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JCSplitterWindow and JCSeparator

Introduction · Sample Program Code · Orientation

JCSplitterWindow Size Characteristics · JCSeparator Size Characteristics

JCSeparator Orientation · Property Listing · Example Program

Introduction

A split window is a standard windows control that allows a user to adjust the boundary between two or more adjoining windows. The division between the window panes is called the split bar. JClass BWT's JCSplitterWindow is a container similar in function to Motif's XmPanedWindow, which manages one or more vertically or horizontally oriented children. The user can adjust the size of the panes by dragging the separator, which is controlled by a JCSeparator component that separates each pair of child windows. When creating JCSplitterWindow, the programmer does not have to add a JCSeparator, as it is added automatically. JCSeparator can be used within other BWT components. Both JCSplitterWindows and JCSeparator share a number of the same options, including the ability to set its orientation (either horizontal or vertical), and size.

There is no equivalent to JCSplitterWindow or JCSeparator in the Java Development Kit (JDK). JCSplitterWindow and JCSeparator conform to standard Windows 95 "look and feel" and behavior.

Behavior

• When a cursor passes over a JCSeparator, the cursor changes to a double-arrow.
• A user selecting a JCSeparator with the cursor can drag it across the area of either of the windows it divides. When the cursor is released, both contents of both windows are redrawn to fit to the new size.

Keyboard Traversal

There are no keyboard traversal routines that apply to JCSplitterWindow or JCSeparator.

Sample Program Code

The following lengthy code example shows how a JCSplitterWindow can incorporate a JCMultiColumnList and a JCOutliner. All that needs to be done is to create a window and then add components to it.

package jclass.bwt.examples;
import jclass.bwt.BWTEnum;
import jclass.bwt.JCItemEvent;
import jclass.bwt.JCMultiColumnList;
import jclass.bwt.JCOutliner;
import jclass.bwt.JCOutlinerEvent;
import jclass.bwt.JCOutlinerFolderNode;
import jclass.bwt.JCOutlinerListener;
import jclass.bwt.JCOutlinerNode;
import jclass.bwt.JCOutlinerNodeStyle;
import jclass.bwt.JCSplitterWindow;
import jclass.contrib.ContribFrame;
import jclass.util.JCUtilConverter;
import jclass.util.JCVector;
import java.awt.*;

/**
 * This example demonstrates a several components in a JCSplitterWindow.
 */
public class splitterWindow extends java.applet.Applet
implements JCOutlinerListener {

final static String[] column_labels = {
	"Name", "Title", "Address", "Phone", "Salary"
};
final static String dept[] = { "Management", "Accounting", "R&D" };

final static String mgmt_items[] = {
"John Kricfalusi|President|983 Nickelodeon Street, Rexdale Ontario|(414) 999-9876|$10,000",
"Hikaru Takei|VP|134 Adelaide Street, Suite 204, Toronto Ontario|(416) 594-1026|$23K",
"James Q. Doohan|Director|1701 Planetia Blvd., Anytown, U.S.A.||$245,000"
};

final static String accounting_items[] = {
"Hikaru I. Takei|Payroll|134 Adelaide Street E., Suite 204, Anytown, U.S.A.|(999) 594-1026",
"Melissa A. Truman|Receivable|475 Woodview Line, Anytown, U.S.A.|(999) 555-9030|$50,250",
"Stephanie L. Truman|Payroll|388 Appleby Road, Anytown, U.S.A.|(999) 555-2642|$85,750"
};

final static String rd_items[] = {
"James Q. Doohan|Engineer|1701 Planetia Blvd., Anytown, U.S.A.||$245,000",
"John F. Kricfalusi|Physicist|983 Nickelodeon Street, Anytown, U.S.A.|(999) 555-9876|$10,000",
"Marc Lenard|Engineer|6 Gene Crescent, Anytown, U.S.A.|(999) 555-1212|$10/hr.",
"Hikaru I. Takei|Musician|134 Adelaide Street E., Suite 204, Anytown, U.S.A.|(999) 594-1026|50%",
"Melissa A. Truman|QA|475 Woodview Line, Anytown, U.S.A.|(999) 555-9030|$50,250",
"Stephanie L. Truman|Technical Writer|388 Appleby Road, Anytown, U.S.A.|(999) 555-2642|$85,750",
"Bill West|System Analyst|1001 Spumco Way, Anytown, U.S.A.|(999) 555-9966|$17,500"
};

final static String[][] item_data = { mgmt_items, accounting_items, rd_items };

JCMultiColumnList list;

/**
 * JCOutlinerListener methods
 */

/*
 * Writes a folder's items to the list when it is selected
 * It simulates the reading of the data from a database.
 */
public void itemStateChanged(JCItemEvent item_ev) {
	JCOutlinerEvent ev = (JCOutlinerEvent) item_ev;
	JCOutlinerFolderNode folder = (JCOutlinerFolderNode) ev.getNode();
	JCOutliner outliner = (JCOutliner) ev.getSource();

	// Ignore root node
	if (folder == outliner.getRootNode()) {
		list.clear();
		return;
	}

