THE JAVA APPLETS ANY SERIOUS WEB DESIGNER SHOULD HAVE

INTRODUCTION

Display your images with this slideshow applet. The applet rolls away an image on top of another using a 3D shading effect. After a pause, the procedure is repeated. The applet has the following features:

• Images support descriptions and URLs. Multiple target frames are supported.
• Images are loaded when needed and automatically resized to fit in the applet window.
• You can specify the description text and background color.
• The roll size can be specified.
• Confirmed compatibility with Netscape versions 3.01 to 4.5 and Microsoft Internet Explorer versions 3.0 to 4.1 for Windows 95/98/NT4. Also compatible with Netscape versions 3.0, 4.05 and Internet Explorer versions 3.01 and 4.5 for Macintosh.

Before using this applet you must read the license agreement.

APPLET INFORMATION

DEPENDENT FILES

The following file must be included with the applet in order for it to function properly:

mmrolloffimage.class

GENERAL PARAMETERS

This applet is configurable with normal HTML applet parameters. The first thing that must be done is to configure the applet main tags:

<APPLET CODE="mmrolloffimage.class" WIDTH=200 HEIGHT=200>
</APPLET>

As you can see, the size in the example is 200x200 pixels. You can change the dimensions to whatever size you wish. However, you take note that sometimes a big applet requires more processing power which may be hard for some computers. The following parameters may not be changed:

<PARAM name="mandomartis0" 
value="This is an applet from Anibal's Essential Applets package">
<PARAM name="mandomartis1" 
value="It was developed by Anibal Wainstein / Mandomartis">
<PARAM name="mandomartis2" 
value="Get it at http://www.mandomartis.com/essentialapplets/">

These are Mandomartis credits are are used to identify the applet. The following parameter controls the general frame delay in milliseconds, and thus the frames per second (FPS). The default value is 70:

<PARAM name="delay" value="70">

COPY PROTECTING THE APPLET, THE HOSTNAME AND FILENAME PARAMETERS

The applet is a commercial applet and must therefore be copy protected for your server, so that no one can take the applet and use it for his/hers homepage. There are two parameters that handles this, the encrypted "hostname" and "filename" parameters. What happens is that the applet reads the hidden host name and file name in these parameters and compares it to the server name and file name that it is imbedded in. If they do not match, then the applet will not work. Note that with "filename" we mean both the filename AND the path to the file. Let us take an example:

Let us assume that the URL where the applet will be located is:

http://www.myhostname.com/myapplet/help.html

The host name in this case happens to be "http://www.myhostname.com"
and the filename is "/myapplet/help.html".

The hostname and filename parameters does not have to be exact.
So the possible host names could be "www.myhostname.com", 
"myhostname" or "myhostname.com". While filename could be 
"myapplet", "myapplet/help.html", "help.html" or just "help". 
For the applet the hostname and filename parameters are search 
keywords that are use search in those two strings
 

Please note that in the example above we have not specified the "http://". You must not do that. You should know that the hostname and filename part of the url where the applet is inbedded in must be specified separately. Also the hostname must be more than 4 charaters long.

You can specify several hostnames and filenames if your homepage files can be reached from two or more different servers or from several mirror sites. Suppose that you have a company and you have your own hostname, e.g. "www.yourcompany.com". You have an Internet provider named "internetprovider" as well. Visitors can then access your file through your host "www.yourcompany.com/myfile.html" and through your Internet provider "www.internetprovider.com/yourcompany/myfile.html". The first hostname could be "www.yourcompany.com" and the second "www.internetprovider.com". The filenames could both be "myfile.html.".

As we said earlier the hostname and filename are encrypted. Therefore you must use the encoder applet for each applet and enter the hostname or filename there. You have two fields there where you can write each hostname and filename. The resulting HTML parameter content can then be pasted into the HTML page. The resulting HTML code could look like this:

<PARAM name="hostname0" value="~y31u:PR.FrazjkRsfPhh+k">
<PARAM name="hostname1" value="dl34jk-d~sa:fas">
<PARAM name="filename0" value="dy">
<PARAM name="filename1" value="sadf:ds/dsfa">

To run the encoder applet that was included in the package, you open the HTML file "encoder.html" in your favourite web browser.

The last thing you should know is that if you have put the applet on an URL called "http://www.yourhost.com/index.html" then you must specify a slash "/" as filename. Because you can reach this URL by writing "http://www.yourhost.com/" and "http://www.yourhost.com/index.html". By writing a slash "/" you cover both possibilities. Here are more examples of hostname and filename specifications:

Your URL:                  http://www.hellespoint.com/
Recommended hostname:      hellespoint
Recommended filename:      /

Your URL:                  http://www.larshomepage.com/products.html
Recommended hostname:      larshomepage
Recommended filename:      products.html

Your URL:                  http://henkesimage.sweden.se/list/
Recommended hostname:      henkesimage.sweden
Recommended filename:      list

Your URL:                  http://myhost.lnet.com/~john/home.html
Recommended hostname:      myhost.lnet.com
Recommended filename:      ~john/home.html

The applet will "see" what you see in the adress field on your browser when you enter your homepage. As long as you remember this you will be able to configure the applet without problems. Note also that you must have the exact number of hostnames and filenames for else the applet will not work (one filename for each hostname).

