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Thread: Java Applet Beginner

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    Default Java Applet Beginner

    This is my assignment from teacher:
    Copy and paste a SIMPLE method (that does not take input) from one of your other programs. The entire method should be pasted after the paint method, and called BY the paint method, passing the appropriate parameters. If the method displays output, you will need to pass the graphics object. Do not chooose a method that has multiple lines of output unless you really want a challenge.

    Is this a finished product? It says to call the method to the paint method, which I have done, is this a finished product?

    So this is my code:
    import java.applet.Applet;   // Imports the Applet class
    import java.awt.Graphics;    // Imports the Graphics class, used to draw lines, circles, squares, text, etc
     
    /** 
      * The HelloWorld class implements an applet that simply displays "Hello World!". 
      */ 
     
    // Our HelloWorld class extends  the Applet class, giving it access to all the methods of Applet.
    public class HelloWorld extends Applet {         
     
        // The paint method draws anything that is in our applet on the applet screen.  
        // It takes a graphics object (g), that is used to draw
     
        public void paint(Graphics g, double distance) 
        {     
     
            double x1;
            double x2;
            double y1;
            double y2;
            x1 = 1;
            x2 = 1;
            y1 = 1;
            y2= 1;
            g.drawString("Logan Carl Crone", 50, 25); 
            g.drawString("Can You Find Me??", 250,150);
     
     
            distance (x1, y1, x2, y2);
     
        }    
    public static double distance 
                   (double x1, double y1, double x2, double y2) { 
             double dx = x2 - x1;
             double dy = y2 - y1;
             double dsquared = dx*dx + dy*dy;
             double distance = Math.sqrt (dsquared);         
             return distance; 
     
    } 
    }


  2. #2
    Super Moderator curmudgeon's Avatar
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    Default Re: Java Applet Beginner

    Quote Originally Posted by LoganC View Post
    This is my assignment from teacher: ....

    Is this a finished product? It says to call the method to the paint method, which I have done, is this a finished product?
    Does it compile? Does it run? Does it do what you want it to do?

    One hint: your instructor told you to have the paint method call the other method -- you'll want to do something with the double value returned by distance, otherwise it's a futile method.

    Another hint: your instructor never told you to change the parameters of the paint method, something it looks like you've done. This may not be a wise thing to do.

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    Default Re: Java Applet Beginner

    How do I go about taking the return and printing it using drawString?

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    Default Re: Java Applet Beginner

    You get the double returned and put it into a double variable same as you normally would.

    double dbl = distance(x1, y1, x2, y2);

    Then use the dbl variable in drawString.

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    Default Re: Java Applet Beginner

    Thats where I am confused, how do i make it show up on the applet? g.drawString(dbl, 150,150); isnt working

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    Super Moderator curmudgeon's Avatar
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    Default Re: Java Applet Beginner

    Quote Originally Posted by LoganC View Post
    Thats where I am confused, how do i make it show up on the applet? g.drawString(dbl, 150,150); isnt working
    Ah, you need to translate it into a String. One "cheat" is to create a String on the spot by concatenating the numeric value with the empty String literal, "". i.e.,

       g. drawString("" + dbl, 150, 150);

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    Default Re: Java Applet Beginner

    Thanks a lot curmudgeon, was a great help.

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    Super Moderator curmudgeon's Avatar
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    Default Re: Java Applet Beginner

    You're welcome! Also note that there are other ways to change a number into a String, one being String.valueOf(dbl).

  9. The Following User Says Thank You to curmudgeon For This Useful Post:

    LoganC (October 8th, 2012)

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