Ich bereite mich für meine Java Prüfung vor
. Eine beliebte Prüfungsfrage war ein Bild im Hintergrund anzeigen und ein Diagramm im Vordergrund erstellen. Folgende Einschränkungen gelten: Nur AWT darf verwendet werden - kein Swing oder FX und keine Drittanbieter-Bibliotheken (Standard-API Java 1.6 vermutlich).Ich habe es nicht geschafft das Bild als ein Hintergrundbild zu machen, sodass die Diagramme auf dem Hintergrundbild liegen und sichtbar bleiben. Aktuell habe ich das Bild als ein Header-Bild gemacht. Ich habe ein Screenshot von meiner Anwendung gemacht.
Und hier ist mein Code:
Code: Alles auswählen
public class Main {
public static void main(String[] args) {
MainWindow mainWindow = new MainWindow();
}
}Code: Alles auswählen
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Panel;
import java.awt.Toolkit;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
public class MainWindow extends Frame{
public MainWindow() {
setIconImage(Toolkit.getDefaultToolkit().getImage("/home/user/Bilder/MaverickEyes_Favicon_Image.gif"));
setTitle("Bild und Diagramme");
setSize(800, 600);
double[] values = new double[3];
String[] names = new String[3];
values[0] = 1;
names[0] = "Item 1";
values[1] = 2;
names[1] = "Item 2";
values[2] = 4;
names[2] = "Item 3";
setLayout(new GridLayout(2,1));
Panel top = new Panel(new FlowLayout());
top.add(new ImageComponent("/home/user/Bilder/dreamweaver-800x600.jpg"));
Panel content = new Panel(new GridLayout(1,2));
content.setBackground(Color.WHITE);
BarChart barChart = new BarChart(values, names, "Bar Chart");
barChart.setBackground(Color.WHITE);
content.add(barChart);
PieChart pieChart = new PieChart();
pieChart.setBackground(Color.WHITE);
content.add(pieChart);
add(top);
add(content);
WindowListener wndCloser = new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
};
addWindowListener(wndCloser);
setVisible(true);
}
}Code: Alles auswählen
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Panel;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
class ImageComponent extends Panel {
BufferedImage img;
public void paint(Graphics g) {
g.drawImage(img, 0, 0, null);
}
public ImageComponent(String path) {
try {
img = ImageIO.read(new File(path));
} catch (IOException e) {
e.printStackTrace();
}
}
public Dimension getPreferredSize() {
if (img == null) {
return new Dimension(200,200);
} else {
return new Dimension(img.getWidth(), img.getHeight());
}
}
}Code: Alles auswählen
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Panel;
public class BarChart extends Panel {
private double[] values;
private String[] names;
private String title;
public BarChart(double[] v, String[] n, String t) {
names = n;
values = v;
title = t;
}
public void paint(Graphics g) {
super.paint(g);
if (values == null || values.length == 0)
return;
double minValue = 0;
double maxValue = 0;
for (int i = 0; i < values.length; i++) {
if (minValue > values[i])
minValue = values[i];
if (maxValue < values[i])
maxValue = values[i];
}
Dimension d = new Dimension(200,200);
int clientWidth = d.width;
int clientHeight = d.height;
int barWidth = clientWidth / values.length;
Font titleFont = new Font("SansSerif", Font.BOLD, 20);
FontMetrics titleFontMetrics = g.getFontMetrics(titleFont);
Font labelFont = new Font("SansSerif", Font.PLAIN, 10);
FontMetrics labelFontMetrics = g.getFontMetrics(labelFont);
int titleWidth = titleFontMetrics.stringWidth(title);
int y = titleFontMetrics.getAscent();
int x = (clientWidth - titleWidth) / 2;
g.setFont(titleFont);
g.drawString(title, x, y);
int top = titleFontMetrics.getHeight();
int bottom = labelFontMetrics.getHeight();
if (maxValue == minValue)
return;
double scale = (clientHeight - top - bottom) / (maxValue - minValue);
y = clientHeight - labelFontMetrics.getDescent();
g.setFont(labelFont);
for (int i = 0; i < values.length; i++) {
int valueX = i * barWidth + 1;
int valueY = top;
int height = (int) (values[i] * scale);
if (values[i] >= 0)
valueY += (int) ((maxValue - values[i]) * scale);
else {
valueY += (int) (maxValue * scale);
height = -height;
}
g.setColor(Color.red);
g.fillRect(valueX, valueY, barWidth - 2, height);
g.setColor(Color.black);
g.drawRect(valueX, valueY, barWidth - 2, height);
int labelWidth = labelFontMetrics.stringWidth(names[i]);
x = i * barWidth + (barWidth - labelWidth) / 2;
g.drawString(names[i], x, y);
}
}
}Code: Alles auswählen
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Panel;
import java.awt.Rectangle;
class Slice {
double value;
Color color;
public Slice(double value, Color color) {
this.value = value;
this.color = color;
}
}
class PieChart extends Panel {
Slice[] slices = { new Slice(5, Color.black), new Slice(33, Color.green),
new Slice(20, Color.yellow), new Slice(15, Color.red) };
PieChart() {
}
public void paint(Graphics g) {
drawPie((Graphics2D) g, getBounds(), slices);
}
void drawPie(Graphics2D g, Rectangle area, Slice[] slices) {
area = new Rectangle(10, 10, 200, 200);
double total = 0.0D;
for (int i = 0; i < slices.length; i++) {
total += slices[i].value;
}
double curValue = 0.0D;
int startAngle = 0;
for (int i = 0; i < slices.length; i++) {
startAngle = (int) (curValue * 360 / total);
int arcAngle = (int) (slices[i].value * 360 / total);
g.setColor(slices[i].color);
g.fillArc(area.x, area.y, area.width, area.height, startAngle, arcAngle);
curValue += slices[i].value;
}
}
}Danke!!!
