All about Nick Harms

JavaScript troubles

Hopefully all that information helps. There is not a specific image with that name as you asked before, the function selects the image depending on the time. I am pretty sure thats how it works.

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

it screwed up my code again

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

Bear Bibeault wrote:OK, that looks a little better.

Is there really an image file with the resulting name in the same folder as the HTML file?

By the way, using a tool like Firebug in Firefox will let you look at the active HTML DOM so you can see what the result of your statement actually becomes in the DOM.

Chrome also has such tools.

well the mapNum variable is referencing the getMap() function,
My book says The getMap() function which returns a number from 0 to 23. The number matches the number of the sky map image to show based on the current date and time. That function has been placed in an external javascript file named datetime.js which you can see I accessed in the top of the code.
The timeStr also refers to a function in that file and it actually works. In the project folder there are 0-23 images and I guess the function reads the time and displays the apropriate picture.

My task was this
4. Scroll down the file to the div element with the id value maps and replace the line
(which is now gone) with a script element that writes the following html code.

where mapNum is the value of the mapNum variable

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

Bear Bibeault wrote:When posting HTML be sure to click the 'disable HTML' checkbox.

First, you need to fix your syntax. Your quoting is wrong.

Second, if the image tag doesn't have a src attribute to identify its image file, of course nothing will appear.

Well here is what I have now
If the quoting is still wrong that's what I need help on, and what that last part posted isn't what I wanted to post anyways, it did have a src
Can you help me from this further? It is still not showing an image.

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

Bear Bibeault wrote:You haven't done a particularly god job of letting us know what problem you are having.

# <script type="text/javascript">
# document.write('<img id="sky" ' />');
# </script>

That's what I have so far, I don't know how to explain it any better, I copied the question out of the book, did my best to try it for myself and the image is not displaying.
I need help to figure out what is wrong with my script and why it is not doing what the book wants it to do.

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

I just wish someone could help me.......

14 years ago

HTML Pages with CSS and JavaScript

JavaScript troubles

Ok , the problem is

Scroll down to the div element with id value maps and replace the line
<img id="sky" src="sky0.jpg" alt="" />
with a script element that writes the following html code:
<img id='sky' src='mapNum.jpg' alt=' ' />
were mapNum is the value of the mapNum Variable.

I've been redoing this several times and can't seem to get everywhere,
I had to do a similar thing with the clock but got it to work right away.

Any help is greatly appreciated!

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>

<title>SkyWeb: The Planisphere</title>
<link href="skyweb.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="datetime.js"></script>
<script type="text/javascript">
/*
timeStr is a text string containing the current date and time
mapNum is the number of the map to display in the planisphere
*/
var timeStr=showDateTime();
var mapNum=getMap();
</script>
</head>
<body>
<div id="pageContent">
<div id="logo">
<img src="skyweb.jpg" alt="SkyWeb" />
</div>
<div id="maps">
<script type="text/javascript">
document.write('<img id="sky" src="sky' + getMap() + '.jpg" alt="sky map"' />');
</script>
<img id="mask" src="mask.gif" alt="" />
<div id="datetime">
<script type="text/javascript">
document.write(timeStr);
</script>
</div>
</div>
<div id="content">
<h1>The Planisphere</h1>
<p>A <b>planisphere</b> is a visual aid to astronomers and stargazers.
It consists of two disks: one displays all of the visible
constellations in the night sky, and the other covers the first
and contains a window that indicates the portion of the sky currently
visible. The second disk is then rotated to match the current date and
time. Planispheres come in a variety of sizes and types. The important
thing to remember is that you must have a planisphere that matches
the longitude of your stargazing location.</p>
<p>On the right is an online planisphere. It consists of two images. The
bottom image contains the sky map; the top image contains the viewing
window. Rather than turning the viewing window, this planisphere is
automatically rotated for you, displaying the current date and time
and visible constellations for observers at a longitude of
40<sup>°</sup> North. To update the planisphere you can click
the <span class="button">Refresh</span> or
<span class="button">Reload</span> button on your browser. The planisphere
will change, representing the nighttime sky to the nearest hour.</p>
</div>
<div id="links">
| <a href="#">Home Page</a>
| <a href="#">The Night Sky</a>
| <a href="#">The Moon</a>
| <a href="#">The Planets</a>
| <a href="#">The Messier Objects</a>
| <a href="#">Stars</a> |
</div>
</div>
</body>
</html>

14 years ago

HTML Pages with CSS and JavaScript

Return type required

Never mind I got it, should be RetailItem one= new RetailItem();

15 years ago

Beginning Java

Return type required

Ok now its saying cannot find symbol - class item in the demo. on the item one = new RetailItem(); line. Why is that? It matches the class name.