SETTING UP THE IMAGES WITH DESCRIPTIONS, URLS AND TARGET FRAMES

Write each image filename using the "image" parameter like this:

<PARAM name="image0" value="image0.jpg">
<PARAM name="image1" value="image1.gif">
<PARAM name="image2" value="image2.jpg">

Specify your first image in the parameter "image0", in "image1" you specify the second image and so on. Note that the only image formats supported are JPEG and GIF files. Do not use transparent GIF files in this applet. Also note that each image will be automatically resized to fit in the applet window.

The same system of adding images is applied for the descriptions which will appear at the bottom of the applet ("description"), the URLs ("url") and target frame name for each URL ("target") respectively:

<PARAM name="description0" value="This is image 0">
<PARAM name="description1" value="This is image 1">
<PARAM name="description2" value="This is image 2">
<PARAM name="url0" 
value="http://www.mandomartis.com/essentialapplets/">
<PARAM name="url1" value="http://www.mandomartis.com/">
<PARAM name="url2" value="http://www.mandomartis.com/">
<PARAM name="target0" value="_top">
<PARAM name="target1" value="_top">
<PARAM name="target2" value="_top">

Now the content of "description0" will be displayed when you move the mouse pointer across the applet area. If you click on the applet area then the applet will jump to the URL that you have specified for that message. Note the "http://" and the host on each URL. You MUST specify full URLs. Relative URLs will not work with this applet. If a target frame name has been specified then the URL will be invoked on that specific frame. The values "_top", "_self", "_left" and so on, are standard built-in HTML target frames.

SELECTING COLORS

The "decriptiontextcolor" and "descriptionbackgroundcolor" are the color that the description text and it's background color will have.

<PARAM name="descriptiontextcolor" value="00ff00">
<PARAM name="descriptionbackgroundcolor" value="000000">

OTHER PARAMETERS

The "sleeptime" parameter affects the pause before next image appears, you specify the value in milliseconds:

<PARAM name="sleeptime" value="2000">

Use the "step" parameter to increase the rolloff speed:

<PARAM name="step" value="3">

The "effectwidth" parameter sets the size of the "paper roll". This parameter must be kept small.

<PARAM name="effectwidth" value="30">

EXAMPLE OF A FULL CONFIGURATION

The following HTML text is an example of an applet configuration:

<APPLET CODE="mmrolloffimage.class" WIDTH=200 HEIGHT=200>
<PARAM name="mandomartis0" 
value="This is an applet from Anibal's Essential Applets package">
<PARAM name="mandomartis1" 
value="It was developed by Anibal Wainstein / Mandomartis">
<PARAM name="mandomartis2" 
value="Get it at http://www.mandomartis.com/essentialapplets/">
<PARAM name="hostname0" value="X/rujrX)-3HXc~i5l3Lcy6">
<PARAM name="filename0" value="t/">
<PARAM name="delay" value="70">
<PARAM name="sleeptime" value="2000">
<PARAM name="descriptiontextcolor" value="ffff00">
<PARAM name="descriptionbackgroundcolor" value="000000">
<PARAM name="step" value="4">
<PARAM name="effectwidth" value="30">
<PARAM name="image0" value="scenery0.jpg">
<PARAM name="image1" value="scenery1.jpg">
<PARAM name="image2" value="scenery2.jpg">
<PARAM name="image3" value="scenery3.jpg">
<PARAM name="image4" value="scenery4.jpg">
<PARAM name="description0" value="Pointing at image no 1">
<PARAM name="description1" value="Pointing at image no 2">
<PARAM name="description2" value="Pointing at image no 3">
<PARAM name="description3" value="Pointing at image no 4">
<PARAM name="description4" value="Pointing at image no 5">
<PARAM name="url0" 
value="http://www.mandomartis.com/essentialapplets/clickpage.html">
<PARAM name="url1" 
value="http://www.mandomartis.com/essentialapplets/clickpage.html">
<PARAM name="url2" 
value="http://www.mandomartis.com/essentialapplets/clickpage.html">
<PARAM name="url3" 
value="http://www.mandomartis.com/essentialapplets/clickpage.html">
<PARAM name="url4" 
value="http://www.mandomartis.com/essentialapplets/clickpage.html">
<PARAM name="target0" value="_top">
<PARAM name="target1" value="_top">
<PARAM name="target2" value="_top">
<PARAM name="target3" value="_top">
<PARAM name="target4" value="_top">
</APPLET>

© Copyright 2001-2005 Mandomartis Software Company