Program 1
| | ColorPresenter.java - Det samlede farveblander program (kun view og kontrol klasser). | Lecture 12 - slide 15 : 30 Program 1 |
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
/** Color class extended with internet color encoding operation
which is redefined via toString() */
class INColor extends Color {
public INColor(int red, int green, int blue) {
super(red,green,blue);
}
private String twoCharColor(int colorNumber){
/* Convert the parameter, a color, to a hexadecimal number of length exactly two */
if (colorNumber >= 0 && colorNumber < 16) return "0" + Integer.toHexString(colorNumber);
else if (colorNumber >= 16 && colorNumber < 256) return Integer.toHexString(colorNumber);
else return "??";
}
public String toString () {
/** Return the seven character long internet color encoding of this color */
return "#" + twoCharColor(getRed()) + twoCharColor(getGreen()) + twoCharColor(getBlue());
}
}
class ColorPanel extends Panel {
public ColorPanel (Label lab, TextField text,
Scrollbar slider, ColorListener listener){
GridBagConstraints c = new GridBagConstraints();
GridBagLayout gridbag = new GridBagLayout();
setLayout(gridbag);
c.fill = GridBagConstraints.HORIZONTAL;
add(lab);
c.gridwidth = GridBagConstraints.REMAINDER;
gridbag.setConstraints(text, c);
add(text);
c.weightx = 1.0;
c.gridwidth = 1;
gridbag.setConstraints(slider, c);
slider.setMaximum(255);
slider.setBlockIncrement(10);
slider.setUnitIncrement(1);
add(slider);
text.addActionListener (listener);
slider.addAdjustmentListener (listener);
}
} // end class ColorPanel
public class ColorPresenter extends Applet {
public static final int Red = 0;
public static final int Green = 1;
public static final int Blue = 2;
/** Read the color from a text field specified by the parameter */
public int readColor (int COLOR) {
String str;
if (COLOR == Red) str = redTextField.getText();
else if (COLOR == Green) str = greenTextField.getText();
else if (COLOR == Blue) str = blueTextField.getText();
else str = "";
return Integer.parseInt(str);
}
/** Write the color to a text field as specified by the parameters */
public void writeColor (int COLOR, int val){
if (COLOR == Red) redTextField.setText(Integer.toString(val,10));
else if (COLOR == Green) greenTextField.setText(Integer.toString(val,10));
else if (COLOR == Blue) blueTextField.setText(Integer.toString(val,10));
}
/** Construct individual components */
private Label title = new Label ("Color adjuster", Label.CENTER);
private Label redLabel = new Label ("Red:");
private TextField redTextField = new TextField ("0",5);
private Scrollbar redSlider = new Scrollbar(Scrollbar.HORIZONTAL,0,1,0,255);
private Label greenLabel = new Label ("Green:");
private TextField greenTextField = new TextField ("0",5);
private Scrollbar greenSlider = new Scrollbar(Scrollbar.HORIZONTAL,0,1,0,255);
private Label blueLabel = new Label ("Blue:");
private TextField blueTextField = new TextField ("0",5);
private Scrollbar blueSlider = new Scrollbar(Scrollbar.HORIZONTAL,0,1,0,255);
private Label hexTextField = new Label ("#000000");
private ColorBlop colorBlop = new ColorBlop(Color.white);
private ColorListener listener = new ColorListener (this);
private ColorPanel redGroup =
new ColorPanel(redLabel, redTextField, redSlider, listener);
private ColorPanel greenGroup =
new ColorPanel(greenLabel, greenTextField, greenSlider, listener);
private ColorPanel blueGroup =
new ColorPanel(blueLabel, blueTextField, blueSlider, listener);
/** Applet init */
public void init() {
setLayout(new GridLayout(6,1));
add(title);
add(redGroup); add(greenGroup); add(blueGroup);
add(colorBlop);
add(hexTextField);
resize (400,250);
adjust();
} //end init
private boolean inColorRange (int c){
return c >= 0 && c <= 255;
}
/* Given the scrollbar sl has changed it's value to val,
adjust the user interface*/
public void sliderAdjust (Scrollbar sl, int val){
if (sl == redSlider) writeColor(Red, val);
else if (sl == greenSlider) writeColor(Green, val);
else if (sl == blueSlider) writeColor(Blue, val);
adjust();
}
/* Given that a text field has been changed,
adjust the user interface */
public void adjust() {
Color newColor;
int r,g,b;
r = readColor(Red); g = readColor(Green); b = readColor(Blue);
if (inColorRange(r) && inColorRange(g) && inColorRange(b)){
newColor = new INColor(readColor(Red), readColor(Green), readColor(Blue));
colorBlop.setColor(newColor);
colorBlop.repaint();
hexTextField.setText(newColor.toString());
// adjust scrollbars:
redSlider.setValue(r); greenSlider.setValue(g); blueSlider.setValue(b);
} else hexTextField.setText("ERROR");
}
/* Draws a box around this panel. */
public void paint(Graphics g) {
Dimension d = getSize();
g.drawRect(0,0, d.width - 3, d.height - 3);
}
/* Puts a little space between the panel and its contents */
public Insets getInsets() {
return new Insets(10,10,10,10);
}
public static void main(String[] args){
Frame f = new Frame("Color adjuster");
f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
} );
ColorPresenter adjuster = new ColorPresenter();
adjuster.init();
f.add("Center", adjuster);
f.pack();
f.setVisible(true);
} // end main
}
class ColorListener implements ActionListener, AdjustmentListener {
// Listens to events from components of a ColorPresenter
private ColorPresenter presentation;
private INColor currentColor;
public ColorListener (ColorPresenter presentation){
this.presentation = presentation;
}
public void actionPerformed(ActionEvent action){
presentation.adjust();
}
public void adjustmentValueChanged (AdjustmentEvent adjustment){
presentation.sliderAdjust((Scrollbar)adjustment.getAdjustable(),
adjustment.getValue());
}
} // end class ColorListener
class ColorBlop extends Canvas {
private Dimension size = new Dimension(100,100);
private Color currentColorOfBlop;
ColorBlop(Color c){
currentColorOfBlop = c;
}
public void setColor (Color c){
currentColorOfBlop = c;
}
public void paint (Graphics page) {
page.setColor(currentColorOfBlop);
page.fillRect(0,0,400,200);
}
public Dimension getMinimumSize() {
return size;
}
public Dimension getPreferredSize() {
return getMinimumSize();
}
} // end class ColorBlop
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