/**
Demo Program for the Retail Item class
Chapter 6, Programming Challenge 4
*/
public class RetailItemDemo
{
public static void main(String[] args)
{
//Create the objects
Item one = new RetailItem();
Item two = new RetailItem();
Item three = new RetailItem();
// Set item one info.
one.setDescription("Jacket");
one.setUnitsOnHand(12);
one.setPrice(59.95);
// Set item two info.
two.setDescription("Designer Jeans");
two.setUnitsOnHand(40);
two.setPrice(34.95);
// Set item three info.
three.setDescription("Shirt");
three.setUnitsOnHand(20);
three.setPrice(24.95);
//Display object 1 info
System.out.println(" Item 1 Information" );
System.out.println("====================================");
System.out.println("Description: " + one.getdescription());
System.out.println("Units on hand: " + one.UnitsOnHand());
System.out.println("Price: " + one.Price);
//Display object 2 info
System.out.println(" Item 2 Information" );
System.out.println("====================================");
System.out.println("Description: " + two.getdescription());
System.out.println("Units on hand: " + two.UnitsOnHand());
System.out.println("Price: " + two.Price);
//Display object 3 info
System.out.println(" Item 3 Information" );
System.out.println("====================================");
System.out.println("Description: " + three.getdescription());
System.out.println("Units on hand: " + three.UnitsOnHand());
System.out.println("Price: " + three.Price);
}
}

15 years ago

Beginning Java

Return type required

This public Retailitem() is giving me this error, not sure why, to the naked eye it looks just like my example, probably a simple fixed.
Says invalid method declaration return type required,
This is a class a demo uses.

/**
RetailItem Class
*/
public class RetailItem
{
private String Description;
private int UnitsOnHand;
private double Price;
public Retailitem()
{
Description = "";
UnitsOnHand = 0;
Price = 0;
}
public Retailitem(String myDescription, int myUnitsOnHand, double myPrice)
{
Description = myDescription
UnitsOnHand = myUnitsOnHand
Price = myPrice
/**
The setDescription method sets the description.
@param myDescription The description.
*/
public void setDescription(String myDescription)
{
Description = myDescription;
}
/**
The setUnitsOnHand method returns the Units on hand.
@param myUnitsOnHand The units on hand.
*/
public void setUnitsOnHand(myUnitsOnHand)
{
UnitsOnHand = myUnitsOnHand;
}
/**
The setUnitsOnHand method returns the Units on hand.
@param myUnitsOnHand The units on hand.
*/
public void setPrice(myPrice)
{
Price = myPrice;
}
/**
The getdescription method returns a description.
@return The description.
*/
public String getDescription()
{
return Description;
}
/**
The getUnitsOnHand method returns Units on Hand.
@return the units on hand.
*/
public double getUnitsOnHand()
{
return UnitsOnHand;
}
/**
The getPrice method returns the Price.
@return price.
*/
public double getPrice()
{
return Price;
}
}

15 years ago

Beginning Java

Programing challenge

Well I know you could say double rad were it reads the input but how would you initialize it to 0 there?
Figured I might as well ask while Im here.

15 years ago

Beginning Java

Programing challenge

YAY!
Thanks again, you are my hero. I knew it was something stupid!
Another AH HA! moment thanks to java ranch.

15 years ago

Beginning Java

Programing challenge

I thought that was what the object did? Do i simply need to move the object to after I ask them instead of before.

15 years ago

Beginning Java

Programing challenge

There ya go!
I know this is probably a dumb question but i want to be sure that I dont need to change anything in the class after switching these right?

15 years ago

Beginning Java

Programing challenge

Well, the demo demonstrates the class by using its methods, It will first ask the user for their radius and then send that to the class to be used in the methods to find the information. the methods return the desired information which you call by calling the object reference and the method name, such as circle.getDiameter.

15 years ago

Beginning Java

Nick Harms

Recent posts by Nick Harms