/*
1. Introduction
The main class to import is AWT (Abstract Windowing Toolkit)which is a set
of calasses allowing graphical interfaces. The class Graphics is a class of
AWT.
The supper class is Applet, java.applet is a package of the class Applet.
We imort then:
import java.awt.*;
import java.applet.*;
Graphics class Methods applied on an object:
if g is an object of the class Graphics, we have:
g.drawString(a string, x value, y value);
//Dispaly a string in a certain position
g.drawLine(xA,yA,xB,yB);
//Line between the point A(xA,yA) and the point B(xB,yB).
g.drawRect(xA,yA,xD,yD)
//Rectancle (A,B,C,D), with the first and the last points.
g.drawArc(xA,yA,withRectange. lengthRectangle, 0Angle, Angle);
//draw an arc
inside a rectangle
g.drawOval(xA,yA,xB,yB);
Two principal predefined methods:
void int() and void paint (Graphics g).
1. Initialization:
------------------
We initialize fonts, dimentions pictures ,...
Here we initialize fonts
public void init(){
The constructor Font of the class Font has
three parameters:
font-family, font-style, and font-size, we write:
setFont(new Font("font-familty", Font.STYLE , size));
We can have a combinaition of styles as:
Font.ITALIC + Font.BOLD
We use geleraly Font.ITALIC,Font.BOLD, and Font.PLAIN
}
2. Drawing
-----------
public void paint(Graphics g){
String Regards = "Regards";// seven characters
Position of each character of the string
int [][] Position {{xR,yR}, {xe,ye} , {xg,yg} ,
{xa,ya} , {xr,yr}, {xd,yd}, {xs,ys}};
Let's set color:
g.setColor(Color.green);
//Using drawString method, we can write:
for (int i = 0; i < Regards.length(); i++){
g.drawString(Regards.substring(i,i+1), Position[i][x],
Position[i][y]);
Whatever x and y. Example: x = 0 and y =1.
}
2. Applet program example
*/
import java.awt.*;
import java.applet.*;
public class Regards extends Applet {
static void Display(Graphics g, String text, int x, int y)
{
g.setFont(new Font("Bookman old style", Font.ITALIC+Font.BOLD,17));
g.setColor( Color.blue);
g.drawString(text,x,y);
}
public void paint (Graphics g){
String text1 =
"The file that contains the class Regards is named: Regards.java.";
String text2 =
"Compiled with : javac Regards.java, gives rise to : Regards.class.";
String text3 ="
It is not an application that runs with: java Regards, command line." ;
String text4 ="
But the browser shows Regards.class , that is the applet. " ;
Display(g, text1,100,100);
Display(g, text2,100,150);
Display(g, text3,100,200);
Display(g, text4,100,250);
}
}
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