MassBot1: Created page with "/** * GeometryApplet00: Demonstrating GUI + Event Handling in Swing / import javax.swing.; import javax.swing.b..."

2013-11-07T19:36:02Z

Created page with "<syntaxhighlight lang="java" line start="1" enclose="div">* * GeometryApplet00: Demonstrating GUI + Event Handling in Swing: import javax.swing.*; import javax.swing.b..."

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<syntaxhighlight lang="java" line start="1" enclose="div">/**
* GeometryApplet00: Demonstrating GUI + Event Handling in Swing
*/

import javax.swing.*;
import javax.swing.border.*;

import java.awt.*;
import java.awt.event.*;

import java.applet.*;

interface IGeometryConstants {
int SQUARE = 0;
int CIRCLE = 1;
int ELLIPSE = 2;
String[] shapeNames = {"Square", "Circle", "Ellipse"};

int SMALL = 0;
int MEDIUM = 1;
int LARGE = 2;
String[] sizeNames = {"Small", "Medium", "Large"};
}

public class GeometryApplet00 extends JApplet
implements IGeometryConstants {

// Panel for shape
JPanel shapePanel;
ButtonGroup shapeGroup;
JRadioButton squareRB;
JRadioButton circleRB;
JRadioButton ellipseRB;

// Panel for x, y coordinates
JPanel xyPanel;
JLabel xLabel;
JTextField xInput;
JLabel yLabel;
JTextField yInput;

// Panel for size and fill
JPanel sizePanel;
JLabel sizeLabel;
JComboBox sizeChoices;
JCheckBox fillCB;

// Box for shape, coordinates, size and fill
Box leftBox;

// Panel for draw button, drawing region and message display.
JPanel rightPanel;
JButton drawButton;
JScrollPane scrollPane;
DrawRegion drawRegion;
JTextField messageDisplay;

// Top container
Container topContainer;

public void init() {
makeShapePanel();
makeXYPanel();
makeSizePanel();
makeLeftBox();
makeRightPanel();

addListeners();

topContainer = getContentPane();
topContainer.add(leftBox, BorderLayout.WEST);
topContainer.add(rightPanel, BorderLayout.CENTER);

try {
UIManager.setLookAndFeel(
UIManager.getSystemLookAndFeelClassName()
// "com.sun.java.swing.plaf.motif.MotifLookAndFeel"
// "com.sun.java.swing.plaf.windows.WindowsLookAndFeel"
// "javax.swing.plaf.mac.MacLookAndFeel"
);
}
catch(Exception e) {
messageDisplay.setText(e.toString());
}
SwingUtilities.updateComponentTreeUI(this);
}

// Panel for shape
void makeShapePanel() {
squareRB = new JRadioButton(shapeNames[SQUARE], true);
circleRB = new JRadioButton(shapeNames[CIRCLE], false);
ellipseRB = new JRadioButton(shapeNames[ELLIPSE], false);

shapeGroup = new ButtonGroup();
shapeGroup.add(squareRB);
shapeGroup.add(circleRB);
shapeGroup.add(ellipseRB);

shapePanel = new JPanel();
shapePanel.setLayout(new FlowLayout());
shapePanel.add(squareRB);
shapePanel.add(circleRB);
shapePanel.add(ellipseRB);
shapePanel.setBorder(new TitledBorder("Shapes"));
}

// Panel for x,y coordinates
void makeXYPanel() {
xyPanel = new JPanel();

xLabel = new JLabel("X Coordinate:");
yLabel = new JLabel("Y Coordinate:");

xInput = new JTextField(5);
yInput = new JTextField(5);

xyPanel.setLayout(new GridLayout(2,2));
xyPanel.add(xLabel);
xyPanel.add(xInput);
xyPanel.add(yLabel);
xyPanel.add(yInput);
}

// Panel for size and fill
void makeSizePanel() {
sizePanel = new JPanel();

sizeLabel = new JLabel("Size:");

sizeChoices = new JComboBox(sizeNames);
sizeChoices.setSelectedIndex(0);

fillCB = new JCheckBox("Fill", false);

sizePanel.setLayout(new FlowLayout());
sizePanel.add(sizeLabel);
sizePanel.add(sizeChoices);
sizePanel.add(fillCB);
}

