].setLocation(p);
							}
						else done = comps[temp].isVisible();
					} // pushed highest component off top edge

				// next, check if we exposed components below us
				curr = origCurr;
				// if the next component is not visible, show all between us & next
				//    splitter bar or bottom edge
				for(int temp=curr-1; temp>-1 && !comps[temp].isVisible(); temp--)
					comps[temp].setVisible(true);
				} // VERTICAL -- moved down
			} // orientation==VERTICAL

		else { // orientation == HORIZONTAL
			if (currBounds.x < originalBounds.x) { // moved left
				// could have moved _into_ splitter bars to left (or left edge)
				//   and/or away from splitter bars to right (or right edge)

				// check to see it we've bumped into a splitter above us.
				boolean done=false;
				for (int temp=curr-1; !done && temp > -1; temp--) {
					if (comps[temp] instanceof SplitterBar) {
						Rectangle r = comps[temp].getBounds();
						if (currBounds.x <= r.x + r.width) { // touching or above...
							comps[temp].setLocation(currBounds.x - r.width, r.y);
							// any comps in between should be hidden
							for(int c=curr-1; c > temp; c--)
								comps[c].setVisible(false);
							curr       = temp;
							currBounds = comps[temp].getBounds();
							} // touching or above
						else done=true; // no more compression
						} // it's a splitter bar