	// Add children to list
	if (ev.getStateChange() == JCItemEvent.SELECTED) {
		list.setBatched(true);
		list.clear();
		int pos = ((Integer)folder.getUserData()).intValue();
		String[] items = item_data[pos];
		for (int i=0; i < items.length; i++) {
			JCVector label = outliner.getConverter()
				.toVector(this, items[i], '|', false);
			list.addItem(label);
		}
		list.setBatched(false);
	}
}

public void outlinerFolderStateChangeBegin(JCOutlinerEvent ev) {}
public void outlinerFolderStateChangeEnd(JCOutlinerEvent ev) {}
public void outlinerNodeSelectBegin(JCOutlinerEvent ev) {}
public void outlinerNodeSelectEnd(JCOutlinerEvent ev) {}

public void init() {
	Image folder_closed = JCUtilConverter.toImage(this, "../images/folderc.gif");
	Image top = JCUtilConverter.toImage(this, "../images/top.gif");


	// Force contents to be the same size as the applet
	setLayout(new GridLayout(1,1));
	setBackground(Color.lightGray);

	JCOutlinerNodeStyle style = new JCOutlinerNodeStyle();
	style.setFolderOpenIcon(top);
	style.setFolderClosedIcon(top);

	JCOutlinerFolderNode root = new JCOutlinerFolderNode(null, "Personnel");
	root.setStyle(style);

	JCOutlinerNodeStyle folder_style = new JCOutlinerNodeStyle();
	folder_style.setFolderClosedIcon(folder_closed);
	folder_style.setFolderOpenIcon(folder_closed);

	JCOutlinerFolderNode f = null;
	for (int i=0; i < dept.length; i++) {
		f = new JCOutlinerFolderNode(null, BWTEnum.FOLDER_CLOSED, dept[i]);
		f.setUserData(new Integer(i));
		f.setStyle(folder_style);
		root.addNode(f);
	}

	JCOutliner outliner = new JCOutliner(root);
	outliner.getOutliner().setBackground(Color.white);
	outliner.setPreferredSize(150, 300);
	outliner.addItemListener(this);

	list = new JCMultiColumnList();
	list.getList().setBackground(Color.white);
	list.setColumnLabels(column_labels);
	list.setPreferredSize(500, 300);

	// Open last folder
	outliner.selectNode(f, null);
	outliner.setNodeState(f, BWTEnum.FOLDER_OPEN_ALL, true);

	JCSplitterWindow window = new JCSplitterWindow(BWTEnum.HORIZONTAL);
	window.add(outliner);
	window.add(list);

	add(window);
}

public static void main(String args[]) {
	ContribFrame frame = new ContribFrame("SplitterWindow");
	splitterWindow s = new splitterWindow();

	s.init();
	frame.add(s);
	frame.pack();
	frame.show();
}
}

Even though the code does not specifically add a JCSeparator statement, it is invoked automatically by the JCSplitterWindow in the program.

Note how in the illustration the cursor is positioned over the JCSeparator, and how it changes to a double-arrow state to indicate the presence of a JCSplitterWindow.

This sample code is incorporated into the example file splitterWindow.class provided with JClass BWT. For information on how to run this program, see the " Example Program" section at the end of this chapter.

Orientation

By default, the JCSplitterWindow constructor creates an empty vertical window. To set the orientation of the JCSeparator that divides the windows, use HORIZONTAL or VERTICAL, as shown in the following code fragment:

JCSplitterWindow window = new JCSplitterWindow(VERTICAL);
        window.add(outliner);
        window.add(list);
        add(window);

JCSplitterWindow Size Characteristics

Typically, JCSplitterWindows are sized to match the height or width of the component it controls. By default, the preferredHeight and the preferredWidth methods return the sum of all children's preferred width if orientation is horizontal; otherwise it returns the maximum preferred width of all children.

In programs where the it is desirable to set a limit on the extent to which a user can resize a window, use the MinChildSize method, which set a minimum size (in pixels) to which a child can be resized by the user (default: 20).

JCSeparator Size Characteristics

Though it is most often in conjunction with JCSplitterWindow, JCSeparator can be used within other components. When used separately from JCSplitterWindow, it can be directly manipulated by the program.

Both preferredHeight and preferredWidth returns the shadow thickness value if it is a horizontal or vertical separator respectively; otherwise it returns a value of 100.

JCSeparator Orientation

Normarly the JCSeparator orientation is set by the JCSeparator constructor. By default, a horizontal orientation is created unless specified otherwise.

The current orientation of a JCSeparator can also be set or read using the Orientation method. Orientation takes one of two parameters: HORIZONTAL or VERTICAL.

Property Listing

The following summarizes the properties of JCSplitterWindow and JCSeparator. Complete reference documentation is available online in standard javadoc format in jclass.bwt.JCSplitterWindow.html and jclass.bwt.JCSeparator.html.

Example Program

Demonstration programs and example code containing JCSplitterWindow come with JClass BWT. The examples can be viewed in applet form by launching index.html within the /jclass/bwt/examples directory. splitterWindow.class can also be run as a stand-alone Java application from the command prompt by typing:

     java jclass.bwt.examples.splitterWindow