// Box for shape, coordinates, size and fill
void makeLeftBox() {
leftBox = new Box(BoxLayout.Y_AXIS);

leftBox.add(shapePanel);
leftBox.add(Box.createGlue());
leftBox.add(xyPanel);
leftBox.add(Box.createGlue());
leftBox.add(sizePanel);
}

// Panel for message display, draw button, and drawing region
void makeRightPanel() {
rightPanel = new JPanel();

messageDisplay = new JTextField("MESSAGE DISPLAY");
messageDisplay.setEditable(false);

drawButton = new JButton("Draw");

drawRegion = new DrawRegion();
scrollPane = new JScrollPane(drawRegion);

rightPanel.setLayout(new BorderLayout());
rightPanel.add(drawButton, BorderLayout.NORTH);
rightPanel.add(messageDisplay, BorderLayout.SOUTH);
rightPanel.add(scrollPane, BorderLayout.CENTER);
}

// Add the listeners.
void addListeners() {
drawButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
int shape,
xCoord,
yCoord,
width;

messageDisplay.setText("");
// Get the shape
if(squareRB.isSelected())
shape = SQUARE;
else if(circleRB.isSelected())
shape = CIRCLE;
else if(ellipseRB.isSelected())
shape = ELLIPSE;
else {
messageDisplay.setText("Unknown shape.");
return;
}

// Get the coordinates
try {
xCoord = Integer.parseInt(xInput.getText());
yCoord = Integer.parseInt(yInput.getText());
} catch (NumberFormatException e) {
messageDisplay.setText("Illegal coordinates.");
return;
}

// Get the size
switch(sizeChoices.getSelectedIndex()) {
case SMALL : width = 30;
break;
case MEDIUM : width = 60;
break;
case LARGE : width = 120;
break;
default : messageDisplay.setText("Unknown size.");
return;
}

messageDisplay.setText("Drawing " + shapeNames[shape]);

drawRegion.doDraw(shape,
xCoord,
yCoord,
fillCB.isSelected(),
width);
}
});
}
}

class DrawRegion extends JPanel
implements IGeometryConstants {
// Values needed for drawing the shape
private int shape;
private int xCoord;
private int yCoord;
private boolean fillFlag;
private int width;

// Default constructor
public DrawRegion() {
setSize(300,300);
setBackground(Color.white);
}

// Overridden to always keep the same size
public Dimension getPreferredSize() {
return getSize();
}

// Set the values and repaint the drawing region.
public void doDraw(int shape,
int xCoord, int yCoord,
boolean fillFlag, int width) {

this.shape = shape;
this.xCoord = xCoord;
this.yCoord = yCoord;
this.fillFlag = fillFlag;
this.width = width;

repaint();
}

// Do the drawing of the shape
public void paintComponent (Graphics g) {
super.paintComponent(g);
switch (shape) {
case SQUARE:
if (fillFlag) g.fillRect(xCoord, yCoord, width, width);
else g.drawRect(xCoord, yCoord, width, width);
break;
case CIRCLE:
if (fillFlag) g.fillOval(xCoord, yCoord, width, width);
else g.drawOval(xCoord, yCoord, width, width);
break;
case ELLIPSE:
if (fillFlag) g.fillOval(xCoord, yCoord, width, width/2);
else g.drawOval(xCoord, yCoord, width, width/2);
break;
}
}

}
</syntaxhighlight>

Yurttas/PL/OOL/Java/F/05/01/05/10/GeometryApplet00.java - Revision history

MassBot1: Created page with "/** * GeometryApplet00: Demonstrating GUI + Event Handling in Swing */ import javax.swing.*; import javax.swing.b..."

MassBot1: Created page with "/** * GeometryApplet00: Demonstrating GUI + Event Handling in Swing / import javax.swing.; import javax.swing.b..."