Creating WAP Services
by Luca Passani


Listing One
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" 
                             "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
 <template>
  <do type="accept" label="Help">
   <go href="index_help.wml"/> 
  </do>
 </template>
 <card id="logo" title="WAP Radio" ontimer="#frontpage">
  <timer value="30"/>
  <p>
   Welcome to
   <img src="pix/radio.wbmp" alt="WAP Radio"/>
  </p>
 </card>
 <card id="frontpage" title="WAP Radio">
  <p>
   <anchor>Pick up a song
    <go href="#picksong" />
   </anchor>
   <anchor>Today's programs
    <go href="programs.wml" />
   </anchor>
   <anchor>news
    <go href="news.wml" />
   </anchor>
  </p>  
 </card>
  <card id="picksong" title="Pick up a song">
  <do type="prev" label="Back">
   <prev/>
  </do>
    <p> Artist or song title: <input type="text" name="searchkey" value="" />
    <anchor title="search">Search
            <go href="songlist.php3" method="get">
         <postfield name="searchkey" value="$(searchkey)" />
      </go>
    </anchor>
    </p>
   </card>
</wml>


Listing Two
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
                     "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<template>
 <do type="prev" label="Back">
  <prev/>
 </do>
</template>
  <card id="index_hlp" title="help">
   <p>  
    This text is supposed to explain what happens in this deck. It should 
tell users that they can browse the news, see today's programs on the radio, 
and even pick up a song to be sent later on.
 <br />
Associating a  help deck to each deck that implements a certain
function is an excellent way to provide context-sensitive help.
 <br />
 Generally speaking having a context-sensitive help system is a good idea in 
the case of WAP services. Screens real estate is limited and the text used 
to guide users can be cryptic.
<br />
Don't forget a back button
   </p> 
  </card>
</wml>


Listing Three
<?php //header("content-type:application/xml"); 
  header("content-type:text/vnd.wap.wml"); 
  echo "<?xml version=\"1.0\" ?>\n";
  echo '<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" ';
  echo '"http://www.wapforum.org/DTD/wml_1.1.xml">'; 
?> 
<wml>
<template>
 <do type="prev" label="Back">
  <prev/>
 </do>
</template>
<?php
 //there are several things that can go wrong
 $ok = false;
 if ($searchkey && strlen($searchkey) > 2) { //good start. 
                                         // We have something to search for
    mysql_connect("localhost:3306", "root", "");
    $query = "SELECT * FROM songs " . 
             "WHERE title LIKE '%$searchkey%' OR artist LIKE '$searchkey%'";
    $result = mysql_db_query("wap", $query);
 
    if ($result && mysql_numrows($result) > 0) {
       $ok = true;
    }
 }
 if ($ok) {
    //if there are multiple hits, user should choose one
    if (mysql_numrows($result) > 1) {
?>
 <card id="pickup" title="Choose from hitlist">
  <do type="accept" label="Help">
   <go href="songlist_help.wml"/> 
  </do>
  <p>
Pick up song: 
<select name='song'>
<?php   
  while ($r = mysql_fetch_array($result)) {
    //echo("<option value='".$r["song_id"]."'>".$r["title"]." - 
                                              ".$r["artist"]."</option>\n");
    //display is too small. create entry for song and entry for artist
    echo("<option value='".$r["song_id"]."'>".$r["artist"]."</option>\n");
    echo("<option value='".$r["song_id"]."'>".$r["title"]."</option>\n");
  } ?>
</select>
<?
  } else { //only one hit, selected by default
     echo("<card id=\"pickup\" title=\"Choose from hitlist\">\n");
     $r = mysql_fetch_array($result);
     //one way to do it is with setvar (as follows)--but consider 
     //                                                   the side effects
     //echo("<onevent type='onenterforward'>\n");
     //echo("<refresh>\n");
     //echo("<setvar name='song' value='".$r["song_id"]."' />\n");
     //echo("</refresh>\n");
     //echo("</onevent>\n");
?>
 <do type="accept" label="Help">
   <go href="songlist_help.wml"/> 
  </do>
 <p>
   you chose: <br />
<?
   echo($r["artist"].":".$r["title"]."<br />\n"); 
  }
?>
your message:
<input type="text" name="message" />
<anchor title="next">Next
  <go href="confirm.php3" method="get">
<?
   //if there are multiple entries, use the one selected
   //by the user. Otherwise, use the only hit available
   if (mysql_numrows($result) > 1) { 
     echo("<postfield name=\"song\" value=\"$(song)\" />\n");
   } else {
     echo("<postfield name=\"song\" value=\"".$r["song_id"]."\" />\n");
   }
?>
   <postfield name="message" value="$(message)" />
 </go>
</anchor>
  </p>
 </card>
<?
} else { //something went wrong, try again
?>
 <card id="sorry" title="No song found">
  <do type="accept" label="Help">
   <go href="songlist_help.wml"/> 
  </do>
 <p>No match. Try with a different search key:
  <input type="text" name="searchkey" value="<?php echo($searchkey) ?>" />
    <anchor title="search">Search
            <go href="songlist.php3" method="get">
         <postfield name="searchkey" value="$(searchkey)" />
      </go>
    </anchor>
  </p>  
 </card>
<?php
 }
?>
</wml>

Listing Four
<?php //header("content-type:application/xml"); 
  header("content-type:text/vnd.wap.wml"); 
  echo "<?xml version=\"1.0\" ?>\n";
  echo '<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" ';
  echo '"http://www.wapforum.org/DTD/wml_1.1.xml">'; 
?>
<wml>
<template>
 <do type="prev" label="Back">
  <prev/>
 </do>
</template>
<?
  mysql_connect("localhost:3306", "root", "");
  $query = "SELECT * FROM songs " . 
             "WHERE song_id = $song";
  $result = mysql_db_query("wap", $query);

  //not much error handling for simplicity sake
  $r = mysql_fetch_array($result);
?>
  <card id="confirm" title="Thank you!">
   <p>  
 You picked:<br/> <?php echo($r["title"]); ?> by 
                                      <?php echo($r["artist"]); ?><br />
 Your message:<br />
 <?php echo($message); ?><br />
<?
  //let's insert the data in the playlist table
  $query = "INSERT INTO playlist VALUES (NULL,".$r["song_id"].",
                  \"".$r["title"]."\",\"".$r["artist"]."\",\"$message\")";
  //echo("<!-- $query -->"); 
  $result = mysql_db_query("wap", $query);
?>
 Thank you for listening to WAP Radio 105 FM.<br />
<a href="index.wml">Go to front page</a>
   </p> 
  </card>
</wml>






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